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Topic: 5V supply help needed (Read 4 times) previous topic - next topic

Jack Christensen


So I'm thinking in the first wave of searching, 8 of these should meet those requirements.  Hooked up in parallel should give me 24AH.
http://www.batteryjunction.com/ultrafire-brc-18650.html

I'm still looking for smaller or flatter, but those are a good first round pick i think.


I am certainly not an expert on Lithium batteries, but I think there are some considerations when connecting them in parallel. Note the comment on the cells above:

Quote
These fully protected cells simplify usage with their integrated PCB. Perfect for your single cell application these cells are not for pack building as doing so will defeat the PCB protection which is matched to the correct voltage on a single cell. If you are building a pack please choose one of our other cells and the appropriate PCB.
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

cyberhedz

DOH, i definitely missed that, well, at least I've found "pack friendly" 2.6AH in the same size.

cyberhedz

So just to make sure I'm understanding this, if I use something like this:
https://www.sparkfun.com/products/8483

and hook up say, 10 of them, in parallel, then a single charge circuit would be sufficient?  I'm also looking at several of the 18650 style batteries, quite a capacity to reach, I'm trying to get around 20AH at a minimum, but reaching the goal would be even better.

cyclegadget


Jack Christensen


So just to make sure I'm understanding this, if I use something like this:
https://www.sparkfun.com/products/8483

and hook up say, 10 of them, in parallel, then a single charge circuit would be sufficient?  I'm also looking at several of the 18650 style batteries, quite a capacity to reach, I'm trying to get around 20AH at a minimum, but reaching the goal would be even better.


Like the others, they may not be designed to be used in parallel. I took a quick spin through the datasheets, both for the battery and for the built-in protection circuit and didn't find them very enlightening. Unfortunately, like I said, I'm not a Lithium battery expert. Maybe someone else on the forum can chime in here. I'd be very careful to use them properly and charge them properly.
MCP79411/12 RTC ... "One Million Ohms" ATtiny kit ... available at http://www.tindie.com/stores/JChristensen/

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