what is the best rv deep cycle battery? Trojan t-105?

Oregonconversion · May 17, 2009, 11:56:10 PM

I have heard that these T-105s are the best bang for the buck.

I am looking for something that will last many many years. I do not want to spend over $1000 for my battery bank... but I will if it will save me money in the future.

Any help>?

JohnEd · May 18, 2009, 12:59:51 AM

I just want to encourage you to keep in pursuit of this answer. The answer isn't straight forward. Has some math in it. Different types of bats will tolerate a different number of discharge/charge cycles before they fail and at that the number of cycles varies according to how deeply you discharge them. Sean had a post a while back that laid out all the details of the selection. You can easily figure how many $ you spend for each charge/amp hour delivered, etc. Now if you can get different prices on different types of bats you can offset quality with cost....sometimes. I think all this will be more clear when you see his "formula" for bat cost. Sometimes the cheapest bat costs you much more in the long run and the deep guys last for many years. The forklift bats go for 10 to 15 years, I have read, but certainly don't know

Sean is in Orygun, as we speak. I don't know if he is headed north or south on I5 but you might arrange a "hook up" with him for an in person review.

Are you planning to attend the "Bus In" gathering in Rickreel, Or.? Lots of bus's there in June, I think.

Good luck,

John

rv_safetyman · May 18, 2009, 04:36:32 AM

There is a great deal of battery discussion on this board and BNO. Lots of opinions (and some good information - those two things are not always the same).

Many folks will recommend the golf cart batteries at Sams as the best bang for the buck. Some will say that AGM is the best buy since you don't have to do maintenance and they have some great operating characteristics. Obviously, you will need a true deep discharge type battery. The so called marine start/deep discharge batteries will not give you good service.

I went the Sams golf cart battery route. Pretty sure they were made by Exide. I have 8 and that is pretty marginal, but I have a some pretty good loading (domestic fridg., quite a few computer type things, non-flammable lighting {could not resist Bob}). My plan was to run with these for a few years until they died. They are still going strong after about five years (the first two were during the converting and they had some bad treatment during that time).

My real reason for posting is to say that you need to protect your investment with a GOOD state-of-charge meter. I use the TriMetric by Bogart Engineering (http://www.bogartengineering.com/). I try to never let my batteries get below 50% state-of-charge.

Trying to tell your battery state-of-charge with a simple voltmeter is not at all accurate. There are lots of technical references on the subject, but the simple explanation is that battery SOC can only be measured with a voltmeter IF the battery bank has not be charged or discharged for several hours and our systems don't operate that way. You could use a hydrometer to determine SOC but that is a real pain.

If you don't go with AGM, you will need to check the water level frequently and add DISTILLED water as needed.

If you treat any properly applied battery bank (proper type and capacity) properly, it will last many years.

Jim

rv_safetyman · May 18, 2009, 05:50:10 AM

My previous post was trying to say that how you treat your batteries is as (or more) important than what you buy.

I left out one other main factor: charging. You can really reduce you battery life by improper charging. A good inverter with a three stage charging system is your best friend.

In the past year, I have added a dedicated alternator for the house battery bank. Prior to that I only charged from the inverter (no connection to the regular engine alternator.

Since I made that change, I notice that I have to add water more often.

I do not use a standard 110 volt battery charger on my house bank. Some folks do, and I think that can be a real problem if you use a cheap charger (without three stage). If you leave a cheap charger on for long periods of time, you will cook the batteries.

Jim

belfert · May 18, 2009, 06:05:52 AM

I'm not convinced that paying $50+ each additional for the T-105 over the Sam's Club 6 volt battery is worth it. Even if you have to pay $40 for the membership you'll come out ahead on one battery.

AGM is the ideal way to go, but the price goes up, way up. Some battery prices have come down with the price of lead, but most are still way up strasosphere.

luvrbus · May 18, 2009, 06:19:35 AM

I guess I am the only person that has problems with AGM batteries the 2 sets of Lifeline I have had never gave me good service.
Maybe the AZ heat who knows but I am back to T105's now just check the water they will give you years of good service the 1st set of 105's lasted 8 years.
Check the cost of the amp hrs and ask is it worth it AGM batteries cost over 2 bucks per amp hr the 105's are less than buck good luck

junkman42 · May 18, 2009, 06:29:50 AM

Just a note to give You an possible option. I have 8 t-125 trojans which I bought from a trojan distribution center for less than 70 dollars each. They were 6 months old and stamped blems. The catch is no warranty they are Yours when You walk out the door. I used my digital voltmeter to select the eight I bought. Worth the risk to Me and they are so far perfect. John

kyle4501 · May 18, 2009, 06:39:02 AM

We called around to find out who was supplying the local golf courses. I told the salesman I was wanting them for my RV & was paying cash, he gave me a great deal.

He even provided me with the newest date coded batteries he had.

We put special caps on them to minimize water loss.

Biggest thing I would advise is to locate the batteries where it is easy to check & add water.
Batteries don't tolerate abuse & don't offer any forgiveness for unintentional abuse either.

Second biggest thing is to get a good charger, the life of your batteries depends on it! Most alternators have a crude regulator (the voltage & charge rate are not optimized) & will not be what you need for long battery life.

If you're the type who has to have the latest battery technology, then get that, whatever it may be.

Otherwise, I'd suggest starting with the t105 & evaluate how they can fit your needs. If you can accommodate their requirements, use them. There is a reason they are still in wide use.

junkman42 · May 18, 2009, 06:54:56 AM

Kyle, where do You get special caps? Am interested in loss of water. Regards John

luvrbus · May 18, 2009, 07:16:01 AM

John, you can buy the hydro caps from www.windsun.com I don't know if they are worth the cost or not never used them good luck

kyle4501 · May 18, 2009, 08:11:57 AM

We used the water miser caps
http://store.solar-electric.com/batwatmiscap.html

The hydro caps have a catalyst that can be ruined if it gets too hot, so it has to be removed before the equalizing cycle. Dad doesn't want to think about stuff like that, hence the choice for water miser cap that is easier for his needs.

Oregonconversion · May 18, 2009, 08:25:45 AM

I currently have a xantrex RV-3012 inverter with a good 3 stage charger.

I would love to have maintenance free AGM batteries, then I could build my battery box all the way through the bay and not worry about them. Will these last as long as the 105s?

What is a good AGM battery? What do they cost?

luvrbus · May 18, 2009, 08:38:25 AM

Try, www.windsun.com you can find prices for different Agm brands of batteries along with the ratings good luck

Ray D · May 18, 2009, 08:42:44 AM

8-D AGM's are going for about $500.00 now

Ray D

belfert · May 18, 2009, 08:48:04 AM

www.thesolar.biz has the Universal Power Group 8D AGM batteries for $370 each. They are Chinese, but I understand a lot of batteries are starting to be made in China.

The folks over at The Solar Biz probably wouldn't sell these if they had problems with them. They seem to be really good people.