BCM Community

Yep, it looks like my 8Ds have bit the dust. I see new one cost about $250 each. I have some questions.

First off, on the Series 60 how much is the amperage draw during starting?

Next, is a pair of deep cycle batteries going to be adequate for starting?

Next, will the deep cycle batteries last longer?

Also who makes the best battery for the money in terms of battery life?

Any recommended vendors that might be close by? Like Tire Discounters for Interstate Batteries for example?

I see that Rural King has a CFT8D-3 battery for $144.99, would this battery be a good choice?

Jim

 Deep cycle batteries are not good for starting batteries,, and starting batteries are not good for house batteries that do better with deep cycle types..>>>Dan

@Jim
Hands down the battery I'm about to suggest to you is the best we have experienced in our 42 years of same bus ownership and many many 8D replacements. Would also like to say - at least in the WLA group, not all batteries are created equal not even if it is the same battery manufacturer sold under different retailers.
Any way we just replaced a pair of NAPA 8D Hybrid batteries. Hybrid batteries will take the abuse of starting and deep cycle discharges & charges. The last pair I got 7 years out of them and didn't start TLCing them until a couple years into their life cycle. With the state of the art four stage smart charging I'm shooting for 10 years on the current ones.
Engine start batteries are Napa 8D # 8276 X two with a 10% sale discount was $460 w/tx total

Our house bank batteries are Napa group 31 X five with a 10% sale discount were $760 w/tx total

Grand total $1220 which would have bought one lithium - we can't go there.

Our house bank & start batteries are totally compatible with each other and with the use of Blue Sea Marine RBSs can switch between or combine all for start or house bank (inverter).
That's my take & set up fwiw.

The start/deep cycle debate is valid at small capacities, do't get them mixed up.

However, a typical larger house bank of deep cycles will start the bus just fine, without any worry.

Be bold, just make a single bank, simplify your charging, and with a combination of smart equipment, and your own vigilance, just save the money and hassle of 2 different banks to take care of?

Dead battery is punishment for not managing correctly?

Happy coaching!
Buswarrior

In my former MC5, now sold, I replaced the start batteries with deep cycle ones, and combined them with the house bank, to form a single bank of 8 golf cart batteries. Works good. I always preheat the engine on a cold day, so it starts easy, and doesn't take much out of the batteries anyway. To support such a system, you need to keep the batteries up with solar panels and a good reliable generator if you are not plugged in to shore.

OK, I ordered the two NAPA batteries and will pick them up tomorrow. There was a 20% promo so that was about $200 ea. plus the core charge which I'll get back. Also had to buy the terminal converters of course. another 8 bucks, and then about $40 in tax (seems excessive somehow but we gotta pay that "protection" money, and I gotta say it's far better than having a local war). Pick-up tomorrow, 15 mile hike, could be worse.

Now I really should upgrade my maintenance. Two things come to mind. First at least some form of rudimentary charger to maintain them at the optimum voltage and not overcharge, and somewhere I saw a reference to an automatic electrolyte level device. Anybody familiar with that?

I know the charger is a hot topic. I have a bunch of chargers. An Everest & Jennings 24v but the only automatic function is a shutdown and then it doesn't reawaken on voltage drop so of limited help. A Ruski 24v that seemed to be doing well until it burned up and let the batteries discharge, Didn't really seem up to the job. Several 12v chargers of various capacities but all manual and one automated HF 12v starter/charger that should be fine for one battery but not both. It seems the simplest effective solution would be to buy a second HF unit, of course they are too large to locate on the bus easily. Not currently willing to spend more on the battery minders than I spent on the batteries so what suggestions? Thx

Jim

I would have 3-size 31 batteries to start (depending on what voltage you have-if 24v then 4-31's) then for house batteries 2 or 3 8D AGM batteries. Good Luck, TomC

Most smart battery chargers aren't smart enough for a 8D (230 amp hours).

I really like the 'noco genius 10' -- If there is a better one, I haven't used it.
I got 2 of them & have to isolate each battery while using them.

They brought a couple of group 31 that were at 1.5V back to fully functional.

I also love the noco genius line of smart charger/maintainers.

Long, long life for the lawn mower batteries kept on them between uses.

The coach will get its own set for redundant use.

Happy coaching!
Buswarrior

I just looked at those, and the least expensive ones that charge 24v were over $500. Can't really justify that right now. The HF unit to match the one I already have would be $150 so it's going to cost something regardless of how I handle it. What do you guys think of this one?

https://www.ebay.com/itm/303477514107?chn=ps&mkevt=1&mkcid=28 

Jim

All these chargers put out great numbers for charging, but once checking details, down to 40 to 60 amps charge.

Quote from: Jim Blackwood on September 05, 2021, 07:11:32 PM
I just looked at those, and the least expensive ones that charge 24v were over $500.

Jim -

My coach has four Group 31 start batteries, and four 8D deep-cycle house batteries.

The house batteries are kept up using the inverters or genset, depending on whether or not I'm plugged in to shore power.

When parked for any length of time, I have two Noco Genius 2x2 chargers that I'm extremely pleased with. For best results, since my start batteries are wired for 24vdc, I completely disconnect all four batteries, then hook up the charging leads individually and just let them do their thing. No complaints in two years of operation. Here's a link to their website: https://no.co/genius2x2

Now, if I was to do it again, I would pick up one of the new Noco Genius 2x4 units, a single charger than can handle four batteries at once, that's also reasonably priced at just under $200. https://no.co/genius2x4

I realize that both of these models are only 2 amps per leg, but since their primary usage in my case is to maintain the batteries over a month or more while stationary, they're perfect for my application. I also realize that for some folk, having to disconnect all four batteries when parked, then having to reconnect them again when getting ready to roll, will be considered a PITA, but I just look at that as a minor inconvenience compared to the cost of replacing the start batteries more frequently, plus being able to have them fully charged so as to prevent a "no start" dead battery situation for me is not an inconvenience. 

(BTW, my start batteries are NAPA Commercials, #7234.)

FWIW & HTH. . . ;)

I really appreciate the advice given thus far. Also, I have tried to keep up with the threads that talked about inverters and it seems that word is used to encompass much more than converting 24vdc to 115vac. But since I am not running solar nor have any immediate plans to do so it seems they might not be suitable for my needs. (I have a surplus of 900w inverters since 9 came with the bus. They will not charge the batteries, but they will power pretty much all of my 115v needs otherwise.)

At present I have no house batteries and this will not change until the RV is ready to roll. No point in investing in batteries and tires if they are just going to sit there.

I'd prefer to avoid decoupling the batteries aside from the disconnect switch which is what makes the Stark booster/charger above attractive since it will charge a 24v bank. Agreed it is unlikely to meet the claimed 300A starting current. Indeed the rated charging current at 24v is 35A. But that should be enough I would think. What I like about it is the ability to "maintain batteries indefinitely" controlled by the microprocessor, so presumably unlike the Everett & Jennings after the batteries are charged it won't just shut down and turn off. I think this "feature" was responsible for the early demise of my Exide batteries after just 5 years of light service. And I'm pretty sure I can find enough space for the Stark to make it a permanent part of the rig. If it works as it should I should never have any need to use it's max charging capacity.

My system does seem to have a parasitic loss on the 12v side and I haven't begun to rewire the power system yet. When I do I will include a disconnect for the Vanner center-tap at the very least, but I don't know if that will be enough. I had hoped to put off the rewiring and searching out the parasitic losses until later but it seems I'm paying for that procrastination.

Jim

Not sure why batteries are being disconnected to put 12 volt chargers on?

Just hook 'em up and job is done?

I wouldn't buy a 24 volt charger for maintenance purposes, 2 reasons: won't correct imbalance, smart parts can't massage a problem cell as easily, or at all,  and 24 volts is useless for anything other than the bus.

These chargers move around at my place, cars, mowers, generators, all need some time on these good chargers, and i am not buying one for each...

Happy coaching!
Buswarrior

Ditto plus battery disconnects are convenient...

Quote from: buswarrior on September 06, 2021, 08:00:06 AM
Not sure why batteries are being disconnected to put 12 volt chargers on?

Just hook 'em up and job is done?

I wouldn't buy a 24 volt charger for maintenance purposes, 2 reasons: won't correct imbalance, smart parts can't massage a problem cell as easily, or at all,  and 24 volts is useless for anything other than the bus.

These chargers move around at my place, cars, mowers, generators, all need some time on these good chargers, and i am not buying one for each...

Happy coaching!
Buswarrior

I use Pulse Chargers on my batteries. You can also buy a unit that will maintain each battery a given amount of time, then switch to the next.

Sounds expensive. Well, the Stark also does 12v/34A if I needed to use it that way but with the other chargers I have it's pretty pointless to do it I think since I can just use one of them. Maybe for reconditioning but if I keep these two 8Ds topped up shouldn't it be a few years before I have those problems? That's the issue for me. I'm lousy about battery maintenance and I realize it. Got a lot of batteries around the place and they all get about the same attention, which is basically to replace them when they go bad. I know, that's horrible. If I was retired maybe I'd have the time to do it right... no, wait. I AM retired. Oh, it's hopeless. A couple bills is all I can swing and you don't get much for that these days. I'm feeling poorly after buying all that stuff for the bus. I don't understand how these fancy chargers are supposed to work so it's hard to justify the extra money.

