Vintage Cordless Knife Cutter Restoration | HITACHI CK 12D

I found this tool from Japan recycling shop in my city. It is an old model cordless knife cutter made by Hitachi, Japan. The tool is working fine except for the battery. I convert the Nicd battery to a Li-ion battery. I use 6 cells of 18650 and BMS 3S40A to build a new Li-ion battery pack 6Ah. * BMS 3S40A is a battery management system for 12V battery pack 3S 40A 40A lithium battery protection board (comes with recovery function-AUTO Recovery) Scope: Nominal voltage of , lithium battery (including 18650,26650, polymer lithium battery) Charging voltage: - Continuous discharge current (upper limit): 40A (if the cooling environment is not good, please reduce the load current use) Continuous charge current (upper limit): 20A * Lithium-ion battery cell - Brand model: LG INR18650HG2 - Standard capacity: 2800- 3000mAh - Rated voltage: - Charging voltage: 4.2± - Maximum continuous discharge current: 20A - Discharge cut-off vol