DenCo™ - Can you believe it?

This was my first build using LiitoKala “7Ah” LiFePO4 cells from AliExpress. The rating seemed too good to be true, and in actuality these cells go about 6 amp-hours. Like the Mk II, this battery incorporates the 100A BMS and an automotive fuse.

General Specs:
Created: June 14, 2019.
Cells: LiitoKala 32700 7Ah 3.2v LiFePO4
BMS: HX-4S-F100A
Configuration: 4S2P
New since last make: New cells to try, automotive fuse 25A.
Current Owner: K4WDY Woody

Cell specs:
LiitoKala 32700 cells
Nominal Capacity: 7Ah (6.5Ah in practical use)
Nominal Voltage: 3.2V per cell
Dimensions: 32mm x 70 mm
Weight: 145g per cell
Internal resistance: less than 8 mΩ
Cycle life: > 2000 cycles, DOD at 80%
Input charging voltage: 3.65v/cell
Input charging current: 3A
Continuous discharge current: 30A
Max discharge current (pulse): 6C
Discharge cut-off voltage: 2.5V
Charging temp: 0-45°C
Discharge temp: -20°C – 60°C
Storage temp: -20°C – 45°C

BMS Specs:
HX-4S-F100A BMS
1. Continuous discharge current: 100A
2. Instantaneous discharge current: 120A
3. Charging Voltage: Iron lithium charger 14.8V (Switching power supply: 15V-16V)
4. Charging Current: 10A(Max)
5. Overcharge detection voltage: 3.75V±0.05V
6. Over charge detection delay time: 1300 ms
7. Over charge release voltage: 3.6V±0.05V
8. Electricity equalization detection voltage: 3.6V±0.05V
9. Electricity equalization release voltage: 3.59V±0.05V
10. Electricity equalization current: 58mA
11. Over discharge detection voltage: 2.1V±0.08V
12. Over discharge detection delay time: 145s
13. Over discharge release voltage: 2.30V±0.1V
14. Over current detection voltage: 200mV
15. Over current detection delay time: 20mS
16. Over current protection current: 120V±10A
17. Over current protection release: Cut off the load
18. Detection condition: Exterior load short circuit
19. Detection delay time: 300us
20. Over current protection: Cut off the load
21. Temperature Protection: Can use an external temperature switch
22. Main circuit conduction resistance ~20mΩ
23. Working current: ~30uA
24. Working Temperature: -20°C to 80°C
25. Size: 70 x 60 x 8.5mm