A battery spacer includes: a storage case having a bottomed cylindrical shape in which a battery is stored; a lid part which closes an opening of the storage case; and a positive electrode relay terminal which is provided to the lid part, a part of which protrudes from a top surface of the lid part, and which abuts on a positive electrode terminal of the battery in the storage case. The lid part has a protruding section formed which protrudes further to the battery side than a terminal contact surface at which the positive electrode terminal of the battery abuts on the positive electrode relay terminal. The protruding section has a protruding length h, in the axial direction of the battery, from the terminal contact surface, shorter than the length H of the positive electrode terminal of the battery, and has an annular shape having a diameter R that is larger than the diameter r of the positive electrode terminal of the battery and is smaller than the diameter S of the battery in the radial direction of the battery.