Disconnects are a good idea but the only easy to use,  reliable yet reasonably inexpensive ones I am familiar with are marine battery switches. Which are pretty good but still cost money both to buy and to install, and then still don't solve the charger issue. I like the fact that you can open a small door and throw the main disconnect. It'd be nice if that was all you had to do.

Jim

Andy says the military are using a matt of solar cells on the roof of their vehicles because they spend so much time in storage. Seems like a reasonable idea, don't need enough capacity to recharge or carry loads, but enough to keep the batteries from running down. What would be suitable for a bus?

Jim

We have a measly 500W split system. 400W on house bank & 100W on the starts. It's great - lot less need to charge with the pole nor the genny.

Quote from: Jim Blackwood on September 06, 2021, 11:38:01 AM
Andy says the military are using a matt of solar cells on the roof of their vehicles because they spend so much time in storage. Seems like a reasonable idea, don't need enough capacity to recharge or carry loads, but enough to keep the batteries from running down. What would be suitable for a bus?

Jim

My knowledge of chargers is quite limited, but as I understand  -
- the lowest voltage cell tells the charger when to start.
- the highest tells it when to stop
- disconnecting batteries reduces the number of cells
- 'smart' chargers are better at getting all cells up to the same level of charge
- 'smart' chargers WILL NOT work as well if there are ANY loads attached to the battery (disconnecting solves this)
- 'smart' chargers have limits as to how big of a battery they can charge effectively

I was having sporadic starting issues which lead to a dead starter -- so-- I got some Cole Hersee switches off ebay (- 1/2" stud rated at 300A continuous/2000 start ), a hydraulic crimper, wire & lugs to make my own cables. Was not cheap, but I haven't had any issues since. (now it is easy to make custom cables anytime I need)

My experience is it usually costs less in the long run to do it right the first time  ;)
The only thing cheap about these big rigs seems to be the owner  :P

A wise man once told me " If you are going to eat like an elephant, expect to poop like one too"   :o

Seems reasonable but... the charger can only see the total of all cells in the battery. Because the cells are in series there is simply no way to differentiate one from another. Of course low voltage can indicate a bad cell but no way to say which one. I think about the most you can hope for is that by splitting the bank you can at least tell which battery has a bad cell and then the hydrometer can tell the rest.

But as to the finances of the situation. I'm on a fixed income with a nest egg. When Edith retires I may be able to look to her for additional funds if she deems it worthy. No guarantees but I am ever hopeful. And there is at least the possibility of a modest inheritance at some point. So I need to be circumspect about my expenses. House batteries will be one, tires will be another, and those are pretty much unavoidable. In the meantime there is much to do. AC compressors will approach 2 grand for instance. There are some things I can do to keep costs down and some I cannot and quite a bit of it is discretionary. The battery charger falls into that category.

On one hand, I can disconnect the batteries at the terminals and use my 6/12v 200A processor controlled starter charger by moving it from battery to battery periodically, checking electrolyte, and only attaching the leads when needed. Cost: absolutely nothing but labor even should I need a bit of battery acid which I have on hand in more than adequate quantity, for anodizing. But the labor is more than I am happy with.

At the other end of the spectrum I can pay a couple grand for a high powered inverter, buy an expensive hydraulic cable crimper and cables, and fit each battery with it's very own disconnect, even use contactors and remote controls if I like. And maybe plate the top of the bus with solar cells.

I consider both ends of the spectrum to be undesirable for a number of reasons mostly having to do with convenience on one hand and cost on the other. What I'm looking for here is a modest means of removing the worst of the inconvenience while enhancing the reliability overall. As mentioned I'm not historically very good at battery maintenance, and I want to give my brand new start batteries the best chance for a long life. To me that means an onboard charger of some sort that will hold up for the long haul, simply for maintaining the batteries. I thank you all for all the valuable input.

It's not decision time yet. NAPA tells me the batteries will be there tomorrow. So there is still time to think about this and solution #1 will suffice short term. But I have no intention of leaving my best starter/charger sitting out in the rain next to the battery compartment any longer than I have to.

I also noticed that nobody had anything to say good or bad about the automatic watering system to keep the electrolyte level optimized. Has nobody else heard of this?

Jim

I have four group 31 AGM batteries to start my bus.  I could probably get by with two batteries, but I didn't want to figure out how to rewire things at the last minute.

I use a Battery Tender 24 volt charger to keep the start battery bank charged when the bus is not in use.  The Battery Tender can't be doing too bad as my starting batteries were purchased in December 2010.

Thanks. Apparently there are several.
Currently I am using this as a baseline for comparison:

https://www.ebay.com/itm/303477514107?chn=ps&mkevt=1&mkcid=28

Microprocessor based, 12v/24v and 35A continuous charge rating. Plus the large cabinet would seem to indicate good power dissipation. There should be a decent possibility of removing it from the case for a custom install. I've been inside an old manual one changing the rectifier over to the diode pack out of a big GM alternator. 

More than I'd like to pay but it seems to be good value for the money. I'm used to this type of charger, having one in 6/12v and the old manual one that I use when brute force is required. Neither really suitable for the bus though.

Jim

I don't want automatic watering, because i want to know what's going on.

Water use by batteries is a delicate balance between using them, and abusing them. Too much water consumption, and the batteries are being beaten by the charging equipment, or a cell is on the way...

Automatic filling leaves you ignorant and blind as to what condition your batteries are in, in an individual manner.

Happy coaching!
Buswarrior

Quote from: buswarrior on September 07, 2021, 11:35:42 AM
I don't want automatic watering, because i want to know what's going on.

Water use by batteries is a delicate balance between using them, and abusing them. Too much water consumption, and the batteries are being beaten by the charging equipment, or a cell is on the way...

Automatic filling leaves you ignorant and blind as to what condition your batteries are in, in an individual manner.

Happy coaching!
Buswarrior

The flip side is that for a battery bank which is difficult to access a watering system makes it possible (easy) to stay on top of things and not neglect adding water because it takes too long or is too difficult.

In an ideal world, your plan works great. Many of us have battery compartments which are made up of a few compromises.

Jim if you are going from post to stud cables invest in military grade adapters saves you a lot of grief later,I never knew why all military batteries are post then to stud cables but there has to be reason I guess 

I use an IOTA charger in parallel with my inverter, they are a decent price for a large amperage charge, and they have 24V options as well as the ability to buy modules to intelligently charge different types of batteries (I have a large AGM bank).

Having said all that, I'm going to trash my whole battery system and switch to lithium - I've had enough with silly lead acid and AGM batteries and their inability to discharge without getting damaged.  So I'll have an IOTA 24V charger and a Xantrex SW4024 up on ebay in the not too distant future.  :)

QuoteBe bold, just make a single bank, simplify your charging, and with a combination of smart equipment, and your own vigilance, just save the money and hassle of 2 different banks to take care of?

That is what I will likely do when the current pair of group 31 start batteries are done and dead. The main house lithium bank has plenty to start the bus and is constantly topped each morning then charged as needed during the day.


One concern unresolved is using the house bank while the bus is running. It is no big deal to get the house to start the bus but not sure I like having the house and bus connected while running. Not worried about the drain but just the idea of connecting them together is a bit worrisome.


There might be a path to downsize or ditch the alternator if using the house bank only as it is charged via solar or generator if necessary.

Quote from: windtrader on September 07, 2021, 10:47:47 PM
That is what I will likely do when the current pair of group 31 start batteries are done and dead. The main house lithium bank has plenty to start the bus and is constantly topped each morning then charged as needed during the day.


One concern unresolved is using the house bank while the bus is running. It is no big deal to get the house to start the bus but not sure I like having the house and bus connected while running. Not worried about the drain but just the idea of connecting them together is a bit worrisome.


There might be a path to downsize or ditch the alternator if using the house bank only as it is charged via solar or generator if necessary.

A safe way to do this is with a battery-to-battery charger. Sterling makes some nice ones which are true multi-stage smart chargers and which have settings for lithium. I'd think having a battery on the bus side to help smooth out the power would be helpful, even if it's just a single battery.

It would be nice if there was an engine mounted alternator which was setup to safety and properly charge lithium battery banks like you'd have, but I don't think I've seen one yet. With something like this it would be much easier to have a single lithium bank.

Some people spend a ton of money on a battery bank ? why,I stopped in Fallon Nv to help a guy in a GM 4104 that had just spent 12 grand on Battle Born Lifepo batteries. The bus was worth about 5K tops probably less with a blown 6-71.I cannot see people paying 10 bucks a amp hour for batteries plus the solar system

There are alternator regulators designed for lithium batteries like the Wakespeed WS500.

