Battery pack and charge equaliser

摘要

A battery pack 30 includes a charge equaliser to balance the charge across a plurality of cells 46 in the pack 30. The charge equaliser may monitor the battery voltages and discharge the cell 46 with the highest voltage until the charges of the cells 46 are balanced. The battery cells 46 may be arranged in two non-parallel sets to reduce the heat transfer between the cells 46. Data, such as battery chemistry, voltage, or temperature data, may be transferred between the battery cells 46 and a charger. Also claimed is a battery pack 30 for a power tool such as a drill or circular saw.