Hi,

I'm trying to find out the remaining charging cyles on NiMH AA 1.2V rechargable batteries.

I'm placing a battery in series with a the parallel of 3 resistors of 2.2 ohms which are 5, 10 and 20 watts respectively.
To log the discharge and using an Arduino UNO and with some visual basic code i can see on every second, the voltage values measured (it also shows a graph).

When checking a functional battery it takes 15327 seconds before the curve shows it's discharge and it takes 9000 seconds on the non functional.

I would like to know what parameters i should take into account to know the remaining charging cycles.

Regards,

 

Even the manufacturer doesn't know.
In addition, useful cycles remaining depend on the job the cells are used for. When you get done deciding how well they work heating your resistors, I have a Makita 9.6V drill from 1988 you still won't be able to predict.

The only clue I have is that lead acid batteries can be estimated by measuring their conductivity. That test reveals how much surface area has been destroyed. I don't think that method applies to Ni-Cad batteries, but you're welcome to find out.

 

Thanks for replying.
As you mention it, i don´t think that method will can bi applied on these NiMH batteries, i'll keep searching.

Regards,