I don't know what I will do once my batteries need to be replaced.  I am almost at the point where it might make sense to just run the generator 24x7 for power.  The fuel costs would likely be less than batteries every six years or so.

Quote from: belfert on September 08, 2021, 06:50:01 AM
There are alternator regulators designed for lithium batteries like the Wakespeed WS500.

I don't know what I will do once my batteries need to be replaced.  I am almost at the point where it might make sense to just run the generator 24x7 for power.  The fuel costs would likely be less than batteries every six years or so.

1/2 to 3/4 gals per hour will add up in hurry though with my 12.5 and Aqua Hot I sure notice the fuel use and cost

Ditto
I just replaced five group 31s (house bank) & two 8Ds (start) all WLA for about the cost of one lithium. Just too many places to spend $$$ these days... Besides I'm old school...

Quote from: luvrbus on September 08, 2021, 04:34:36 AM
Some people spend a ton of money on a battery bank ? why,I stopped in Fallon Nv to help a guy in a GM 4104 that had just spent 12 grand on Battle Born Lifepo batteries. The bus was worth about 5K tops probably less with a blown 6-71.I cannot see people paying 10 bucks a amp hour for batteries plus the solar system

I figure something like 100 gallons of diesel for my big trip every year to run the generator 24x7.  That is the same or less than the cost of just one AGM battery for my house bank.  I still have batteries that work for the moment so that is a decision to make in the future.

Going the other way on the posts. Battery has studs, cable has clamps. So I ordered the screw-on posts. Order was delayed until tomorrow maybe.

All good info but guys let me re-emphasize again the budget concerns if you don't mind. I've found what looks to be a reasonably good $200 charging solution that is essentially maintenance free. Basically, wire it into the bus and forget it maybe? (Probably won't work that way because it has a power-up sequence requiring manual input but still, 24v/35A at that price and microprocessor monitoring?) If anyone knows of a better bang for the buck I'd love to see it. At present anything over $200 is overbudget. When I get the house batteries I'll look at charging solutions for those.

Watering: Doesn't look like that is in my immediate future either as they seem to be kinda expensive for bits of tubing and zip ties. I guess the caps are special though.

Jim

QuoteIt would be nice if there was an engine mounted alternator which was setup to safety and properly charge lithium battery banks like you'd have, but I don't think I've seen one yet. With something like this it would be much easier to have a single lithium bank.

The PV array should always keep the bank charged, except where there may be days of dreary weather. In those instances, the genny can charge the battery up in a few hours.


Have no idea how much energy the bus uses to keep running once started. Headlights, wipers run on air i think, aux radiator fans, running lights, not much. Convert the lights to LED and not alot needed. Main concern is protecting the main lithium bank from everything bad possible that the bus can do to the battery. A huge diode (current direct only) from battery to bus would protect any surge back to battery but without an alternator not sure what could over load the battery.

Quote from: windtrader on September 08, 2021, 02:28:48 PM
The PV array should always keep the bank charged, except where there may be days of dreary weather. In those instances, the genny can charge the battery up in a few hours.


Have no idea how much energy the bus uses to keep running once started. Headlights, wipers run on air i think, aux radiator fans, running lights, not much. Convert the lights to LED and not alot needed. Main concern is protecting the main lithium bank from everything bad possible that the bus can do to the battery. A huge diode (current direct only) from battery to bus would protect any surge back to battery but without an alternator not sure what could over load the battery.

I wonder how long it will be before some bus guy figures out how to charge his batteries at the charging stations NV is installing at all their rest areas in the middle of nowhere. I was surprised to see those at a rest areas ,then in NV sometimes it is 200 miles between towns.A trucker told me the one in area 51 was for our outer space visitors just a rumor he heard   

Could stick a wind turbine on top of it I suppose. It'd be great on the highway and as long as you parked in windy locations, no worries. Right?

I think one of those barrel shaped ones might do the trick, mounted on a center pivot so it could turn to face the wind. Could be as wide as the bus and surely a couple feet in diameter.

Jim

Quote from: Jim Blackwood on September 08, 2021, 08:50:26 PM
Could stick a wind turbine on top of it I suppose. It'd be great on the highway and as long as you parked in windy locations, no worries. Right?

I think one of those barrel shaped ones might do the trick, mounted on a center pivot so it could turn to face the wind. Could be as wide as the bus and surely a couple feet in diameter.

Jim

People in Quartzsite have those and if you are close it is impossible for me to sleep if the wind starts blowing it sounds like a bunch of helicopters flying over you at 2 am 

Interesting. I bet someone savvy with airfoil design could make up one with quiet blades. Maybe give them a twist, and use an odd number of blades irregularly spaced, then use a full 2 sided airfoil design and make sure it maintains laminar flow. Things like that

Jim

Quote from: Jim Blackwood on September 09, 2021, 11:32:47 AM
Interesting. I bet someone savvy with airfoil design could make up one with quiet blades.
Jim

They have been trying for decades, and haven't got there yet.

Deploy one of those weedwhackers, and you'll soon discover it has suffered a mysterious blade breaking "bird strike".

Even polite company will go rogue on that nonsense...

Stick to silent solar and hospital grade mufflers on the noisemaker.

happy coaching!
buswarrior

If you were purchasing lead acid house batteries, what amp hour makes sense?

Is one 200 amp hour better than 2 100 amp hour?

I'm leaning towards solar more and more. I will have a 10kw genny as well.

Quote from: epretot on October 13, 2021, 05:41:14 PM
If you were purchasing lead acid house batteries, what amp hour makes sense?

Is one 200 amp hour better than 2 100 amp hour?

I'm leaning towards solar more and more. I will have a 10kw genny as well.

An amp hour is an amp hour.

The number of packages doesn't change the calculations.

Lead acid, you design to not use more than half of them before re-charge.

Common 6 volt golf cart batteries, from a high volume dealer, continue to win the cost battle, somewhere ~220 aH each, depending on brand.

happy coaching!
buswarrior

What about space saving? Does a higher amp hour make sense for that.

Given I'm starting from scratch...

There's no magic bullet.

You need lead to make amp hours. The more you want, the more you need.

Cruise a few battery sites, do some back of napkin math, be sure you are getting your math into similar values, build up to your target voltage for each example and cost your price per amp hour. You'll also find 8 volt batteries, as well as 6 and 12.

Beware that many 12 volt batteries are NOT the proper deep cycle batteries a busnut needs. If it says marine or RV, be very very suspicious...

For the install, get them stacked, in a pull out rack, made by you for the purpose. Too many people waste a ton of floor space, laying them all out.

Size the rack to house the taller Trojans, or L16 battery cases, if you ever feel inspired to go there in the future, and you need total access to the tops, to inspect and top-off water levels. The easier it is to inspect, the more likely it will get done...

The Lithiums are all the rage, but require more than a decades' worth of battery money to get going. Totally unnecessary expense in a vacation coach, and many full timers don't need them either.

Again, apples to oranges, you need their whole cost, lithium cells AND the BMS, if it isn't included, in cost calculation comparisons.

happy coaching!
buswarrior

Thanks. I have had a few people suggest the 6 volt. I'm leaning toward 8 - 6 volt lead acid.

Lithium is just crazy expensive as you know. I assumed electric would be the single biggest expense. Looks like I was right.

https://www.youtube.com/c/WillProwse/videos

https://www.youtube.com/watch?v=3U4ZfQ_IToI

https://www.youtube.com/watch?v=Rp8Hspi4BC4

https://www.youtube.com/watch?v=WVxvBkeY0UY

https://www.youtube.com/watch?v=iy3hga_P5YY <- Best RV battery testing I've seen.

At 18:37 in the video, the cheapest lifecycle battery cost is lithium at 9 cents/KWh stored, versus 19 cents for flooded lead acid.  His lithium batteries were Battleborns, which are crazy expensive.   

The best value in batteries, by far,  is used Tesla battery packs. $1000 for 5.2 KWh usable.   

Scott Crosby has 12 of those Battle Born batteries and enough solar wattage to run a mini split AC & plenty for other stuff in his Silversides completely off grid.
We're of the dinosaur type and stay with flooded lead acid - pinching nickels as 5 group 31 FLA house bank cost half of one of those Battle Born.

Probably already chimed in here but lithium is far superior in nearly all performance aspects: better capacity to weight, better charge and discharge rate, better durability, better reliability. Cost at retail is higher than LA. DIY 90% less than retail. You need to do some learning but busnuts are generally a DIY crowd so at least check it out and don't let the neigh sayers close the door to a far superior power storage system.

Quote from: dtcerrato on October 13, 2021, 07:26:08 PM
We're of the dinosaur type and stay with flooded lead acid - pinching nickels as 5 group 31 FLA house bank cost half of one of those Battle Born.

My RV presently has a battery box that holds 6 GC batteries.   I'll be replacing them with lithium.

If you watch the last video, even the stupidly expensive Battle Borns are much much cheaper than lead acid in the long run.  Lead acids have very poor performance compared to what they are advertised as. 

