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How to safely connect more lipos

Hi guys,

I have 2 LiPo's and I want to spit out the united force of them into my circuit. Not sure if that is paralel or serial, and nor do I mind much, I want the verion that gives higher volts. But of course I am afraid of messing with LiPo's , so here you have my life in your hands. Will the below do?

Thanks.

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merser's picture

lipo packs without any regard than usual battery connections. I will let you know if they explode. Haha...

arbarnhart's picture

Yes, it just means they did it for you. But then recharging is easy also. This is a case where respect is better than fear but fear is better than no respect. If you carefully deal with one lead at a time you will be fine. You can treat them like other batteries as far as wiring goes. The same things work and the same things fail. The failures are just more spectacular...

fritsl's picture

Thanks.

Now that I have no 7.4, but two 3.7, I will have to manage :)

So you are saying that I can drop the diode, just dont short anything?!

arbarnhart's picture

They behave just like other batteries. They only misbehave differently. I have heard the bit about keeping them even also. It seems to be even more important when you have lots of cells. They will have this second connector just for a high end level charger. Another guy I am doing some work with has one of those and he charges the big scary batteries. 

birdmun's picture

I even did a quick search and found a guy that wanted to sell the connection you are making, minus the diode, for $12 shipped anywhere in the US. :P

I did read that you want to make sure when you use them in series like that, that you keep them in the same state of charge (don't run one down and then recharge it to use with the one that might be partially discharged).

JAX's picture

This site might be helpful for setting up a charging scheme...

http://scriptasylum.com/rc_speed/lipo.html

Balance chargers are pretty cheap and they keep the individual cells in your pack nice and happy. That link will show you how to wire them up.

http://www.dealextreme.com/details.dx/sku.20025

Just an example of a balance charger but there are many like it out there. Most of the cheap balance chargers come with alligator clips for a 12V battery source but they work fine with a 12V wall wart.

fritsl's picture

Brilliant, thanks birdmun!

:)

GranTotem's picture

These batteries dont really like being treated bad youre right... http://www.youtube.com/watch?v=-DcpANRFrI4

GranTotem's picture

Well I believe, from my knowledge about diodes, it would stop electricity flowing 2 ways and making it flow 1 way. So in theory you should be safe with it I´m not really sure about which way the black line should go...

And finally the reason being I put "LOL" as title is that I just learned how to by checking online... :D

birdmun's picture

I would avoid the diode as you will lose voltage. I can't imagine that there would be any problem just connecting in series w/o the diode.