Battery pack enclosure

A battery pack comprising:

• a plurality of battery cells arranged in tiers;
• and
• a battery pack enclosure, wherein the battery pack enclosure comprises:
• a top panel;
• a bottom panel;
• and
• a plurality of surround frames, each surround frame supporting a tier of battery cells,
• wherein the surround frames are stacked, and
• a seal is provided between two adjacent surround frames.

A method of assembling an enclosure for a battery pack, the method comprising:

• providing a plurality of surround frames;
• supporting a plurality of battery cells on each surround frame;
• applying a seal to at least one surround frame;
• stacking one surround frame on another surround frame;
• and
• using a plurality of fasteners to apply a force to the surround frames, thereby applying a pressure to the seal.