FWIW, the cheapest battery is no battery, ie reduce the electrical load.  What do you need to run in your bus such that you need a big battery ?

I converted all the light fixtures to LED except for 2.  I've given up trying to run AC on lead acids.  It is a hopeless goal due to the Peukert effect.  The fridge will run on propane.   The microwave gets run once in a while, but only for a minute or two.  Rarely longer.   Our cook top is propane.  The water pump hardly uses any power.

We have 600W of solar.   I suspect a Tesla battery module would last a long, long time in our trailer as it sits.

I'm on the Starlink waiting list.   Apparently they draw about 100W or 2.4KWh/day.  That is quite a lot when boondocking, but maybe it wouldn't been to be powered 24 hours ? 

There is a big push to residential AC fridges in RVs these days.  A 10 cu ft fridge uses about 300 KWh/year, which is 1 KWh per day, including auto defrost.   I wonder if that can be turned off ?     

Starlink @ 100w/hr is likely the running draw. I'd be very surprised if the standby draw is more than 5w.


1kW a day for a refrigerator is trivial for a decently sized lithium battery bank. One other benefit many overlook beyond the hard comparisons is the increased usability and comfort by having 120v always on. Once we agree we are not of the roughing it crowd, it sure is be "at home" with all the modern electrical conveniences at the flip of a switch or the twist of a knob. Pole huggers won't notice but the enhanced luxury to the off grid boondocking experience is truly transformative in a positive way.

Nope, Starlink draws about 100 watts, all the time.  The current version anyway.

https://www.loveyourrv.com/starlink-satellite-dish-internet-first-look-setup-test-on-the-rv/

Furthermore, the dish itself has a built in heater.   In the case of snow or frost, the heater is turned on to remove the build up.  This draws more power.

Quote from: windtrader on October 13, 2021, 08:52:38 PM
1kW a day for a refrigerator is trivial for a decently sized lithium battery bank.

Sure, but everything has a cost.  Right now Battleborns are $800 for a 100ah 12V battery.   At 80% DOC, you'll get 1KWh of storage per battery.

I'm convinced lithium is better. However. Budget is a consideration.
I will have a generator as well

Without getting into all the details here, I want to be able to go anywhere anytime and have power.

We will have a residential ac fridge, minisplit, lighting, outlets, exhaust fans, etc. I would love to have a dehumidifier.

propane stove and water heater.

We have no use for a microwave. However, we use the instant pot a lot.

As I said before, starting from scratch, so...

Quote from: someguy on October 13, 2021, 08:40:39 PM
There is a big push to residential AC fridges in RVs these days.  A 10 cu ft fridge uses about 300 KWh/year, which is 1 KWh per day, including auto defrost.   I wonder if that can be turned off ?   

Depending on the refrigerator controls, the auto-defrost can be interrupted. Seek out the operating logic, and choose the place to interfere. I would install a switch, rather than just disabling it, so you can engage the defrost on your own terms. This will help get your ingenuity running: https://en.wikipedia.org/wiki/Auto-defrost

The other monster power hog in some residential refrigerators is the HEATER around the door to prevent condensation. The early adopters were quick to get that wire disconnected.

The refrigerator schematic is mission critical to making good moves for both.

happy coaching!
buswarrior

Times have changed in Rving back in the day you had 1 or 2 batteries for the house with 12v lights or propane lights no inverters  and times were good now people have batterie banks worth more than the rv. I have one of the electrical hogs and can afford the Lithium batteries but my AGM batteries do the job lol so did the golf cart batteries in my other RV's. So called boondocking has changed too now people want to set and watch satellite TV with their AC running in the middle of no where, the world just keeps spinning :'(

Quote from: buswarrior on October 13, 2021, 06:21:04 PM
There's no magic bullet.

You need lead to make amp hours. The more you want, the more you need.

Cruise a few battery sites, do some back of napkin math, be sure you are getting your math into similar values, build up to your target voltage for each example and cost your price per amp hour. You'll also find 8 volt batteries, as well as 6 and 12.

Beware that many 12 volt batteries are NOT the proper deep cycle batteries a busnut needs. If it says marine or RV, be very very suspicious...

For the install, get them stacked, in a pull out rack, made by you for the purpose. Too many people waste a ton of floor space, laying them all out.

Size the rack to house the taller Trojans, or L16 battery cases, if you ever feel inspired to go there in the future, and you need total access to the tops, to inspect and top-off water levels. The easier it is to inspect, the more likely it will get done...

The Lithiums are all the rage, but require more than a decades' worth of battery money to get going. Totally unnecessary expense in a vacation coach, and many full timers don't need them either.

Again, apples to oranges, you need their whole cost, lithium cells AND the BMS, if it isn't included, in cost calculation comparisons.

happy coaching!
buswarrior

x2   

I got 10 years out of the 1st set (6 x 6v GC bateries ) and the ones I have now are on year 6

way less cost but yes you will need to add water sometimes

dave

I have 4-4d deep cycle batteries. Interstates. Adding water tends to be a pita but that config is what was there when purchased coach. May consider an automatic waterer for it. Won't  go to the newest greatest because to many changes in the battery engineering and prices keep dropping per kw. Then a new type comes out, etc. etc. Plus the specific charging requirements. Don't  boondock enough to justify solar and expensive systems. Maybe in future, but probably not though.

Quote from: sledhead on October 14, 2021, 04:40:46 AM
I got 10 years out of the 1st set (6 x 6v GC bateries ) and the ones I have now are on year 6 way less cost but yes you will need to add water sometimes

Golf cart batteries are rated for 750 cycles.   https://www.golfspan.com/golf-carts/best-golf-cart-batteries  And as Morton's video shows, they degrade fast.  A single 6V battery will deliver about 450 watt hours per cycle.   750 cycles x 450 wh per cycle = 337.5 KWh of storage per lifetime.   They cost $100.  $100/337.5 KWh = 29.6 cents per KWh stored.

Battleborns are 100ah @12V, rated for 3-5,000 cycles.  They cost $800.  They will deliver a full 1 KWh at 80% depth of charge.   3,000 cycles x 1KWh = 3000 KWh of storage per lifetime.   $800/3000 KWh = 26 cents per KWh stored.

Tesla battery packs are 5.2KWh usable, will last for 2-3000 cycles.  Sell for $900-$1000, plus a BMS.  2,000 cycles x 5.2 KWh = 10,400 KWh of storage per lifetime.  $1000/10,400 KWh = 9.6 cents per KWh.

Your 6 GC batteries will cost $600.   A used Telsa pack will cost $1000, plus another $1-200 for a BMS controller.   So it is $1200 versus $600 for no watering, twice the capacity, way better load performance, and 3-4x the life. 

This dude is saying 500 cycles for a Trojan and only 300 cycles for a Costco battery.
https://www.youtube.com/watch?v=RO4N_V4Azvc

His energy stored math is wrong on two fronts.  1) Battery voltage does not stay at 6V as the battery is discharged, especially if discharging at a higher rate.   2) You don't get 232 ah at 80% depth of discharge.  You get 80% of 232 = 185Ah.  Big difference.

You'd need 5.2/450 = 11.5 golf cart batteries to get 5.2KWh of usable storage.  They'd last for 750 cycles, versus 2-3,000.


 

 I am still not sold on ION batteries after seeing a 2 mil Lady Liberty burn from a battery fire.I forgot how many amps the Telsa charging stations put out but it is a lot

Quote from: luvrbus on October 14, 2021, 10:17:15 AM
I am still not sold on ION batteries after seeing a 2 mil Lady Liberty burn from a battery fire.I forgot how many amps the Telsa charging stations put out but it is a lot

So ?  More buses burn from tire and brake fires and fuel leak than from batteries, by far.  Are you going to stop driving your coach too ?

Batteries (lead acid and lithium) burn from over charging.   Don't over charge or short out the battery and you'll be fine.  Tesla batteries have current links in them that blow if they are shorted out.

You aren't going to over current a Tesla battery pack unless you have a monster charger.  50A x 240VAC = 12KW, so no chance of that in a normal bus.  You could potentially over voltage them, but that is easily avoided with a proper charge controller.

Tesla battery packs have build in temperature sensors.  It is very easy to monitor what is going on within the pack.

Battleborn batteries have a BMS built into each battery.   There is zero chance of them starting on fire.

DO NOT USE CHEVY BOLT BATTERIES.

I was watching the military discharge the lithium batteries to dispose of some, they were treated like bombs,they had a special building you were not allowed to visit discharging the Lis02 batteries the young people were wearing Haz/Mat suits and masks.The military's has a lot of different compounds they use in Lithium batteries all deadly     

Someguy, that "presenter" and all the linked videos, is/are selling lithium batteries.

In the old world, it would be branded as "paid programming"

Making golf cart batteries look bad is in his best interest.

The average new busnut needs balanced reporting, and does not have the money to be paying for power, that far into the future, when they have many more important things to spend it on.

Happy coaching!
Buswarrior

Quote from: buswarrior on October 14, 2021, 01:42:37 PM
Someguy, that "presenter" and all the linked videos, is/are selling lithium batteries.

