Connecting two batteries in parallel


I need technical support. I am looking to buy the Polymer Lithium Ion Battery (LiPo) 3.7V 2000mAh. I need 4000mAh, will I be able to just connect two of these batteries in parallel to get my desired capacity? I know this is possible but not sure about connecting the 2 PCMs together. Will I need to get rid of one of them?

Kind Regards,


Hi David,

Just use this battery, it’s a little higher capacity but that never hurts:

While you can connect two lipo batteries together, I strongly recommend that you dont. The cells must be equally charged at the time of connection, and you will need to disconnect them from each other and charge them separately. Connecting two single cell Lipo batteries in parallel, and then connecting to a device with battery charging capabilities will lead to unbalanced charging and that can cause a fire.

Hi Stephen,

Unfortunately, the size constrains of my project won’t let me use a thicker battery. I ordered the 4400mAh battery previously and it’s just 4 cells connected together to a protection circuit board (PCM). Can I do a similar technique to what you guys have done with this battery?


Hi David,

Once again I strongly discourage altering these batteries in any way. I won’t give any advice that requires it as it is very dangerous. Best of luck with your project!