I am in the process of fabricating new baggage compartment doors, I need to consider the following information I am requesting before making the final design.
I plan to have a good sized battery bank for inverter / solar power use, I do not know of the size of battery bank as yet, this is too far down the road in my conversion design and thoughts. The design for the air ventilation for the battery storage compartment is needed now so that I can plan the air flow design of ventilation through my baggage doors as I plan to do if the batteries should be vented from over the top of the batteries. The batteries will be totaly enclosed in their own compartment for safety in my design. What I am asking here is does the fumes of the battery rise or fall? should my battery bank be vented from top of the batteries coming from the sides of my new door design or should I design a vent through the floor??
If the ventilation is through the side of baggage door or through the floor, how much open area is recommended for good air flow, I plan to ventilate the battery bank compartment from one side of bus to the other for through ventilation if you do not recommended venting through the floor.
Thanks ahead of time.
Gary
Gary,
I have been looking at this recently for myself.
My plan is to put louvers, forward on one side and reverse on the other, to pull air through while underway.
Thsi design is very consistant with what I have seen it boats and buses to vent compartments.
This should also create a draft effect while sitting still if you have any air moving at all.
I would also put a 1" drain in the floor incase something spills or leaks. You could use a tailpipe piece like on a sink with the flange
end recessed into the floor to allow easy flow. This will also alllow you to wash off your batterys with a hose.
A good practice to get into since they will collect dust and other contaminents on the upper surface.
If only I lived in NJ, I here theres a guy up there with some pretty cool metal brakes in his shop. ;D
Cliff
Cliff,
Thanks for the input, I am sitting here now looking for some tips before starting out for the day. I am assuming that the ventilation path you recommend should be mounted as high or higher than the top of the battery bank?? Also thanks for the insight of the drain in the floor. Any more ideas on this, share them with me if you don't mind. My metal brake is sheet metal clamped between two pieces of 1 1/2" angle iron and bent with a mallet.
Thanks again,
Gary
I just did a google search on battery venting.
One article said to vent the compartment at the highest point so the hydrogen gases can escape.
Hope this helps in some way.
I just learned something. ;) ;) Thanks for the question.
Paul
Hydrogen gas is lighter than air and very explosive. Remember the Hindenburg? The OEM battery compartment on our MC-8 had small slots in the door skin near the top of the door and louvers in the floor. The louver openings face the rear of the bus. This was probably done to prevent water, dirt, etc. from getting in the compartment when the bus was moving and may have created a low pressure (Suction) to help keep gases from building up in the compartemnt. Hope this helps, Jack
Maybe a good source of information on venting and what is used.
http://www.newenglandsolar.com/catalog_pages/catalog54.htm
Paul
Gary,
I wonder how well, puting one set of vents low and one set high would work. Then whether the hydrogen gas is lighter than air would make no difference, there would be positive flow in either direction.
This might come in handy if the outside ambient temperature is warmer than the air inside the bay. As warm air is pulled in the upper vent, it would force the cold air, and along with it, the hydrogen out the lower vent.
If the situation is reversed, the natural tendency for the gas to rise would make the upper vent the escape route.
Just thinking off the top of my keyboard!
God luck and post what you have done!
Dallas
To all that have posted in reply, thanks, I also know now the importance of considering this information from the web site posted above by Dreamscape. Now the web site apparently is designed for one battery and I am unclear now also if perhaps this area they have used, 2'" in and 3"out for the ventilation is sufficient for large battery banks?? This final question is not necessary to have anwered today but a thought I hope that more experienced bus nuts can shed light on. Does the size of the battery bank make a difference for ventilation considertion? I do not necessarly want a huge opening though my bagage doors on both sides of my baggage compartment but I will do what is recommended from recommendations and experience of others.
Lots of food for thought here today, direction of air flow, (One vent forward and one aft through doors), (One higher vent and one lower vent on the opposit side), (Size of air intake and Exhaust), good grief, this was supposed to be easy but I love to just use experience to help decide.
Thanks for all the input, good grief you knock me out.
Gary
Gary,
Another option is to used sealed batteries, I think these are AGM, or if using lead/acid batteries use HydroCaps on the batteries. either option elenimates the need for venting. Jack
Gary,
One more thing.
If you use AGM's for your house bank you hardly need any ventilation.
My 10 battery sealed AGM bank looks great 1 1/2 years after install, no corroision from any battery breathing/venting.
All connections look like the day I installed them. :P
I am still venting the compartment though, as its not a perfect world. ;)
Just another thought.
Cliff
There I go, now another hurdle, ventless batteries to consider, more thought needed today, will just do the framing for outside of door, I believe just for back up sake, I will still install maybe the 2" diameter vent in and 3" vent out just for safety sake and eliminate any bad situations that could accientally occur, (Battery Burst etc.) I have no idea what could happen but as you all know at the extent of my conversion now I will use overkill in my design I am sure but my Grandaughter will have one heck of a coach her papa made for her.
I have to go to work now, thanks for the input, good information now considered by many I am sure.
Gary
Gary, a couple of sites you might want to review. Lots of battery information.
http://www.marine-electronics.net/techarticle/battery_faq/b_faq.htm#6
http://www.batterytender.com/connecting.php
http://www.uuhome.de/william.darden//
Remember, there are no batteries that do not require ventilation. They all have a pressure relief valve to relieve pressure in case the charge rate gets too high. Unfortunately the only way you find something out like this is when the charger circuit voltage gets too high and the battery starts gassing. Then if you have anything in the compartment that could cause a spark, BOOM!