In the old world, it would be branded as "paid programming"

Making golf cart batteries look bad is in his best interest.

The average new busnut needs balanced reporting, and does not have the money to be paying for power, that far into the future, when they have many more important things to spend it on.

You can download Morton's data spreadsheets.  The techniques and equipment he uses are good quality and he uses the same equipment and techniques on the lithiums and lead acid batteries.

The last video I linked was selling Trojan lead acid golf cart batteries, not lithiums.

The capacity and cycle lifetime of Tesla batteries has been extensively tested buy several parties.

My first impression of these videos was favorable.

Then I realized everything is his favorite.

I think that might be a tell.

I'm certainly no wiser after reviving this thread.

Quote from: epretot on October 14, 2021, 05:06:27 PM
I'm certainly no wiser after reviving this thread.

Here you read all the comments (it gets deep) then do what suits the old wallet and yourself GC batteries will work they have for many years and don't break the bank ? how many batteries in a RV's are going to be cycled 5000 times in a RV .that rv will be long gone before they cycle that many times   

QuoteThe military's has a lot of different compounds they use in Lithium batteries all deadly     

Not sure exactly what you mean here but there are some chemistries such as the standard LiFePO4 that are totally unable to catch fire. There are plenty of videos showing how much extreme conditions they take with zero issues. There are other lithium chemistries that definitely are more sensitive and volatile but all are NOT DEADLY. Sorry Clifford, that is simply not true and a disservice to those already confused about looking into lithium batteries.

Quote from: windtrader on October 14, 2021, 05:42:21 PM
Not sure exactly what you mean here but there are some chemistries such as the standard LiFePO4 that are totally unable to catch fire. There are plenty of videos showing how much extreme conditions they take with zero issues. There are other lithium chemistries that definitely are more sensitive and volatile but all are NOT DEADLY. Sorry Clifford, that is simply not true and a disservice to those already confused about looking into lithium batteries.

Windy if you read I was speaking of the military lithium grade of battery they don't use a lifepo4 battery.The CO told me it cost almost the same amount they pay for the battery to dispose of them and I had interest because I help pay for it.I even got a tour of the Telsa battery plant in Sparks and they were working on a new battery to replace the older battery packs I think it was still lithium though     

Quote from: epretot on October 14, 2021, 05:04:46 PM
My first impression of these videos was favorable.

Then I realized everything is his favorite.

I think that might be a tell.

Did you look at the voltage and current versus time spreadsheets ?   They were generated with a datalogger.    Are you accusing him of  rigging test results ?

Besides, his results have been replicated elsewhere, particularly by Tesla cars and golf carts using FLA batteries.    The Peukert effect is real.

Quote from: luvrbus on October 14, 2021, 05:13:42 PM

Here you read all the comments (it gets deep) then do what suits the old wallet and yourself GC batteries will work they have for many years and don't break the bank ? how many batteries in a RV's are going to be cycled 5000 times in a RV .that rv will be long gone before they cycle that many times   

You might not cycle your RV batteries 5,000 times, but you will probably cycle them more than the 300 cycles that FLAs will get you.   And FLAs degrade sharply just sitting around.   

If you aren't going to use your batteries for a fridge, microwave or AC and you aren't going to cycle them deeply, or discharge them fast, FLAs will work.   But as soon as you start really using batteries for what they were meant for, all bets are off.

Here is what I'm saying.

I'm uncertain of what I should do.

As I see it, there are many here using all kinds of setups that are working.

And most of those people aren't too emotional about it.

Full disclosure: The purpose of my bus isn't simply for a home. While we will be full time, it will be used in a missionary capacity.

It is likely to be in locations where power is a premium. I'm thinking natural disasters or something like that.

So, I need to be able to go anywhere anytime.

I sold everything I own to execute this vision. I'm all in. Literally.

It's important that I get this side of things right.

Boiled down and without emotion, it's really a pretty simple decision:

Flooded cell or AGM will get you to your destination. The initial cost will be less but the lifespan will be shorter. You will also need to have more capacity going this route to reach the same goal since these batteries are best when not taken to less than 50% state-of-charge.

Lithium batteries will also get you there. The initial cost will be higher, but it will buy you less weight, more capacity (in the same physical space), less maintenance, quicker recharge, and longer life. But, you'll have to find a way to keep them warm if you every plan to recharge them in freezing conditions, and they will require a charger capable of outputting the correct voltage/amperage.

The big thing is how much cash you have for the initial setup. If you have enough for the lithium it will give you much more flexibility to be in conditions like you're describing.

You could always upgrade later to Lithium,they will come down in price as more manufactures  enter the market,LifeLine the premiere AGM battery Co has entered the market ,Johnson Controls, and Deka  are entering lol it want be long before you can buy those at Sams and Costco,My cost on a LifeLine LL12v100-27 is almost 1/2 the price of Battleborn. 27 is the group number the 100 is the amps  right now Lifeline only makes 2 the other is the LL-12V75-24. just wait it out they will get affordable if lithium is what you want       

In conjunction with Richard's lovely synopsis...

Busnuts make expensive mistakes on their initial ideas of what they need in the way of capacity, their consumption, their re-charge capabilities, choice of equipment...

And, have to start again, if they have any money left...

Few brag online about their mistakes, so the reporting is badly biased. In fact, electrical errors, being as expensive as they are, will figure prominently in project abandonment.

It is imparative for project survival, for the encouragement of the busnut community, that newbies are not stampeded into thinking they have to drop thousands of dollars on a battery set, when hundreds will do just fine to get them started, financially and culturally, to this whole busnut hobby thing.

This phenomonen of insecurity, ever more deeply embedded, where everyone has to join "my team" or else they are an idiot, isn't good for the uniqueness of bus conversion construction, never mind life in general...

Fair and balanced is what readers need.

Happy coaching!
Buswarrior

Quote from: someguy on October 15, 2021, 02:23:24 AM
You might not cycle your RV batteries 5,000 times, but you will probably cycle them more than the 300 cycles that FLAs will get you.   And FLAs degrade sharply just sitting around.   

If you aren't going to use your batteries for a fridge, microwave or AC and you aren't going to cycle them deeply, or discharge them fast, FLAs will work.   But as soon as you start really using batteries for what they were meant for, all bets are off.

Golf cart batteries are good for more than 300 cycles you even posted 750 cycles now it is 300  WTH

What also enters into this unbiased reporting is that once someone has spent thousands of dollars for the latest greatest thing, there is a natural tendency to claim that it is wonderful, whether it really is or not. We see this with batteries, power handling equipment, with air conditioning, maybe even with tires. It's hard to recognize when you might have made an expensive mistake and even harder to admit it. But that's the kind of honesty that would really help us all out.

Jim

Quote from: Jim Blackwood on October 15, 2021, 07:47:34 AM
What also enters into this unbiased reporting is that once someone has spent thousands of dollars for the latest greatest thing, there is a natural tendency to claim that it is wonderful, whether it really is or not. We see this with batteries, power handling equipment, with air conditioning, maybe even with tires. It's hard to recognize when you might have made an expensive mistake and even harder to admit it. But that's the kind of honesty that would really help us all out.

Jim

So true I recall buying my 1st big screen plasma tv a must have I paid over 12 grand now you buy a better and larger tv at Walmart for $700.00

Quote from: luvrbus on October 15, 2021, 07:25:31 AM

Golf cart batteries are good for more than 300 cycles you even posted 750 cycles now it is 300  WTH

I provided a link for a seller of GC batteries used in golf carts.  In that application they get about 300 cycles.  I believe that to be akin of inverter duty in an RV if you are running a fridge, microwave, AC, etc.

The 750 cycles is what the manufacturers claim and that is probably based on about 30% DOD.  It isn't based on 50% DOD.

I don't care what you believe or don't believe.   I'm just trying to share some information to counteract the FUD that goes on in these forums.

Quote from: Jim Blackwood on October 15, 2021, 07:47:34 AM
What also enters into this unbiased reporting is that once someone has spent thousands of dollars for the latest greatest thing, there is a natural tendency to claim that it is wonderful, whether it really is or not.

So show us a better source of FLA and lithium battery information then.

Quote from: someguy on October 15, 2021, 09:14:02 AM
I provided a link for a seller of GC batteries used in golf carts.  In that application they get about 300 cycles.  I believe that to be akin of inverter duty in an RV if you are running a fridge, microwave, AC, etc.

The 750 cycles is what the manufacturers claim and that is probably based on about 30% DOD.  It isn't based on 50% DOD.

I don't care what you believe or don't believe.   I'm just trying to share some information to counteract the FUD that goes on in these forums.

I will hand to you spending a lot of time on Google and Utube to try and prove your point

Quote from: someguy on October 15, 2021, 09:15:16 AM
So show us a better source of FLA and lithium battery information then.

What Me? I never claimed to be a battery expert. Best I could do is give you an opinion. Which you probably wouldn't like anyway.

