What's new

Bringing a battery back from death.

Toreadorranger

Atomic Test Lab Rat
Joined
May 21, 2020
Member Number
874
Messages
1,060
Loc
CT
My project truck had a new set of batteries put in it in 2016, then I parked it in the garage to start building it. Of course I stupidly left the batteries in it sitting this entire time. What are the odds I'm able to save them? I pulled one out yesterday but none of my chargers will attempt to charge since the voltage is so low (<1V). I figure I can "jump start" them to try and get the voltage up high enough to charge. Am I wasting my time or are they past saving.
 
I take mine to an autoparts store and have them throw it on a charger, usually theirs are sometimes able to bring it back from the dead.
 
Optimate chargers work really good to bring back dead batteries, both gel and lead-acid.
I have a optimate 3, the voltage is too low for it to kick on. I guess I'll try and get a little bit of voltage in it then use that to see if it can recover.
 
Well I hooked it up to my daily and gave it a jump and the optimate recognized it after. Now we wait.
 
I have a optimate 3, the voltage is too low for it to kick on. I guess I'll try and get a little bit of voltage in it then use that to see if it can recover.

Hmmm... haven't ran into that before.

I've brought back batteries that have been dead for years. The lead acids respond quite well. The gel-cells are about 50/50.

I've got an older Optimate 3 and an Optimate 6. Had to get a second one, friends and neighbors are always borrowing one.
 
Your chances of recovery depend on how long they've been flat for. With lead acids when they're discharged for a long period of time the sulfur in the acid falls out of solution and ends up forming an impermeable layer of lead sulfate on the plates. When this occurs the only real way to fix them is to melt down and remake the plates.

As for recovery charging you really need a manually controllable charger with a constant current mode.
General rule of thumb is to charge with the current limited to 1/10 of C1, ie: 8 amps for an 80AH battery until the battery voltage stabilises (usually around 17v for a 12v battery) and then charge for a further 8 hours. This technique will boil the battery so make sure make sure you follow necessary safety precautions that take into account hydrogen venting and potential acid spill.

SAFETY SHIT!!!!!!
NEVER use this technique on a sealed battery! It is only suitable for use on fully vented or valve regulated lead acid batteries.

The battery WILL vent hydrogen gas and potentially acid so make sure you charge in a well ventilated area or use appropriate extraction and NEVER leave the battery installed during charging.

Always check electrolyte levels (in vented wet batteries) prior to charging and top up with distilled water only, you can correct the SG after charging if needed.

TL/DR
Don't be a dumb ass when charging batteries or you'll blow your shit up! :homer:
 
Your chances of recovery depend on how long they've been flat for. With lead acids when they're discharged for a long period of time the sulfur in the acid falls out of solution and ends up forming an impermeable layer of lead sulfate on the plates. When this occurs the only real way to fix them is to melt down and remake the plates.

As for recovery charging you really need a manually controllable charger with a constant current mode.
General rule of thumb is to charge with the current limited to 1/10 of C1, ie: 8 amps for an 80AH battery until the battery voltage stabilises (usually around 17v for a 12v battery) and then charge for a further 8 hours. This technique will boil the battery so make sure make sure you follow necessary safety precautions that take into account hydrogen venting and potential acid spill.

SAFETY SHIT!!!!!!
NEVER use this technique on a sealed battery! It is only suitable for use on fully vented or valve regulated lead acid batteries.

The battery WILL vent hydrogen gas and potentially acid so make sure you charge in a well ventilated area or use appropriate extraction and NEVER leave the battery installed during charging.

Always check electrolyte levels (in vented wet batteries) prior to charging and top up with distilled water only, you can correct the SG after charging if needed.

TL/DR
Don't be a dumb ass when charging batteries or you'll blow your shit up! :homer:
That's exactly what my $25 "automatic multi vultage" Chinese battery charger does. I alwasy thought that trying to bring a 12v battery to 15+ volts was kinda hack but I guess not. I'm not sure if that behavior was intentional on their part or not but that certainly explains my improved luck with recharging dead shit since I got it. :lmao::lmao::lmao::lmao:
 
A trick i heard, was that since the plates get corroded when sitting dead, you give the battery a single drop from 18"-24" on a concrete floor to break the crusty shit off. Makes sense, so if I have a "nothing to lose" battery, it gets a healthy drop, then attempt charging
 
A trick i heard, was that since the plates get corroded when sitting dead, you give the battery a single drop from 18"-24" on a concrete floor to break the crusty shit off. Makes sense, so if I have a "nothing to lose" battery, it gets a healthy drop, then attempt charging
I wonder if a paint shaker would work. :laughing:
 
Somebody once said to reverse polarity for a second on a dead dead battery to blast all the shit off the plates, but I guess you've got to have a setup that can handle the potential arcing
 
Purty sure I posted this one "over there"
Dump out the electrolyte straining it through a paint funnel\strainer get it all out.
Start rinsing out the battery case with fresh h20 (anal retentive guys use distilled) rinse all the trash out and refill.
Do the recharge dance and "hope":smokin:

Some of you old saddle tramps may remember
"The Barstow battery trick" :beer:
 
A trick i heard, was that since the plates get corroded when sitting dead, you give the battery a single drop from 18"-24" on a concrete floor to break the crusty shit off. Makes sense, so if I have a "nothing to lose" battery, it gets a healthy drop, then attempt charging

Somebody once said to reverse polarity for a second on a dead dead battery to blast all the shit off the plates, but I guess you've got to have a setup that can handle the potential arcing

Purty sure I posted this one "over there"
Dump out the electrolyte straining it through a paint funnel\strainer get it all out.
Start rinsing out the battery case with fresh h20 (anal retentive guys use distilled) rinse all the trash out and refill.
Do the recharge dance and "hope":smokin:

Some of you old saddle tramps may remember
"The Barstow battery trick" :beer:

I've heard of all 3 of these working, and I've done the drop method with slight success though I only did like a 10-12" drop.

But more often I just use the dead battery as an excuse to buy something better. 😁
 
Go garage sale shopping to an old fuck who's wife's selling his tools and garage stuff, therein you'll find a 40 year old battery charger. Buy it. It'll be 5 bucks, or so. Then use it on the 'dead' dead battery. you can thank me later. ... It'll tend to cycle 'on/off/on/off' but it'll put a charge into the battery at basically zero volts. after an hour or two, you can switch over to a modern charger if you want, but, I've kept them on these all day at times.
 
Top Back Refresh