l Only connect cells that are matched in capacity. Do not mix cells of different chemistries.
l Never charge or discharge Li-ion batteries unattended without a working protection circuit. Each cell must be monitored individually with a protection circuit.
l Include a temperature sensor that disrupts the charge current on high heat.
l Apply a slow charge to a repaired pack to bring all cells to parity.
l Pay attention when using an unknown brand. Elevated temperature hints to an anomaly.
l Li-ion is sensitive to reverse polarization. Observe correct polarity.
l Do not charge a Li-ion battery that has physical damage, has bulged or has dwelled at a voltage of less than 1.5V/cell for some time.
l Check a repaired pack for self-discharge. Intrinsic defects often have high self-discharge.