But there's still and always will be a lot to be said for following the well traveled path. Yes, a side trail may be more profitable sometimes. And sometimes not. It usually depends on how observant you are. Some of us just really don't want to put out that kind of effort. In which case we'll just wait until the side trail is more well developed.

Jim

I have noticed on the newer rv's and bus conversions with the LifePo4 system is a total different system there is no boost switch from the LifePo4 to the starting system to tie the systems together and a decal telling you not to jump from the LifePo4.  ? for me is why not, is the voltage to high or what else is it going on there.I have been told by several battery out fits the LifePo4 cannot be used for starting batteries but was never told why and maybe someone here knows or can me give a educated guess

Everything you want or need to know about solar/lithium can be found on this forum. https://diysolarforum.com/
There are plenty of VERY knowlegible people who are VERY helpful. They even tolerate the odd dumb question from time to time.
Additionally they have a separate section for RVs.
The person who runs the forum,Will Prowse, has many(hundreds??) of utube videos where he tests different batteries, shows you how to build you own and tests other solar equipment. He also illustrates different setups depending on what you want to do.In addition he gives costs and links to purchase whats in his setups..He doesn't sell anything himself(other than his books)And, I find him
quite entertaining.

Quote from: Fred Mc on October 15, 2021, 01:12:56 PM
Additionally they have a separate section for RVs.
The person who runs the forum,Will Prowse, has many(hundreds??) of utube videos where he tests different batteries, shows you how to build you own and tests other solar equipment. He also illustrates different setups depending on what you want to do.In addition he gives costs and links to purchase whats in his setups..He doesn't sell anything himself(other than his books)

If you actually watched the links I provided, you'd see that I linked some of his videos.  And who else is active on that forum ?   Morton, who provided the test data, using... the same equipment that Will uses !  Oh, but Will has links on his YouTube channel for batteries that he endorses.  So his data must be biased. /s

SMH.

Quote from: luvrbus on October 15, 2021, 01:04:21 PM
I have been told by several battery out fits the LifePo4 cannot be used for starting batteries but was never told why and maybe someone here knows or can me give a educated guess

LifePO4 batteries are now used for starting most dirt bikes.  Most people replace the FLA stock batteries with LifePO4.

Bang for the buck starts here,,I RV extensively all over the country,, for 26 years and 2 motorhomes,,(one converted bus and one conventional DP RV.)..  The entire period of travel,,using an inverter and a residential fridg.,, and propane for heat plus about half my cooking I have averaged 6 years per battery bank of 4 GC2 6 volts..  The last bank I purchased was 9 months ago came to $500.00!! and had been used reliably for 6.5 years... NOT BAD FOR THE COST OF $83.0 PER YEAR.>>>Dan

Quote from: someguy on October 15, 2021, 02:09:58 PM
LifePO4 batteries are now used for starting most dirt bikes.  Most people replace the FLA stock batteries with LifePO4.

Dirt bikes a 10 amp battery will start,500 to 600 amps to start a bus is a lot of difference there.anyways it's a mute point I got my answer from a LifePo4 manufacture

Quote from: someguy on October 15, 2021, 02:07:33 PM
If you actually watched the links I provided, you'd see that I linked some of his videos.  And who else is active on that forum ?   Morton, who provided the test data, using... the same equipment that Will uses !  Oh, but Will has links on his YouTube channel for batteries that he endorses.  So his data must be biased. /s

SMH.

I like many are in the Kindergarten phase of understanding these systems.

I can watch all of the videos on the internet and it means nothing to me if I have no foundation.

Now, I need to get a better understanding.

Quote from: luvrbus on October 15, 2021, 02:51:21 PM

Dirt bikes a 10 amp battery will start,500 to 600 amps to start a bus is a lot of difference there.anyways it's a mute point I got my answer from a LifePo4 manufacture

Max current is relative to the size of the battery.    Dirt bike batteries are as small and light as possible.  20Ah IIRC.

As to why an RV with LiFePo4 batteries may label to not use as start batteries lies solely on two factors. Voltage needs to be the same. A 48v lithium battery pack starting a 24v or 12v start system is not recommended.


The only other factor is start amperage and that is directly related to battery capacity and C rating. Multiply the battery voltage by the nominal current (amp) rating of the battery and multiply by the discharge C rating (short duration, not continuous) and you get total watts available.


For example, my battery pack has 480 aH and 2C discharge for short periods is fine. This is 960 starting amps at 24v. The battery pack and cells need to be C rated as the connectors also need to be able to handle the current.

Quote from: windtrader on October 15, 2021, 04:48:33 PM
As to why an RV with LiFePo4 batteries may label to not use as start batteries lies solely on two factors. Voltage needs to be the same. A 48v lithium battery pack starting a 24v or 12v start system is not recommended.


The only other factor is start amperage and that is directly related to battery capacity and C rating. Multiply the battery voltage by the nominal current (amp) rating of the battery and multiply by the discharge C rating (short duration, not continuous) and you get total watts available.


For example, my battery pack has 480 aH and 2C discharge for short periods is fine. This is 960 starting amps at 24v. The battery pack and cells need to be C rated as the connectors also need to be able to handle the current.

Not quite the way James a engineer at Life Line explain it to me,jumping a 12 or 24 volt starting system with a 48v battery is funny, come on no one is that stupid I hope>I didn't ask about the jumping decal I read to mean jumping the house battery. I'll ask him about that.
You know the Delco 42 starter on your bus is a 900 amp 10 hp motor and they will draw those amps on a cold day I have seen higher, that is why lead batteries have cold cranking amps to turn that baby,The part I don't get is drawing a 100 amps from a 100 amp battery you only get maybe 30 seconds then drawing the same amps from a 100 amp battery would be like shorting one out I guess 

a major concern to me is, are these battery designs in the round screen color tv period or in the declining price vs screen size slide, seems like back when 8 track tapes were king. Good discussion though.
Also "theory" on what will be used on a planned system vs. actual money dropped for it needs to be considered.

Quote from: chessie4905 on October 16, 2021, 05:10:11 AM
a major concern to me is, are these battery designs in the round screen color tv period or in the declining price vs screen size slide, seems like back when 8 track tapes were king. Good discussion though.
Also "theory" on what will be used on a planned system vs. actual money dropped for it needs to be considered.

The part that throws me with LifePo4 is they last so long under normal use,then if you try  say you draw 500 amps from a 500 amp system for a starter they only last a few seconds as you well know sometimes a DD needs more than a few seconds .Then the high voltage a LifePo4 retains on a electronic engine it can cause damage to sensitive electronics I was told.I ordered 2 of the 100 amp LifeLines for Sonjas van I am going to give it try but I am keeping the 12v lead battery for starting.My price from LifeLine was no where near the $1000.00 for a battery there must be 1 hella of a markup on the LifePo4, lol freight prices are stupid high now on anything  80$ from CA to AZ is silly for 2 batteries     

Cliff, in your Prius, could be cheaper to drive there to pick up.lol

I don't  know how they are shipped, but UPS rates have gone up significantly here.

Well I know we never had any problems starting a 6v tractor with a 12v battery and there are a great number of 6v vehicles running 12v without ever changing the starter. The starter runs faster which makes the engine start easier... unless it has a magneto and spins too fast for the impulse mechanism. But the starters don't burn up and the batteries don't explode.

We also never had a problem running a 12v starter on 24v. That's pretty much the same situation, so why would you expect to have a problem running a 24v starter on 48v? I don't see any difference there except the batteries. Are you guys saying that the lithium batteries can't handle the high starting current?

Jim

You hit a 12 or 24 starter with 48 v they will burn the armature and sling the lead I have done before with a 200 amp DC Lincoln welding machine trying to start a engine when I blew the battery up doing the same thing that was long,long ago

Well that's just hilarious! You do realize that DC welder puts out something like 50 volts right? So at 200 amps you were putting some serious power into that battery, something like a full 10 Kw. I'd say it's no surprise it got hot.

And if you tried 48 volts on a 6v starter, well it'd run very fast for a very short time. But any decent starter will handle twice it's rated voltage for a reasonable time period and have a respectably long lifespan. It's done all the time. Like I said before. 12v on a 6v starter has been common since the 60's. 24v on a 12v starter isn't as common but is regularly done without issues. Why would 48v on a 24v starter be any different? The electrical loading is identical.

Jim

Quote from: Jim Blackwood on October 16, 2021, 02:14:31 PM
Well that's just hilarious! You do realize that DC welder puts out something like 50 volts right? So at 200 amps you were putting some serious power into that battery, something like a full 10 Kw. I'd say it's no surprise it got hot.

And if you tried 48 volts on a 6v starter, well it'd run very fast for a very short time. But any decent starter will handle twice it's rated voltage for a reasonable time period and have a respectably long lifespan. It's done all the time. Like I said before. 12v on a 6v starter has been common since the 60's. 24v on a 12v starter isn't as common but is regularly done without issues. Why would 48v on a 24v starter be any different? The electrical loading is identical.

