To balance or not (LiPo)?

[mare69]

Hi!

I hope this is not too off-topic. It's related to powering LED with battery.

I am "permanently" developing some LED lights for biking. Recently I made own LiPo 2S pack with SII protection IC and industrial 4500mAh LiPo cells (2C discharge). I would like to know if balancing is required with LiPo cells when charging or not (for 2S pack)? The protection circuit will switch off in any case if one cell is overvoltage and other undervoltage, but this is extreme disbalance condition.

Thanks!
Marko

 

[DM51]

Welcome to CPF, mare69.

I think your question will do better in the Batteries section than H&M, so I'll move it there for you.

 

[ahorton]

You don't have to balance them, but I would. I know it seems extra effort, but you'll get better runtimes and be nicer to your cells, especially since you're pulling 2C out of them. Or maybe just balance them every few charges.

 

[Fitsbain]

Comming from the RC airplane world, I have found that if you charge slowly they will be balanced ok.

If you fast charge then balancing will become more necessary.

 

[Fallingwater]

From my days on the rcgroups board, I remember the advice given to people who asked this question was "balancing is very necessary for 3s+ packs, but you can do without with a 2s, although it wouldn't do any harm to do it anyway".

 

[mare69]

Thanks for the tips. I'll redesign the charger anyway. I have cypress PSoC for control of LED and charging, but at the moment without balancing. I could add balancing feature to be more safe with the 2S pack driving triple SSC P4.

Mare

 

[LuxLuthor]

Hi!

I hope this is not too off-topic. It's related to powering LED with battery.

I am "permanently" developing some LED lights for biking. Recently I made own LiPo 2S pack with SII protection IC and industrial 4500mAh LiPo cells (2C discharge). I would like to know if balancing is required with LiPo cells when charging or not (for 2S pack)? The protection circuit will switch off in any case if one cell is overvoltage and other undervoltage, but this is extreme disbalance condition.

Thanks!
Marko

Since you are apparently using LiPo from your link, I would absolutely recommend using balance charging taps.