BATTERY PACK

An internal unit includes: a battery cell group including a plurality of battery cells; a holder holding the battery cell group; and a platform connected to the holder. The platform includes: an insulating major surface on which a positive electrode member and a negative electrode member are disposed adjacent to each other, the positive electrode member including a positive electrode-side circuit member or a terminal of a positive electrode-side electronic component, the negative electrode member including a negative electrode-side circuit member or a terminal of a negative electrode-side electronic component; and an insulating partition portion projecting from the major surface and separating the positive electrode member and the negative electrode member from each other.