Jim

I doubt I was getting 48 v since the Lincoln has adjustments for different voltage and amps and was no where close to max they have a DC plug for a grinder and other DC tools with 115 volt plug end and charging batteries with a DC welder is done all the time ,makes no difference starters built now blow a link if they sense voltage hi or lo hook 36 volts up to the starter on the series 60 of yours and give it a spin

Clifford,


Have your contact explain C ratings, particularly discharge rating. If a battery pack is rated at 100 amps, then that is 1C and virtually all batteries can draw 100amps continuously. The battery is capable of discharging at more than 1C but that depends on two things: how much current can it draw and for how long. Each battery has a curve where it shows how long it can draw at various currents. Some batteries packs such as those Lipo used in RC planes can discharge at 30C but for not very long. So a 100 amp battery can discharge at 3000 amps for some time. But you have to have the wiring and other components rated to pass that much current too. So the whole system has to be designed and built to the spec it will be operating.


There is a lot to the details of advanced battery chemistry and engineering. Probably why many here shy away from diving and DIY packs. Look at the following chart. It is a random one put you can see the different C discharge rating and the range of time rated at C rates.

I don't think whether or not the starter would take it is the issue here anyway. That fusible link business would be something fairly new. Any fusible link would be blown by heat which is a function of current times voltage so all you need is a way to limit those and such things do exist. So there certainly would be a way to apply 48 volts through such a device and avoid damaging the starter. How expensive that would be I can't say but it's certain it could be done.

The question was, why wouldn't the batteries be able to handle it? And that question hasn't been answered.

Jim

There's a simpler solution!

Just keep your start batteries always topped off by using a solar charge controller that has it's solar input hooked to your 48V house battery pack.

All solar charge controllers know how to correctly charge a lead acid battery.

This works because most solar panels are between 36-72V when they are producing power. Doesn't have to be a high power solar charge controller.

Here's a inexpensive one with blue tooth that you can control from your phone.

https://www.amazon.com/Victron-SmartSolar-Charge-Controller-Bluetooth/dp/B075NQQRPD/ref=sr_1_1_sspa?crid=32QDJCHHGN14G&dchild=1&keywords=victron%2Bmppt%2B75%2F15&qid=1634487075&sprefix=victron%2Bmppt%2Caps%2C218&sr=8-1-spons&smid=A2VHGGOHXF24LJ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEySldONjAwU1RVTFZDJmVuY3J5cHRlZElkPUEwNzQyNTAxMVNHQkpZSFU4TTZaSyZlbmNyeXB0ZWRBZElkPUEwMzk4NjQyUDRYMFBZWVlQRjRaJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1 (https://www.amazon.com/Victron-SmartSolar-Charge-Controller-Bluetooth/dp/B075NQQRPD/ref=sr_1_1_sspa?crid=32QDJCHHGN14G&dchild=1&keywords=victron%2Bmppt%2B75%2F15&qid=1634487075&sprefix=victron%2Bmppt%2Caps%2C218&sr=8-1-spons&smid=A2VHGGOHXF24LJ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEySldONjAwU1RVTFZDJmVuY3J5cHRlZElkPUEwNzQyNTAxMVNHQkpZSFU4TTZaSyZlbmNyeXB0ZWRBZElkPUEwMzk4NjQyUDRYMFBZWVlQRjRaJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1)

That's a good idea, but what if your start batteries just simply died? If starting from your house batteries was the only option, what would you do? Surely not punt.

Jim

Clifford said above.
You know the Delco 42 starter on your bus is a 900 amp 10 hp motor and they will draw those amps on a cold day I have seen higher, that is why lead batteries have cold cranking amps to turn that baby,The part I don't get is drawing a 100 amps from a 100 amp battery you only get maybe 30 seconds then drawing the same amps from a 100 amp battery would be like shorting one out I guess.

Don doesn't have a 42 he has a 39 like mine. :^ 

Quote from: Dave5Cs on October 17, 2021, 10:03:41 AM
Clifford said above.
You know the Delco 42 starter on your bus is a 900 amp 10 hp motor and they will draw those amps on a cold day I have seen higher, that is why lead batteries have cold cranking amps to turn that baby,The part I don't get is drawing a 100 amps from a 100 amp battery you only get maybe 30 seconds then drawing the same amps from a 100 amp battery would be like shorting one out I guess.

Don doesn't have a 42 he has a 39 like mine. :^

Still takes the same toque the 39 does it through the reduction gears to achieve the magic 60 rpms with less amps and those are 7-1/2 hp 

I understand Don sizing now I looked at a factory setup the largest cable on the system was AWG 2 with 6 LifePo4 , the Delco starter would do the AWG 2 in fast I doubt the AWG 2 would carry a 100 amps ,then the BMS looks like a weak link,the unit did not a boost switch either tying the banks together 

Quote from: freds on October 17, 2021, 09:14:10 AM
There's a simpler solution!

Just keep your start batteries always topped off by using a solar charge controller that has it's solar input hooked to your 48V house battery pack.

All solar charge controllers know how to correctly charge a lead acid battery.

This works because most solar panels are between 36-72V when they are producing power. Doesn't have to be a high power solar charge controller.

Here's a inexpensive one with blue tooth that you can control from your phone.

https://www.amazon.com/Victron-SmartSolar-Charge-Controller-Bluetooth/dp/B075NQQRPD/ref=sr_1_1_sspa?crid=32QDJCHHGN14G&dchild=1&keywords=victron%2Bmppt%2B75%2F15&qid=1634487075&sprefix=victron%2Bmppt%2Caps%2C218&sr=8-1-spons&smid=A2VHGGOHXF24LJ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEySldONjAwU1RVTFZDJmVuY3J5cHRlZElkPUEwNzQyNTAxMVNHQkpZSFU4TTZaSyZlbmNyeXB0ZWRBZElkPUEwMzk4NjQyUDRYMFBZWVlQRjRaJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1 (https://www.amazon.com/Victron-SmartSolar-Charge-Controller-Bluetooth/dp/B075NQQRPD/ref=sr_1_1_sspa?crid=32QDJCHHGN14G&dchild=1&keywords=victron%2Bmppt%2B75%2F15&qid=1634487075&sprefix=victron%2Bmppt%2Caps%2C218&sr=8-1-spons&smid=A2VHGGOHXF24LJ&spLa=ZW5jcnlwdGVkUXVhbGlmaWVyPUEySldONjAwU1RVTFZDJmVuY3J5cHRlZElkPUEwNzQyNTAxMVNHQkpZSFU4TTZaSyZlbmNyeXB0ZWRBZElkPUEwMzk4NjQyUDRYMFBZWVlQRjRaJndpZGdldE5hbWU9c3BfYXRmJmFjdGlvbj1jbGlja1JlZGlyZWN0JmRvTm90TG9nQ2xpY2s9dHJ1ZQ&th=1)

Did not want to mention the idea of keeping start batteries ready to start the bus, what a concept. lol What I do is simply have a plain old AC powered battery charger charge the starts if needed. Yes, using the solar powered lithium battery to charge the bus battery. Just plug it in like a house plug!

Can you use a Echo charger for the chassis battery when charging with solar ? my RV has a echo charger that charges the chassis batteries from the inverter and the banks are separated

Yeah but you guys are just dodging the question. Hey, what if a battery bandit snuck in overnight and stole your start batteries?  What if an Outlaw put a bullet through them? What if they fell out just as you made camp? What if they got struck by lightning? What if a quad-runner ran into them and shorted them out? How about then huh? Is there a way you could start your engine off the house batteries? A good old fashioned carbon pile could limit the voltage and current to the starter but how about the batteries? Are you guys saying there's a reason the lithium batteries couldn't be made to run the starter? I mean it sounds like that's what I'm hearing and I'd like to know why.

Jim

I'm advocating that with proper sizing of battery and connectors, there is no reason that a lithium house battery can't start the bus. The main consideration is peak current draw while cranking, that's it. I have jumped my starts from the house battery and it works but the jumper cables were not up to the current so got warm. Like I said as long as all specs are met, then no issue.


The other hillbilly method I have done in the past with fading starts was to start the generator to charge up the starts. Many ways to get sick starts well enough to crank the bus.


The easiest way is to just plug in a regular AC battery charger, take a nap, then start the bus and go. Not rocket science guys.

We can easily start the bus with either our two chassis start 8D hybrid wet lead acid or the house bank five group 31s wet lead acid. No lithium here - don't have those kinds of Benjamin's... The house bank is supported by 400W solar & the starts supported by 100W solar. The start & house banks can be switched to either or combined by blue sea RBSs for starting, house camping needs, &/or feed to the inverter. While OTR the house bank is dropped out & the starts power the roof air with 1/2 load on the engine 200A alternator. We're just all wet... :^
A total replacement of the entire seven batteries mentioned above is little more than the purchase of one 100AH Battle Born Lifepo. Serves us very well.

