Choose a compact battery protection board for your DIY Li-ion battery pack. Available in 3S and 4S configurations, with Balance and Enhance options.
Choose your board
3S 40A: Balance or Enhance version.
3S 60A: Balance or Enhance version.
4S 40A: Balance or Enhance version.
The 40A and 60A labels are supplier ratings. Suitable operating current depends on the selected board, battery cells, wiring and cooling.
Compatibility & contents
For compatible Li-ion cells rated at 3.7V nominal and 4.2V fully charged, including suitable 18650 cells.
Select the series count and version that match your battery-pack design.
Battery protection board only. Battery cells and charger are not included.
40A board dimensions
3S Balance: 41 × 61 × 4 mm
3S Enhance: 41 × 55 × 4 mm
4S Balance: 45 × 60 × 4 mm
4S Enhance: 44 × 55 × 4 mm
Dimensions are supplier-specified for the 40A versions. Check the selected variant before ordering; these dimensions do not specify the 60A boards.
Before installation
This is a protection board, not a standalone charger. Use a charger matched to your battery chemistry and series count. Follow the wiring diagram for the exact board variant, verify polarity and connections, and avoid short circuits. Battery-pack assembly requires suitable technical knowledge.
