Help with a impact drill Li Ion battery.

[avz]

One more question, please. since I don't use the drill frequently, only once in a while (domestic use only, which I try to postpone) what is the recommended way to keep the battery? to keep it constantly connected to the charger? it might be weeks between one use to another.

 

[Diver300]

Lithium Ion batteries in good condition don't self-discharge much. However the battery management systems on some packs can discharge the battery a bit and it's difficult to know how fast the batteries will go down.

Once you have found out how fast they go down, you should recharge often enough to keep them from being completely flat.

It is best to keep them at no more than 80% charge if you can manage that.

 

[Tony Stewart]

21.58V would be the open circuit volt of the charger as the BMS is not allowing charge, no volt reading on the battery would be discharge is disabled as well due to some very low cells.


Better off getting a small bench supply, plenty of these on aliex too.

Like I said 21.58 or 4.3.. min per cell is too high for CV.
Add diodes to handle current and drop it 0.65 V.