It would take a lot of Battle Born at 100 amp each to replace 1-8D starting battery with 1100 to 1400 amps, cost would be killer for the Battle Born used as starting batteries like 200 bucks for the 8D and 10 grand for the Battle Born.HWH hydraulic slides must use a lot of power Zach told me he needs to start the engine to extend his 4 slides or it cuts off after 2 times with his LifePo4 battery pack,I have not tried to extend or retract the slides on mine without the engine running it may do the same with my four Lifeline AGM 8D's  (1200 amp ) don't know

All our wet lead acid batteries were replaced a few months ago. We went with NAPA hybrids which gives great option to use either bank as start or deep cycle and they are all totally compatible with each other. The NAPA's have the highest AH/Cranking amps in comparison to similar competitors - NAPA group 31s are 105AH each & the 8Ds are 1700 cranking amps each. Prior to our current 4 stage smart charging these batteries were real close to 7 years old before weakening - we're good with that but will increase with the increased TLC they receive now. Yup, we're all wet...

Quote from: dtcerrato on October 17, 2021, 03:13:23 PM
All our wet lead acid batteries were replaced a few months ago. We went with NAPA hybrids which gives great option to use either bank as start or deep cycle and they are all totally compatible with each other. The NAPA's have the highest AH/Cranking amps in comparison to similar competitors - NAPA group 31s are 105AH each & the 8Ds are 1700 cranking amps each. Prior to our current 4 stage smart charging these batteries were real close to 7 years old before weakening - we're good with that but will increase with the increased TLC they receive now. Yup, we're all wet...

Don was DIY he probably has a 1/4 or less of the cost if he went out and bought Battle Borns

I followed Don's build. He spearheaded a unique design and has a primary off grid system. We just went for supplemental solar - that & the added inverter instead of genny power otr has decreased our dependency on the genny exponentially.

On the 5C, I tied the starts and house batts together as one bank. 8 6V Trojan golf cart batts. Works good.

LOL I guess I will tough it out because I am not going to install solar on the roof of my RV ,heck I dislike  the in motion satellite on the roof so much I am removing it   

Does the max charge rate of a battery increase when wired in series?

No when wired in series the voltage will increase but not the amps

Quote from: luvrbus on October 17, 2021, 07:05:06 PM
No when wired in series the voltage will increase but not the amps

Ok...so if a battery has a BMS and a max charge rate of 50 amps, what happens if 80 amps is coming in?

Asking for a friend.

Quote from: epretot on October 17, 2021, 07:14:42 PM
Ok...so if a battery has a BMS and a max charge rate of 50 amps, what happens if 80 amps is coming in?

Asking for a friend.

Could be wrong here, but I believe that amps are pulled and volts are pushed. In other words, it makes no difference how many amps are available to the BMS, it will only pull as many as it needs. Volts, however, will continue to push against it and cause all kinds of problems if they are too high.

What exactly are you describing when you say that there are 80 amps available?

The other variable that gets glossed over during the selling job...

A "BMS" is not some universal thing.

Just like if we used the term "fuel delivery" for your new car. What's to prevent it from being a 2 barrel carb, and not the electronic direct fuel injection you were assuming...

Try to find the parameters/performance/history/reliability of the "BMS"...

If the brains don't do what they are supposed to, the lithium bits get damaged, and/or dangerous.

Still too much wild west, carnival atmosphere, "trust us"...

happy coaching!
buswarrior

An example would be two solar chargers rated at 40 amps wired in parallel coming from 2 solar arrays.

I'm still researching the Lithium batteries. SOK has a more affordable lithium battery. However, it's max charge is 50 amps.

Hence the question about their capability wired in series.

Perhaps I asked the question wrong.

I think a better question is...

Does the max charge capacity increase when four batteries are wired 2 in series then paralleled together?

Forgive me...still learning the lingo.

Quote from: epretot on October 18, 2021, 05:20:26 AM
Perhaps I asked the question wrong.

I think a better question is...

Does the max charge capacity increase when four batteries are wired 2 in series then paralleled together?

Forgive me...still learning the lingo.

The max charge capacity of each battery will remain the same no matter how it's connected to the other batteries. Depending on how you connect them (series vs. parallel, etc) you will be raising and lowering voltage and amperage according to the equation watts = amps x volts, and the watts will be the constant for a battery equation.

The difference will be in the efficiencies of the various methods of connecting and/or the efficiencies of the type of charger being used.

my current set up

4 x 12 v starts and 6 x 6v GC for house and I can combine them all if needed for starts if needed  but when it is time to replace I thing I will go to the 8 x 6 v GC and use for everything on 1 system like  JC

dave

I don't get the LikePo4 charging and draws yet ,James told me the Lifeline you cannot charge with more amps than the LifePo4 is rated for .like jumping a 100 amp with a 200 amp alternator.I think you could work around that though by letting the alternator regulator controlling the voltage and amps needed but I may be wrong since Zach has a 100 amp alternator for his LifePo4s.Everything posted here is about solar and the LifePo4 charging and you need away to charge when the sun doesn't shine for weeks I would think a lot to learn for me,no solar on the van so they are going to charged by the alternator (140 amps)still don't have any idea how I can get the volts needed to charge the LifePo4 to full charge with the stock alternator,I have the same problem with my AGM batteries in the RV but it has a inverter so I plug it in the van doesn't have the inverter charger it has a piece of crap 4 stage charger   

What's this BMS business?

Quote from: Jim Blackwood on October 18, 2021, 07:56:41 AM
What's this BMS business?

Battery Management System to keep the LifePo4 safe in their operating range,it will disconnect the charging source if it detects low,high voltage or high or low temperatures or supposed to anyways     

Quote from: Jim Blackwood on October 18, 2021, 07:56:41 AM
What's this BMS business?

Or, Battery Monitoring System, which is NOT the same, but unscrupulous peeps will just throw the acronym and take your ca$h...

There are other prophets out there suggesting there is no need for a BMS to charge your lithium...

I sure do miss the engineers that used to hang here with us...

happy coaching!
buswarrior

Quote from: buswarrior on October 18, 2021, 09:57:14 AM
Or, Battery Monitoring System, which is NOT the same, but unscrupulous peeps will just throw the acronym and take your ca$h...

There are other prophets out there suggesting there is no need for a BMS to charge your lithium...

I sure do miss the engineers that used to hang here with us...

happy coaching!
buswarrior

Lol but some of those guys could get in outer space too, like the electrical  engineer that installed halogen lights in the ceiling and almost caught the bus on fire   

Quote from: epretot on October 17, 2021, 07:14:42 PM
Ok...so if a battery has a BMS and a max charge rate of 50 amps, what happens if 80 amps is coming in?

Asking for a friend.

Ah it is a bit confusing in this case the BMS would limit the maximum charge rate to 40 amps. The two solar controllers that you speak of have a maximum charge rate of 40 amps. Generally they are configurable for the output voltage so 40 amps at 12V it would be 12 X 40 = 480 , 24 X 40 = 960 or 48 X 40 = 1920 watts.

A 40 amp BMS is fairly wimpy you really want 100 amps or higher. With 40 amp BMS you would more and likely have to have multiple batteries in a series/parallel configuration to drive an inverter with enough power to run a microwave.

You generally want your house batteries to be higher than 12V, however that also generally dictates multiple batteries in series.

Most solar panels output between 36-72 volts, while you can get 12v solar panels they IMO are waste of money and time.

Solar charge controllers are generally first targeted by the output voltages 12/24/36/48 and by maximum solar panel input voltage; followed by the output amperage.

The maximum solar panel voltage is for when you string solar panels together in series, not something I recommend for bus nuts. As a partially shaded panel reduces the total output of all the panels in the string. Recently watched a video of relocated solar panels that saw drop in output from the shadow from an antenna guide wire in a series string.


Go to amazon and search for "victron solar charge controllers".

Note when sizing your solar panels you really can't have too many! (More power!!!). You want the biggest high power panel(s) that you can fit!!!


Here's a view looking back along the top of my bus:

(https://www.crystalpoint.com/cpdownloads/public/outgoing/Freds/SolarTopView.jpg)

Also note there is an energy tax for each stage in the system as charge controllers, batteries and inverters.

Note: a 400watt power will only produce that amount when all the ducks are in a row.

 I see people in Quartzsite washing and cleaning the solar panels on the roof that must be why Freds, never even thought they were that touchy 

A BMS function is totally different from a charge controller function. All the BMS does is make sure the batteries are balanced and in operating range and cuts off draw if below the set low voltage limit.


The charge controller is the circuit that manages the flow of power flowing into the battery and ensures the battery is not overcharged.


Generally, the solar charge controller is a separate device, designed and engineered into the charging side of the system. Well built lithium battery pack include a BMS inside the battery pack to ensure long life of the battery pack as the cells are balanced and the battery is kept from being drawn down too low or when too cold if outfitted with a temperature sensor.


More rare is combined solar controller and BMS functions into single device. The Electrodacus SBMS0 is such a device and what is in my system. Can not comment on pros/cons but it works very well for me in MY system and a lot cheaper.


As to DIY costs, 25% of retail is way too high. You can DIY today for around $125/kW, not $1,000/kW retail.