Hello folks,

I need help designing a 15 cell LiFePO4 Battery Charging System. I have no idea where to start. I've seen designs for 2-4 cell systems, is there a way I can expand those designs to operate on 15 cells in series? The cells are 3.2V nom with 100A/H. Ideally I'd like the charger to be a 2A charger.

This is a link to the type of cell.

http://www.ev-power.eu/Winston-40Ah-200Ah/WB-LYP100AHA-LiFeYPO4-3-2V-100Ah.html

 

Are you planning to make only one of these, or do plan to sell some?

 

Making only one of these for a prototype design on a personal project.

 

Well I recommend that you try doing two or four cells at a time before you tackle 15. As I understand the literature they want you to charge them individually.

 

Seems like you should be able to do it.
You will need a 55 volt power supply with current limit and 15 balance modules.

 

I believe charging individually is for only the first charge. The statement on firse charge to connect all cells in parallel bothers me. For a $ 2133 battery, can not afford many mistakes. I did not see a suggested charging current but suspect for 100 Ah that 20 A would be in range; 2 A a little slow? A second or third reading might be in order.

 

according to the datasheeet they recommend optimal charging at 50 amps, for 2 hours, your 2 amp will take 50 hours, so your going to need a 55V 50 amp psu.

 

one advantage of the lifpe04 batteries is that they dont need super critical charging systems. 4 cells in series can be used as a car battery, using the cars charging system with no modifications. other types of Li batteries can catch fire, explode, or other nasty things if charged wrong, just a little, but the life04 dont require specialized charging systems.

 

Thank you all for the responses. I think I'm going to start with charging 2 cells at a time with an active cell balancing system. If that works I'll see if I can expand it upwards incrementally.