Batteries Charging Multiple 1-cell Lipos

mooserider

Active Member
Sorry if this is a newbie question... really I've search google, and even talked to a guy at the hobby shop today, and I still don't feel like I get it. Please keep in mind that I'm new to electrics (lipos). NiCads were much simpler.

I understand enough about multi-cells and my charger to not blow them up (which is minimal knowledge). Here's my formula... for example, my 3 cell batteries for the trex are 2200 mAh, 11.1v, 30c. They are advertised that you can charge them at double rate. So I set the charger to charge at 4.4a, 3 cell, 11.1v So 1x charge rate is 2.2a, double is 4.4a. I should mention that I'm using a 'balance board', where you plug in one four-pin (for 3-cell) to the board, and the dean's connector to the black/red power.

So for 1-cell batteries, used in the micro blade helis, I bought another board that has 8 slots. It does NOT plug into the balance board. It plugs into just the black/red output. These batteries are only 200 mAh, and 3v (?). So this is what I have been doing, but after talking to the hobby store guy, I may be doing it wrong. If I have 2 of the 2-cell, 200 mAh batteries plugged in, I would set the charger to 0.4a (400 mAh). 3 of them, set it to 600 mAh. Etc. That would be for a 1x charge rate. However, the guy at the store said to use 200 mAh charge rate regardless of how many batteries I have plugged in. Hope this makes sense.


Another question... the charger has all kinds of settings for all kinds of batteries (not just lipo, but NiMh and others). And for each type (in this case lipo), it has charge, balance, fast charge, and others. I've been using 'charge'... but am I supposed to use 'balance' because of the 'balance board'? Or is 'balance' for something else. The directions are written for someone with an electrical engineering degree.

Also, I do understand that charging more than 1x will shorten the battery life. But for the sake of my understanding of this stuff, I wanted to include it (and I do charge at 2x at least half the time... hell if it's a nice day in Seattle, it's worth it!)

Thanks all!

PS. 3s = 3 cell... why 3s and not 3c?

- - - Updated - - -

Correction for above (why can't we edit?)

This: "If I have 2 of the 2-cell, 200 mAh batteries plugged in"

Should read: "If I have 2 of the 1-cell, 200 mAh batteries plugged in"

1-cell batteries are what I'm talking about.
 

Lee

Well-Known Member
For parallel charging batteries, you just add up the mahs to give you the 1C charge rate.
So you're right with the one cell batteries, the more you plug in, just add up the Mah.
I would only charge the 1cell batteries at 1C.
Just make sure its a parallel charge board and not a series charge board.
On those you add up the voltage and leave the Mah the same.

Charge/ is for charging batteries without a balance lead (or in my case, when a battery balance lead is broken :) )
Balance charge/ is the norm for most of us. You plug in your balance leads to the balance board, and the charger keeps the charge even for all internal cells.
Fast charge/ allows the battery to charge more quickly, because it doesn't spend so long trying to get the battery perfectly balanced at the end of a charge.

When I'm out at the field I charge at the highest C rate allowable by my batteries, so I can get as many flights as possible.
At home when I know i'm not going flying again, I charge at 1 or 2C max as I'm in no hurry, and it doesn't reduce the battery life any more than necessary.

Hope this helps. :)
 

Tony

Staff member
Yup, no matter if it's 1s, 2s, up to 6s, the procedure is the same. On 1s, there is no balance charge since there is nothing to balance. Below is a video on how to parallel charge safely. Have a watch because you have to be careful of the voltages of each pack when you plug them in together.

Parallel Charging Lipo Batteries Safely - YouTube
 
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