battery - prevention of acid

mshen11
mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
i was wondering is it safe to throw a towel on top of your battery setup (a big bath towel over all of your batteries)...

this way it absorbs the acid/spills and prevents it from sprending in a closed environment.

if thats not safe, would just laying a peice of plywood/cardboard directly on top of the setup be safe/effective (touching the batteries)?

Comments

  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: battery - prevention of acid

    I would be worried about tossing a towel on top... Acid+flammable materials can equal fire.

    The reason to cover the batteries is to prevent tools/etc. from falling on the batteries and prevent shorts.

    If you have problems with too much acid mess/mist... You may be overcharging/equalizing your battery bank. Also, make sure your plates are covered--but the electrolyte is not too full.

    There are some battery caps which are supposed to reduce the amount of acid mist coming from the battery.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • mshen11
    mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
    Re: battery - prevention of acid

    theres a lot of story how the acid vapors will destroy whatever is in the room (In my case garage - car, RE equipment, etc...) and it makes me scare.

    i dont have a fan to the outside (and HOA will now allow it) - so what is the next best thing to collect the vapors?

    i know it sounds like the best solution is prevention. how does one prevent overcharging/equalization when all the parameters are programmed in (other than physically being there for 10+ hours which is not feasible)?
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: battery - prevention of acid

    I would look at swapping out the battery(ies) to AGM. If that is not possible then look at putting the battery(ies) in a sealed box. Run a 1/4" ID hose from the top of the box to a window/crack in the garage that is higher than the battery(ies).

    Hydrogen is lighter that air so it will raise though the hose without the need of a fan. The fan is good/needed if you have a large battery bank.
  • mshen11
    mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
    Re: battery - prevention of acid

    can you define large (bank)? 1000amphr? 500amphr? 2000amphr? 100amphr?

    also would opening the garage door 2-3 inches be sufficient (w/ no fan)?
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: battery - prevention of acid

    Couple of points.

    If the towel does come in contact with acid, it will dissolve. I've tossed plenty of clothes that got "moth eaten" by battery acid over the years.

    Generally, acid doesn't mist out of batteries if you keep the caps on. What 'gasses off' is hydrogen & oxygen; neither particularly harmful although hydrogen is highly flammable and oxygen promotes burning so there is a significant fire risk.

    The most problem with acid outside the battery is when you take the caps off to check the specific gravity and inevitably drip some from the hydrometer. A bit of baking soda about to neutralize it (careful not to get it into the battery) is best. Neutralizing acid is the only safe way to deal with it; any method of 'sopping it up' just leaves you with something saturated with sulphuric acid.
  • mshen11
    mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
    Re: battery - prevention of acid

    well it well be scrap towels of course :) that would still pose a fire danger?

    then why do alot of people talk about acid spray/misting out?
    that reminds me of another question... :) after using the hydrometer... how do you "clean it out" for storage/safety around kids? do i drench the entire instrument in baking powder+water solution (if so, what is the mix) and rinse it out?

    is there something less messy like an electronic hydrometer?
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: battery - prevention of acid
    mshen11 wrote: »
    can you define large (bank)? 1000amphr? 500amphr? 2000amphr? 100amphr?

    also would opening the garage door 2-3 inches be sufficient (w/ no fan)?

    Anything over 500 HA would be large enough to produce a dangerous amount of gasses.

    I going to say , no. As the gasses will rise to the ceiling and stay there.
  • mshen11
    mshen11 Solar Expert Posts: 185 ✭✭✭✭✭
    Re: battery - prevention of acid

    are these gases fast or slow moving/dispersing? would opening the garage door 2-3mins a day fully be sufficient (no fan)?
  • n3qik
    n3qik Solar Expert Posts: 741 ✭✭
    Re: battery - prevention of acid

    That, I do not know. But it would be better than nothing.
  • Cariboocoot
    Cariboocoot Banned Posts: 17,615 ✭✭✭
    Re: battery - prevention of acid

    In an area the size of a garage, the gas from batteries shouldn't pose any problem. There simply won't be that much coming off. There shouldn't be, anyway; you'd have to boil the batteries dry. It's more of a problem when you have the batteries in a confined space like a battery box where there is also risk of a spark from the electrical wiring to ignite it. Lots of people have misconceptions about things and then expound them as though they are expert opinions. Technically there is a danger. But there's probably more of a danger from the gas in your car.

    A towel soaked with acid is still a towel soaked with acid - it's the acid that poses the danger unless it has been neutralized. Pick said towel up in your hands and you get acid on your hands (it's not particularly dangerous to most people's skin, but it is nasty).

    Rinse the hydrometer out with plain water. Sufficient dilution will also render acid essentially harmless. Remember; different kinds of acid act differently on other substances. We even drink acid, you know! Just not sulphuric (I hope).
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: battery - prevention of acid

    The waring on Misting Acid is to get the idea not to install a battery bank under your bed (quite a few questions here about under bed or in bedroom closet). And not to store your family antiques or install next to your Audio/Visual/Home Theater.

    Unless you way overcharge your batteries and generate lots of gasses (and misting) -- most of the corrosive effects are probably limited to right near/around the battery bank (i.e., don't install your $600 charge controller right next to the bank at cap level--move it a couple feet up/away to keep the Charge Controller clean (and don't install the CC right in the plastic battery box with the batteries).

