Battery assembly and battery pack including battery assembly

A battery pack comprising:

• a plurality of battery assemblies;
• a pack housing structured to accommodate the plurality of battery assemblies;
• and
• an external busbar configured to electrically connect adjacent battery assemblies;
• wherein each of the plurality of battery assemblies comprises:
• a cell stack including a plurality of battery layers of battery cells, each battery layer including a plurality of battery cells arranged such that largest surfaces of the battery cells are oriented in a first direction, each battery layer comprising two or more third-direction battery rows each third-direction battery row including of the plurality of battery cells arranged in a third direction;
• and
• one or more busbars coupled to the plurality of battery cells and configured to electrically connect the plurality of battery cells,
• wherein the cell stack includes a first second-direction battery row and a second second-direction battery row in which the plurality of battery cells is arranged in a second direction,
• the first second-direction battery row includes first electrode terminals and the second second-direction battery row includes second electrode terminals disposed to be oriented in an opposite direction to the first electrode terminals based on a reference surface between the first second-direction battery row and the second second-direction battery row, and
• the one or more busbars include a transversal busbar configured to connect one or more of the first electrode terminals of the first second-direction battery row to one or more of the second electrode terminals of the second second-direction battery row and configured to traverse the reference surface.