BATTERY PACK

The battery pack includes cylindrical battery and battery holder configured to dispose cylindrical battery in the predetermined position. Battery holder includes holding tube configured to internally accommodate cylindrical battery and cover outer circumferential face of cylindrical battery. Holding tube includes exposure window opened to allow outer circumferential face of accommodated cylindrical battery to be exposed therefrom to the outside. An exposed part of cylindrical battery exposed from exposure window is fixed to battery holder via adhesive member.