    The warning about venting is to keep you safe. Will you get a hydrogen explosion in a garage--probably not--but it is possible in some cases (hydrogen rises and can collect under plastic tarps, etc... You have electric switches and (many times) gas water heaters, etc. in the area that can provide an ignition source....

    A few hundred Amp*Hours of batteries is probably not going to be an issue unless you have a flame/spark within a few inches of battery caps (typically a dropped tool, clipping onto the battery terminals with a charger/temporary load/battery tester/etc.).

    Have a few thousand Amp*Hours of of battery bank--you need to vent it correctly.

    We are trying to make sure that people are safe when working with battery banks... They store a tremendous amount of energy (large lead acid batteries have a scary amount of current available in a dead short) and are full of fairly strong strong acid which could blind somebody if they got a face full of it from a minor hydrogen explosion bursting a battery apart.

    Of course--your care has 15 gallons of gasoline in it too... Parked right next to the water heater (which is also connected to a natural gas pipeline). Batteries are just another hazard to be treated with respect.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • tallgirl
    tallgirl Solar Expert Posts: 413 ✭✭
    Re: battery - prevention of acid
    mshen11 wrote: »
    are these gases fast or slow moving/dispersing? would opening the garage door 2-3mins a day fully be sufficient (no fan)?

    Molecular hydrogen will rise very rapidly in any environment and either accumulate in a pocket where it can't escape, or seep out of the smallest of cracks. It's very unlikely that it would accumulate in the ceiling of your garage simply because your garage ceiling likely isn't hydrogen-tight, or the air movement inside the garage is enough to remove it.

    Really -- the risks are in small and tightly enclosed spaces, such as battery boxes, or with very large banks being floated at high voltages for extended periods of time.
  • Photowhit
    Photowhit Solar Expert Posts: 6,002 ✭✭✭✭✭
    Re: battery - prevention of acid
    mshen11 wrote: »
    well it well be scrap towels of course :) that would still pose a fire danger?

    then why do alot of people talk about acid spray/misting out?
    that reminds me of another question... :) after using the hydrometer... how do you "clean it out" for storage/safety around kids? do i drench the entire instrument in baking powder+water solution (if so, what is the mix) and rinse it out?

    is there something less messy like an electronic hydrometer?

    Acids rapidly disipate(? mix/dilute)in water, just suck up some clean water and rinse the outside a couple times and your good to go.

    If your like me (I surely hope not...lol) I always seem to have an extra half gallon of distilled water in my battery box that froze over winter, or I left the top off of between weekly checks and I no longer trust to add to the battery, but it's just fine for things like this...
    Home system 4000 watt (Evergreen) array standing, with 2 Midnite Classic Lites,  Midnite E-panel, Magnum MS4024, Prosine 1800(now backup) and Exeltech 1100(former backup...lol), 660 ah 24v Forklift battery(now 10 years old). Off grid for 20 years (if I include 8 months on a bicycle).
    - Assorted other systems, pieces and to many panels in the closet to not do more projects.
  • BB.
    BB. Super Moderators, Administrators Posts: 33,431 admin
    Re: battery - prevention of acid

    Don't mix baking soda and suck into the hydrometer--You should not need to neutralize the acid in the hydrometer, and any left over baking soda will go back into the battery the next time you use the hydrometer (and begin to neutralize it).

    If you need to rinse out the hydrometer--just pure water is enough.

    -Bill
    Near San Francisco California: 3.5kWatt Grid Tied Solar power system+small backup genset
  • halfcrazy
    halfcrazy Solar Expert Posts: 720 ✭✭✭
    Re: battery - prevention of acid

    I have run my 2 inch pvc vent straight up threw the roof with 2 90's it looks like a sewer vent pipe I bet you could slide that past the HOA
  • Vic
    Vic Solar Expert Posts: 3,208 ✭✭✭✭
    Re: battery - prevention of acid

    Personally, I would clean the battery tops (and perhaps sides) with a dilute solution of backing soda in water. About an ounce in a quart of water. Carefully clean the batteries with a shop towel or rag moistened with this solution. Periodically rinse the rag in the solution. Be careful to not slop the solution on or too close to the caps. Personally, I use a wide mouth plastic container with a tight top to keep the solution and rag handy. The red-colored shop rags (often made in South Asia) have a litmus effect (when exposed to acid, the red changes to blue). This is a convenient indicator of which droplets on the batteries are really acid and which are just water. When done neutralizing the battery surfaces, might be a good idea to clean them again with plain water. Keeping battery surfaces clean and acid-free is a good idea. Vic
    Off Grid - Two systems -- 4 SW+ 5548 Inverters, Surrette 4KS25 1280 AH X2@48V, 11.1 KW STC PV, 4X MidNite Classic 150 w/ WBjrs, Beta KID on S-530s, MX-60s, MN Bkrs/Boxes.  25 KVA Polyphase Kubota diesel,  Honda Eu6500isa,  Eu3000is-es, Eu2000,  Eu1000 gensets.  Thanks Wind-Sun for this great Forum.