A terminal spacer having a cylindrical shape is attached to the circumference of an electric wire connected to a charge terminal. The terminal spacer includes a slit portion extending across the entire length in the axial direction of the terminal spacer. The slit portion includes an electric wire insertion slit portion into which the electric wire can be inserted, and a narrow slit portion continuously extending from the electric wire insertion slit portion and having an opening width narrower than that of the electric wire insertion slit portion.