Li-Ion Battery Pack 12s 44.4V With BMS

Li-Ion Cells are available in many sizes and capacities. However it is not easy to get a "ready-to-run" battery pack for the own project. I spent some time to design my own pack suitable for high power application, modular design to increase capacity with further packs.

My battery pack will consist of 12 cells in series connected to a BMS.

Main data:

44.4V

4.8Ah

50A cont. discharge rate (BMS limiting at 60A)

Step 1: ​Bill of Material

Li-Ion Cell - VBatty

Cell Holder

BMS - Deligreen

Hiluminband - 7mm x 0.3mm

Cable

Solder

Total costs: 75€

Step 2: Cell Holder

Cell holder are cheap and useful to set the right shape of battery pack.

Step 3:

Soldering the Hiluminband is quite easy. I put a little bit of solder on the battery cell, place the hiluminband on it and heat it - until it melt the solder.

Step 4: BMS Connector

The BMS is monitoring each cell voltage. The connector cable is included and it is just needed to solder it between the cells.

Step 5: Finish

Finally I added a XT90 connector and covered the battery pack with tape.

I build four of this battery packs and connect them in parallel to get one high capacity, high power battery pack.

With a 50.4V 10A power supply unit I can charge all packs at once.

Each BMS is limiting to 60A so I got 240A & 44.4V finally.

Compared to my previous LiPo this one is really comfortable when it comes to charging.