BATTERY PACK, ELECTRIC TOOL SYSTEM, AND CHARGING SYSTEM

Provided are a battery pack and a power tool and a charger applicable to the battery pack. The battery pack includes a housing of a first material, a cell assembly, and a cell support of a second material. The cell assembly is disposed in the housing and includes a plurality of cell units. The cell unit includes a positive electrode of the cell unit and a negative electrode of the cell unit. The cell support is configured to support at least the cell assembly. The cell support is at least disposed at two ends of the cell assembly, and at least part of the cell support encapsulates the positive electrode of the cell unit and the negative electrode of the cell unit. The first material is different from the second material.