Patent ID: 8758919

Claim:
A battery pack for a power tool, comprising: a case main body configured to have an upper opening; a cover capable of closing the upper opening of the case main body; a plural number of rechargeable batteries stored inside the case main body; an internal case covering upper surfaces of the rechargeable batteries; charge and discharge terminals capable of connecting the rechargeable batteries to a power tool or a battery charger; a control unit capable of monitoring charge and discharge states of the rechargeable batteries based on signals transmitted from the rechargeable batteries; a plural number of signal lines capable of transmitting the signals from the rechargeable batteries to the control unit; a single band-like flexible base plate including a base plate main body having at least one bending portion bent by an angle of about 180 degrees, the flexible base plate being positioned on the internal case, and viewable when the cover is opened; a flat surface for placing the flexible base plate is formed on the internal case; a positioning protrusion is formed on the flat surface; and at least a pair of restraining protrusions being formed on opposite sides of the flat surface with respect to a widthwise direction of the flat surface, wherein the plural number of signal lines are formed on or within the single band-like flexible base plate.