BMS with 18 working cells of Samsung 40T 21700

10S2PS battery pack with Samsung 40T 21700 cells. Used for only 25 cycles before it stopped charging due to 1 group of the cells going bad. Works out to be less than $3 per cell (18 working cells total). Only a quarter of the new cell price, and you get a BMS with it. Tested each cell group; 9 out of 10 groups reads between 3.3-3.4v, with only one group that is nearly dead. Key specs for the Samsung 40T battery cell (model INR21700-40T): - Capacity: 4000mAh - Nominal Voltage: 3.6V - Full Charge Voltage: 4.2V - Discharge Cutoff Voltage: 2.5V - Continuous Discharge Rating: 35A (max) - Cell Size: 21700 (21.1mm diameter × 70.4mm length) - Weight: Approximately 67g - Cycle Life: Around 250–300 cycles to 60% capacity - Unprotected cell (requires proper battery management) - Operating Temperature: Charge 0–45°C, Discharge -20–60°C. The 40T is designed for high capacity and high power output, popular in electric vehicles and high-drain devices. Pickup from Ajax during weekdays. Can meet in Toronto on weekends.