Long stored NiCad packs

[Ty_Bower]

I've got a couple of very old NiCad packs. These guys were stored for a long time. One is showing 5.26 volts, which is just under .9 volts per cell. I'm thinking this guy might still be OK. The other is reading just over 3 volts, which suggests to me that at least two of the cells in the pack are dead or flipped.

I'm going to put both packs on the trickle charger at a couple hundred mA and see what happens. I could also hit them with the 4 amp fast charge, but I'm guessing that's not a good idea.

Or should I just pitch both of them in the recycle bin?

 

[SilverFox]

Hello Ty,

NiCd cells are very robust and often they can be revived after long term storage.

You need to do a 0.1C charge for 16 hours, then do a discharge to measure capacity. If the capacity is within 80% of the initial capacity, they are good to go. If they are below that, you can try another cycle and see if the capacity goes up. Keep cycling until there is no increase in capacity. If you are below 80%, recycle the cell.

I have some "new in package" NiCd D cells that are about 15 years old and have never been used. Some of them have come back to full capacity, and others have not.

Tom