In System Battery Charge Monitoring

Good day all,

 

I appologize if this has been asked before but I am building a robot that is starting to have what I would consider a complex power system with three different Ni-MH batteries powering different systems. This section of the robot is controlled via and Arduino which talks to the main robot "Brain" a ARM Cortex-M3 processor. What I need to be able to do is check the charge level on these three cells so that the robot knows how much power is remaining.

I have googled alot trying to find a circut or tutorial, but either my google-fu is broken today or I am just not searching with the right words, I would greatly appreciate any help you guys can offer.

 

The Trusted One

I think maxim ic has stuff
I think maxim ic has stuff that can do that. check them out.

NiMH cells have a rather

NiMH cells have a rather flat voltage curve as they discharge which is great for powering stuff, but it makes it hard to get feedback as the voltage doesn’t change much as they expend energy. The voltage will also fluctuate around depending on loading, which can make getting an accurate reading tough when the cells are actively being used in a robot.

I’d check out Maxim’s products as voodoo suggested, but you could build your own using an ADC and some clever programming.