Hello All!
I hope this note finds everyone well & enjoying today!
Almost two years ago, I installed new generic cells in a cordless screw gun's battery packs (9.6 volt NiCAD).
To equalize the cells in each pack, I first charged them as slowly as possible for about 16 hours (100 mA charger for 2800 mA cells). Then I used the tool until the motor noticeably slowed, then I repeated the slow charge. After two trickle charges as explained, I used the tool like normal: Run until noticeably slower, but not dead- then use the factory charger. Each pack was used to depletion about 4 or 5 times on a project before the tool was put away.
Then, all good practice went out the window. I forgot about the tool, so it sat unused for 23 months. (I understand, maybe incorrectly, NiCAD cells get damaged if unused- whether charged or not.) Storage is basement temperature- About 75-F max and 35-F minimum.
After 23 months, I pulled out the tool and the motor sounded as fast as usual. So I immediately pulled the battery pack and tested voltage. For the 9.6 volt packs, I read 9.45 on one and 9.20 on the other. Since that day, I've used the packs on a project for two or 3 discharge cycles each. They perform quite well.
Searching on line about NiCAD self discharge only pulls up articles explaining how they do discharge while unused.
Is the NiCAD self discharge problem solved? Has the chemistry changed, or is the manufacturing procedure that changed? (Or nothing changed & I got a bunch of quirk cells.)
Also, is it OK to leave NiCAD sitting unused on a shelf, or should they be used & re-charged periodically?
Thanks for sharing!
Paul
I hope this note finds everyone well & enjoying today!
Almost two years ago, I installed new generic cells in a cordless screw gun's battery packs (9.6 volt NiCAD).
To equalize the cells in each pack, I first charged them as slowly as possible for about 16 hours (100 mA charger for 2800 mA cells). Then I used the tool until the motor noticeably slowed, then I repeated the slow charge. After two trickle charges as explained, I used the tool like normal: Run until noticeably slower, but not dead- then use the factory charger. Each pack was used to depletion about 4 or 5 times on a project before the tool was put away.
Then, all good practice went out the window. I forgot about the tool, so it sat unused for 23 months. (I understand, maybe incorrectly, NiCAD cells get damaged if unused- whether charged or not.) Storage is basement temperature- About 75-F max and 35-F minimum.
After 23 months, I pulled out the tool and the motor sounded as fast as usual. So I immediately pulled the battery pack and tested voltage. For the 9.6 volt packs, I read 9.45 on one and 9.20 on the other. Since that day, I've used the packs on a project for two or 3 discharge cycles each. They perform quite well.
Searching on line about NiCAD self discharge only pulls up articles explaining how they do discharge while unused.
Is the NiCAD self discharge problem solved? Has the chemistry changed, or is the manufacturing procedure that changed? (Or nothing changed & I got a bunch of quirk cells.)
Also, is it OK to leave NiCAD sitting unused on a shelf, or should they be used & re-charged periodically?
Thanks for sharing!
Paul