Even after additional charging, the pack always seem to eventually settle back down to 16.45v total pack voltage.
So it seems 1.371v is their max charge capacity.
I also re-checked each cell and found each cell to measure 1.37v
Thanks to everyone for their help and advice. Great forum!
I think one thing I’ve learned is always check the batteries individually when I receive them BEFORE making a pack out of them.
Also learned a lot about testing batteries in a series pack.
Zebretta my curiosity is piqued. What is this pack for?
Is it for a handheld vacuum?
sounds like the pack is ok to me.
does it give the expected runtime?
Very good guess.
Hoover Impulse Cordless Power Mop
Yes. My wife likes to use it. No complaints from her over this. Seems to run as long as she needs it to.
I was just expecting a bit higher voltage. 12 x 1.2v (fully charged to 1.42v per cell I thought would be around 17.04v or so fully charged)
:+1:
I think these cleaning tools are the only things that take such a cell configuration and voltage.
Usually you will get the best battery longevity by unplugging the charger right after the light goes off. It seems if the battery lasts more than 18 months before starting to rapidly decline, you are lucky. I don’t know why Lithium cells are not standard in equipment like this. Maybe they don’t want the tool to last too long so they can sell you a new one every so often.
Did you build this pack yourself to replace one that failed? If so where did you get the cells?
Yes, I built the battery pack because we had a brand new one in storage but the battery was kaput.
The batteries were bought on ebay. (I know…bad place to get batteries)
I’ve never seen the green “full charge” light. I don’t think this battery pack reaches a high enough voltage to trip the green “full charge” light so I time it and then check the voltage.
Maybe they don’t use lithium cells due to the risk of fire?
ok thx. May try this soon.