# Batteries in parallel and amps?

Hello, I have a robot that requires approximately 10 amps. I have a maestro mini 24 channel servo controller and will be powering 12 servos that will have a fair amount of load on them. I have a voltage regulator that steps down the voltage to 3.3 or 5v, but it can only supply up to 7A. My question is, can I get two 5000 mAh betteries and plug each into a separate 5v regulator (so each gets the full 5000mAh instead of being limited at 7000mA) and then plug the two voltage regulators into the servo controller?

will this successfully bump up the amps to 10A and keep the voltage down to 5v?

thanks,
Brian

Hello.

You’re all over the place there. You should start with making sure you’re clear on the difference between A and Ah:

pololu.com/blog/2/understand … h-is-not-a

Most immediately, if you’re using batteries just for this, anyway, why are you using the regulators at all? You should just get a 4.8 V or 6V battery pack that has the capacity you need; anything around the 5Ah you are talking about will likely be able to deliver 10A.

- Jan

I am using the regulator because I was hoping to use LiPo batteries and I can’t seem to find any 3000-5000 mAh batteries in 4.8-6v. I figured I would just buy a 7.4 or 11v battery and use a voltage regulator.

Any suggestions?

also, did you mean just get 1 5000 mAh battery to supply 10A? or two in parallel? Just to make sure I understand correctly, either would work, right? the 5000 mAh would provide 10A constant for 30 minutes while the 2 5000 mAh batteries would provide 10A for 1 hour? (although I hear putting lipo batteries in parallel is dangerous).

One last thing, as size is an issue, I’m considering using 3 smaller 6v nimh 2000mAh batteries in parallel for a total of 6000mAh. Is it correct that if I set it up like this I will potentially get 30 minutes of 12A?

thanks again for all your help,
-Brian

So i’ve decided to go with the 3 2000mAh nimh batteries for my robot. I figure that I wont be using more than 10A at any given time, and will probably be averaging 5A for the most part. Anyways, I’m about to order my batteries but I have a question about charging in parallel. First of all, is this safe? I’d ideally like to charge all three batteries at once, and it would be the most convenient if I only have to plug in cord to charge (vs 3 individual ones).

So I’d like to hook these up in parallel when in use, and I’d also like to charge them while still in parallel (if possible).
any suggestions?

also, should I look into balancing chargers?

thanks,
Brian

I do not recommend putting batteries in parallel, for normal use or for charging (unless you really know what you’re doing, in which case you wouldn’t be asking these questions). If you need more capacity, get bigger batteries to begin with.

I have not seen balancing chargers for NiMH packs.

- Jan