Build your own 12.8 V 12 Ah LiFePO4 pack: 4S2P 32700 cells and a BMS
Open in the lab ▸Make my own copy
Make a 12.8 V battery yourself. Eight 32700 LiFePO4 cells (3.2 V, 6 Ah each) go in pairs: two in parallel make 6 Ah → 12 Ah, four pairs in series make 12.8 V. A 4S BMS watches every pair through its balance wires, stops the charge at 3.65 V a cell, cuts the load at 2.5 V and shorts. 154 Wh for a third of the price of a ready-made pack, and nickel strip instead of wires between the cells, as a spot welder would do it. A bulb and a battery meter show it working. Every part is on the bench, and Buy all the parts (on the project strip, or Menu → Make) lists them with an estimated price and shop links. Estimates are for the Philippines; check each listing before you buy.
What is on the bench
11 parts, 20 wires.
| LiFePO4 cell | 8 |
|---|---|
| 4S LiFePO4 BMS | 1 |
| 12 V DC LED bulb | 1 |
| Battery capacity indicator | 1 |
Put it on your page
The project runs live inside the frame: readers can press buttons, turn knobs and read the meters.
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Link
https://zencircuitlab.com/p/zclspack
Published by its author under the lab's community terms: it may be opened, copied and changed by anyone. Simulation results are for learning; check a real build against the parts' datasheets.