Bringing life to used batteries

[redtide361]

I purchased a cart with basically dry batteries I've added distilled water and have done the proper charging techniques and have gotten them to hold a charge about 54-55 volts. But once I go about 2.5 - 4 miles I'm down to 45 volts and the cart is sluggish. Has anyone bought the battery acid replacement pack from your local battery/ automotive store??? And if so did it work. I think maybe if I remove the electrolytes and safe them for later use I can put the acid then charge and top off from there to get atleast double the drive time. ???? I'm hoping someone might have tried this

[LukeL]

I’ve tried it. Many times. It’s hit or miss. If the batteries are relatively new, in great shape, not swollen, and are just low on fluid, adding acid gives you a higher rate of success.

If the batteries are trashed, don’t waste your money. How old are they?

[redtide361]

They look great I'm not 100% how to use the date code for interstate batteries... but I almost feel like they where ordered online and never filled up. When I opened them I saw no fluid but also saw no discoloration, residue or corrosion on the plates they looked like nice clean metal. I purchased the cart from a lady who's father passed away all she knew is that the cart would only drive like 10 minutes then she would have to park it for 30 minutes to get back home and she parked it for 2.5 months then I purchased it from her.

[redtide361]

So I'm thinking try the battery acid. I'd like to get these half way decent for my 36v project slammed chop top series cart and use 7 of them. I scored this mint mpt 48v pds workhorse and like enough to buy new batteries lol!

[redtide361]

This is a pic of batteries from when I 1st got it home and started dissecting it.

[Mooncarter]

No way to tell from that photo, but I'm almost 100% sure they were not purchased without electrolyte. Do your thing with that and I'm all ears and eyes to see how it turns out. Hope it works and please tell us your results.

[redtide361]

Found the date code, called a main interstate battery distributor and got verification they are 2015 batteries. So their not as new as they looked just well cleaned but not maintained lol. Any way I picked up three 6 quart containers of battery acid. I'm thinking straight up acid no water. I'll keep yall posted. Any tips, concerns, questions or advice is all welcomed. Btw I am a senior technician and systems integrator for a living and I'm always willing to help anyone with control wiring or info on dc circuits or questions on troubleshooting anything control or dc voltage related which is basically a masters in diagnosing a sick cart. Thanks for all the help guys I've bought a few project carts that aren't running and fixed all of them thanks to the guys here. That's why I offered to help out.

[Mooncarter]

Please keep us posted on your results.

Your credentials are impressive!

[JohnnieB]

The batteries pictured are Interstate GC2-XHD, which are rated at 232AH.


The electrolyte is roughly 30% sulfuric acid by weight and will have a specific gravity of about 1.277, but the battery acid typically sold in auto parts stores has a SG of 1.265.

Each battery will hold about 6.5 quarts of electrolyte, so 39Qts are needed. At $5/qt, that will be $195 for electrolyte that isn't as concentrated as needed.

More concentrated sulfuric acid is available (SG 1.3 and 1.4) through chemical supplies, but don't know prices.

[swb713]

JohnnieB ... You Sir, are an invaluable source of information.