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My stubborn Sealed lead acid battery refuses to charge!? Answered

Just the day before it was working perfectly fine! And all of the sudden it doesn't! Its about 10 Amps and i was planning to use it but know it wont charge. Its about 2 times wider than those batteries that alarms use(look in that big box in the wall there is a lead acid battery in there) in my case i had 2. Its kinda like the one in the picture,Except a bit taller


i bought a camera from a neighbor and it had two SLA batteries (dead). i decided to take one apart to try a new project and found out why i thaught they werent working. upon opening the battery fully i discoved a greenish / white powder on my chem gloves. i belived that this was the lead acid so to test it i put a tad on my arm and found out good news. it was the lead acid because it burnt like hell like i had read it would. after washing of my arm i decided that the whole thing was stupid and now a breathing hazard because it wasnt a paste anymore like i thaught it used to be when they where new. i ended up buring it in my backyard. so all i could think was that you need to put water in it to let current flow through it and thus charge it.

Thanks, I am Warned now to never take an Lead acid battery apart >_

Well simple put your battery is dead and need a new one. There are circuits out on the web called battery zapper, which can zap your battery back to life.

The battery zappers don't seem to work for me... It is probably they don't have enough charge to properly zap the battery.

use a desulfator (a circuit that pulses 50v at 1khz)or make one!

that is exactly what i am making. i bought everything from digi-key and it came 2days later - i was expecting it to be 2 weeks!(uk).

Cool, that happens to me sometimes... :-D

Maybe your battery is beyond zapping. I know this battery are dear. The only way to fix it the problem is to buy a new battery. Also to buy a decant battery charger design to charge seal lead acid battery.

Also do zappers work for lead acid batts? I thought it was for NI-CD

No you can get zapper for seal lead acid batteries, are you sure it a seal lead acid battery. If it a seal lead battery then you do not need add water, due it being sealed.

lol I have never had to refill a seal lead acid battery before and I didn't knew it was even possible.

Maybe like I said I never refill a seal acid battery, if it didn't work for me I always got a new one.

When i shake the battery i hear some rattling inside does that mean i need to add water?

I have that same problem... :-(

Also my battery was from a dead UPS