Any suggestion for handling the current and the voltage here?

Community General Discussions
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I'm making a power board for my robot and I am looking for some advice regarding LiPo battery protection ICs.

I might need to draw a fair bit of current (9A), though if I get the programming right, it shouldn't be a problem (will probably be around 3A max).

Anyway, I was looking at using DS2764 from Maxim (datasheet:http://www.kynix.com/uploadfiles/pdf0125/DS2764AE2b025_67271.pdf), and it seems nice aside from the fact that I don't think I can use the 14.7V packs (need 12V output) I wanted to get :) Plus the current is limited to 2.5A. It also has the 2-Wire Interface that I don't plan using, so it's a bit of a waste.

Next, I started looking on Digikey for some LiPo protection devices, and now I'm confused: let's say I have a 14.7V LiPo battery, which means it's 4S I think. So technically there are 4 cells in there, but I don't have access to all 4. So when sorting the ICs, should I look for ones that say 1 cell (because that's the number of connections I have) or 4 cell? The 4 cell ones seem to always want inputs from all 4 cells...

Do you have any suggestions for something that can handle the current (I'm using a fuse anyways, so just as long as it has a fairly high limit it's probably ok) and the voltage? I know it's quite vague, but I don't really know where to look.

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Batteries

One cell = 1S = 3.7V. Therefore 14.8V / 3.7V = 4S. Hope that helps. If you need 12V, you should choose a 3S (11.1V). Most Lithium based batteries can handle fairly high current. You can check the maximum continuous discharge rate which is normally provided as a ‘C’ rating. For example if your battery’s capacity is 2,000mAh, and the maximum continuous discharge is 5C, then it can discharge at 5x 2A = 10A. 

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On LiPo batteries you have

On LiPo batteries you have when their bigger than 1S one connector for all small cells in series (so 4S --> 14.8V) and one connector with more cables that have usually a smaller diameter. This connector is used forcharging since you can charge each cell individually, which is important since LiPo batteries will be distroyed by a too high voltage. That’s why you charge them with this connector and discharge them with the one that has one lead and the higher voltage.

I don’t know any multi cell chargers/protection ICs though.

I hope that helps,

opidopi