reviving old nimh

abhi555

Newly Enlightened
Joined
May 27, 2006
Messages
43
Location
Idaho
I had very old rayovac niMh battery. Eneloop charger will always refuse it, but I used to charge with Nitecore. But it started giving error with nitecore too, as voltage dropped to 0.73. I read somewhere on prius battery thread that one guy drilled cells and injected distilled water into cell to revive it, closed the hole with soldering (I used jbweld but it need certain position to charge). The theory was battery fails due to electrolyte dries up due to high temp while charging.
I got limited success (battery charges but lost its "LSD").
Anyone tried or wants to give a shot and post results?
There is no exact science: how much water cause I don't know original weight or really know if water is lost from electrolyte.
 

abhi555

Newly Enlightened
Joined
May 27, 2006
Messages
43
Location
Idaho
never mind. Quick search on forum there are posts like these. It's not worth it it seems.
 

ChrisGarrett

Flashlight Enthusiast
Joined
Feb 2, 2012
Messages
5,725
Location
Miami, Florida
never mind. Quick search on forum there are posts like these. It's not worth it it seems.

"He's dead, Jim."

Just start over like everybody else does. At some point, older cells/batteries are more of a hassle than the expense of buying new ones.

Chris
 

Lynx_Arc

Flashaholic
Joined
Oct 1, 2004
Messages
11,212
Location
Tulsa,OK
I have run older nimh through many refresh cycles and at times recovered part of the capacity lost on them but most often they are weaker and have higher internal self discharge typically relegated to light duty from then on. IMO if you get 100 cycles out of a nimh battery and it starts acting up time to just call it quits on it as you've already saved a bunch of money vs alkaleaks.
 
Top