Balance Charger

Multi-cell LiPo and LiFe packs drift out of balance over repeated cycles — one cell ends up slightly higher or lower voltage than its neighbours — and charging only through the main power leads would push a weak cell into overcharge while others lag behind.

A balance charger reads each cell through the pack's separate balance connector and trickles current individually so every cell finishes at the same voltage, which is both a safety requirement for lithium chemistries and the reason a pack's actual usable life stays consistent charge after charge. Charging any multi-cell LiPo without one is a real fire risk, not just a performance issue.

Most modern chargers display each individual cell's voltage during charging, and checking that display for one cell reading noticeably out of line with its neighbours is a quick way to catch a failing cell before it becomes a real problem.