Battery pack with wire bonded bus bars

A method of forming a mobile power supply, the method comprising:

• forming a frame having a first support member and a second support member, each of the first and second support members being formed from a plastic material and including a plurality of cylindrical recesses arranged in vertical columns that receive the plurality of battery cells to support the battery cells and elongate recesses, each of the elongate recesses positioned adjacent to at least one column of the plurality of cylindrical recesses;
• positioning a bus bar within one of the elongate recesses of the first support member, each bus bar including an elongated conductive body having a base and fingers extending laterally away from the base, the base defining a recess extending along a longitudinal length of the base between at least two of the fingers, the fingers extending within a first plane and the base extending within a second plane that is parallel to the first plane and offset therefrom;
• injecting the recess of each of the bases with the plastic material such that the plastic material fills the recess and integrally forms with the first support member;
• positioning a plurality of battery cells between the first support member and the second support member such that the plurality of cylindrical recesses of the first support member and the second support member support the plurality of battery cells, each of the battery cells having a first end, a second end opposite the first end, a positive terminal located at the first end, and a negative terminal located at the first end;
• and
• wire bonding wires between the fingers each of the bus bars and either the positive terminal or the negative terminals.