How will I know when to discard 'ONE' rechargeable battery?

[kenny]

All my devices use 3 to 6 AA batteries.

I've bought many Panasonic Eneloop AAs and a charger.
I LOVE them.

but ...

How will I know when it's time to send one, (not all 3 or 6) to battery heaven?

 

[JulieN]

Re: How will I know when to discard 'ONE' rechargeable batte

Voltmeter?

 

[kenny]

Re: How will I know when to discard 'ONE' rechargeable batte

Voltmeter?

I think even a nearly-dead rechargeable will charge up to the same voltage as a new one, but just won't hold the charge long.

But then hell might have frozen over and I could be wrong.