Battery acid spill

[TheBeastie]

Not really a Defender question but the battery did come from The Beastie originall!

I lent a spare battery for a big radio event and when it came back chap said he thought it had tipped (fair enough these things happen). Then discovered the big insulated bag I use (so it can operate in very cold conditions) had most of its stiching rotted and the inner polystyrene casing was swimming!

Sluiced all out with water then cut the battery out out of the packing (very tight fit).

Most cells were pretty empty so filled up with deionised water and put onto charge. Seems to have taken and given it a 1hr discharge on a 50W halogen bulb before re-charging.

Question is - the acid in the cells will now be very dilute. Will this rebuild through the chemistry (think not)/ Will it affect charge holding capacity (suspect it will). Should I empty out fluid currently in it and then re-fill with sulphuric acid and if so where would I get the acid?

Thanks

Malky

[simonr]

Yes, Yes - and a battery specialist / on line.

The concentration of the acid is important. Topping up with de-ionised water is ok as the water loss is through evaporation. Only the water evaporates - so you don't need to add acid.

Following a spill however, you do need to add acid.

I've bought acid from a local agricultural supplier but you can also buy it from commercial battery suppliers (Manbat Ltd) and most Fork-Lift specialists.

Si

[TheBeastie]

Thanks Si

Will need to get some acid then and also work out a way of draining the original cells (suspect tip it upside down into a plastic bucket then lots of bicarb of soda.

Help much appreciated and delighted both my hunches were correct!!

[Happyoldgit]

Moving this so it gets a wider audience...

[rovernut]

Always pour the acid onto the alkaline never the other way round.

Alkaline when put into acid can explode into a large ball of froth.

[martyn668]

I think you can get acid "tablets" from motor factors. They're called something like "battery aid". They're used to give a pep to sluggish batteries, so I guess they're some sort of concentrated acid. No idea if they'd be any help.

[Simon Smith]

Having watched battery recycling plants at work, they used to just smash them and the acid went into the drains, it is after all relatively dilute and basically the same as most drain cleaners anyway, though I would flush it away with plenty of water. (Not saying this is now legal though) Normally adding water to acid is a no no, but the fact that we can do this safely when topping up shows how dilute it is.

As for Acid most garden machinery places will keep it too, we do as nearly all the replacement batteries are sold without acid.

[Tanuki]

If you've lost acid it must be replenished with acid.

My recommendation would be to drain off all the liquid from the battery, then replenish with fresh acid.

Then do a full charge with an intelligent charger that shuts-down to trickle when the battery's terminal-voltage starts to rise.

Once it's done this, then use a hydrometer to check the specific-gravity of the acid in the cells is within the values published for your battery. Remember you need to calibrate the specific-gravity reading for actual battery temperature.

See here:

http://batteryuniversity.com/learn/article/charging_the_lead_acid_battery

for some good guidance.

[jimyd]

Not quite sure how they get away with it, but take a look on ebay, delivered straight to your door for not much money!!