I like Dallas's suggestion best and also I would recommend you seal the compartment in the middle so that nothing but batteries are in that compartment. The other half of the compartment could then be used for storage or whatever.
Richard
Hi Gary,
This link also gives you lot's of battery info..
http://www.marine-electronics.net/techarticle/battery_faq/b_faq.htm#6
Nick-
The nice thing about AGM (Absorbed Glass Mat) sealed batteries is that they don't gas, are rated for airplane travel (like on a wheelchair for instance), and can be mounted in any position with upside down not preferred. Think how much more room you could have by mounting the batteries on end? I saw a production sportfisher yacht with big Cats, and the 2-8D starting batteries for each engine were mounted on a shelf just under the floor on their sides. Opens up many possibilities. Even though the AGM (like Lifeline) batteries are not cheap, they are vertually maintenance free and have a limited 5 yr warranty. Good Luck, TomC
Gary, I created only a 1 1/2" outlet for my battery box, BUT I have my inverter setup to turn on a ventilation fan once the voltage exceeds 26 volts. This happens if I'm charging off the inverter or off the bus alternator. This way I get positive ventilation any time charging is happening.
Quote from: Brian Diehl on November 28, 2006, 09:23:36 AM
Gary, I created only a 1 1/2" outlet for my battery box, BUT I have my inverter setup to turn on a ventilation fan once the voltage exceeds 26 volts. This happens if I'm charging off the inverter or off the bus alternator. This way I get positive ventilation any time charging is happening.
How-did-you-do-
that?? Wow!
You never cease to impress me, Brian D., with your "bootstrap" engineering. I think between you and Gumpy, the Twin Cities is pretty much
covered when it comes to bus-gineering.
Bravo!
Brian B.
Hi Brian B.
My inverter is an Outback FX 24v model. It has a built in feature that allows one to drive different types of output devices through one 12v connection port on the inverter. The port can be used as an auto gen start or .... I use its ability to be turned on at a specific voltage to drive a brushless 12v computer fan that pushes air in the battery box at the bottom and out the top where my 1 1/2" vent tube is at. The vent tube then gets routed into the MCI battery compartment where it is exhausted out the battery compartment louvers.
Man oh Man,
I come in for lunch and wanted to check for additional information to my post but never expected so much informative places to go for additonal information and personal design information also of some of those who have done this project. I will not take the time to go to the web sites sent to me right now but will after working on bus this evening, I am Just making the main door framing today and all this takes time and any cut out openings needed can be done as of tomorrow, roghing in the doors is priority today.
In my mind from working all morning here is what I think I will do but that can and probably change tomorrow. I Think I will put a 2" vent on the bottom with louvers pointing to the front of bus or downward, and a 3" vent at the top of my battery compartment with louvers pointing to the back of bus or downward to the ground. These vents will not be so large they take away from the cosmetic view of my doors, I hope. The vents will sealed to the door each time the door is closed by Trial and error. I will vent my battery compartment only as a safety precaution no matter what kind of battery I use, I am sure I will not be able to afford the real good ones at first as I also have to replace every tire etc. and this is all $$$ that is difficult to accumulate when retired.
So if I have to use lesser quality batteries no matter where I get them I can upgrade when ever it may become possible in the future but the venting will never be a waste of time to me for the safety factor alone. My battery compartment will be isolated from my inverter and every electrical componet or compartment for my bus power system for the same reason, I know, this is over kill but as Fast Fred used to always say, do it my your way and be happy.
I am putting all your information offered today in perspective and trying to incorporate it all into a perfect arrangement I will be proud to show you all if I ever ger "R" done. What a monument!!
Thanks again for all comments, suggestions, websites with information I know I can study for more ideas and just having you all involved.
Now I got to get back to work for the afternoon.
Gary
Gary
One other consideration make sure you don't set up a BBQ close to battery compartment as we all usually run a gen set or charge batts off land line when sitting and a open flame and hydrogen gas makes for a exciting evening at the imprompto bon fire.
LarryH
Don't forget the benefits of having a plainly marked container of baking soda located near the battery compartment. I suggest about two or three pounds, in a plastic container, kept readily available, somewhat like you might keep a fire extinguisher available for emergencies. If you have an acid spill, the soda, followed by flushing with water, will neutralize the acid. I keep it in my shop.
Would it be a good idea to tie the battery vent into the waste tank vent?
This would get the corossive gases above from the bus without another unsightly vent.
Another thought about fans is to use a bilge fan (I think they are explosion proof) from a boat & have it come on whenever the baterys are charging or discharging.
Looking forward to the next update!
A lot of great ideas come out of this post and thanks to all. Kyle, I like your suggestion but maybe a little feed back from others on this, I am not sure of the extent of having a gas build up some place within the plumbing in elbows etc. and also of the gases from the waste tank mixing, maybe not problem but lets run with this idea and see what others think if they don't mind posting?? I like the idea, have to think on it and maybe get other thoughts about it. As far as unsightly through the door vent. this will be sort of small, but the sight of this vent system if will not bother me as much as not being safe without the air ventilation system.
I have gone and looked at all the sites that you all posted her also, Man I am tired but more educated.
I definately will not have my barbecue next to my battery bank or air vent exhaust, and will also have the baking soda ready. Other legitimate suggestions apprecaited.
an explosion proof fan is a major consideration, good inforamation here and thanks again.
Gary