Very simple NiMH Charger..

Hi!

So I wan't to create a simple 1/10 C charger for one of my power tools (a drill) and it is rated at 14.4V and 2200mAH so I should charge it at 220mAH then right?

Is it as simple as just using a 24V powersupply with 1 resistor to get the correct current?

And the resistor shuld be around 43 ohms (24-14.4/0.220)
AND I guess it must be able to handle >2Watts..

Are my calculations correct?

This is the very simplest form of charger, however, as the battery charges, the current will decrease.

I think there is a better solution on this datasheet:
https://www.electro-tech-online.com/custompdfs/2003/07/LM117PDF.pdf
(I refer to the "50mA Constant Current Battery Charger" on page 17).

Subsitute the 24 ohm resistor for 5.6 ohm (0.5W minimum). This should give you 223mA.

Thank you!

I'll give it a try....