Is it worth reconditioning NiMH batteries?

[bullpup]

The phone system in our house all (4 of them) work off rechargable AA batteries. I presume that the baterries in the phone are always on some kind of trickle charge. These batteries have been in the phone for about 2 years. Sometimes I would swap out these batteries and put into a mouse or small electronic device but for the most part they have been always on charge.
I was planning to have these batteries as the first use in a blackout since they were charged and I thought good for a flashlight.
Today I put them in my new BC-900 charger to test the voltage. Everyone of them looked great at around 1.17. When I put them into the 500 Ma discharge cycle. I noticed within a minute the voltage droped to .92 and a minute latter the charger said charging all four batteries. I guess the 500 ma was too much load for them.

Should I just toss them? I know the charger is sitting on a concrete floor in the basement so I am not worried about the fire but should I consider these batteries dead?

 

[SilverFox]

Hello Bullpup,

I recycle my cells when they fail to give me 80% of their initial capacity.

If you want to play... You can run a few charge/discharge cycles to see if they will come back. I would suggest using the 100 mA discharge rate for the first two cycles.

Tom

 

[9volt]

AA NiMHs are about $1 each at batteryspace. I would toss them if they started acting up.

 

[bullpup]

IS that 80% capacity of volts or Milliamps?

Hello Bullpup,

I recycle my cells when they fail to give me 80% of their initial capacity.

If you want to play... You can run a few charge/discharge cycles to see if they will come back. I would suggest using the 100 mA discharge rate for the first two cycles.

Tom

 

[SilverFox]

Hello Bullpup,

Capacity is given in milli amp hours, or mAh.

If you discharge a cell at 500 mA for 1 hour and it ends up at 0.9 volts at the end of that hour, its capacity would be 500 mAh.

Tom

 

[bullpup]

So 0.9 volts is considered the end point fot NiMh batteries? If so, this is making sense, Just ordered 8 AA and 4 AAA eneloops from amazon for $37 with free shipping. Hopefully I will have better luck with these.

Hello Bullpup,

Capacity is given in milli amp hours, or mAh.

If you discharge a cell at 500 mA for 1 hour and it ends up at 0.9 volts at the end of that hour, its capacity would be 500 mAh.

Tom

 

[VidPro]

Deleted

 

[VidPro]

Should I just toss them? I know the charger is sitting on a concrete floor in the basement so I am not worried about the fire but should I consider these batteries dead?

dont sound so good, if i had to dissasemble to get TO them, i would change them now, if its easy in easy out like your indicating, i might run them on a "refresh" cycle and see what happens, if i had the charger time.

myself i would drop them further than that thing does, even sloooowly, there is a way to drop them slowly to .4v which can "Cycle" the extensivly voltage depressed parts. Its not documented in specs, but it can squeese out some extra operation.

based on the TITLE "is it worth it" heck no!, but you will get somewhere.