Sealed battery, battery module, and method of manufacturing battery module

A battery module comprising:

• a plurality of sealed batteries each comprising:
• a battery case including at least one terminal mounting hole;
• an internal terminal disposed inside the battery case, and including a shaft portion inserted through the terminal mounting hole;
• an external terminal disposed on an outside of the battery case, and including an insertion hole through which the shaft portion of the internal terminal is inserted;
• and
• at least one insulating member interposed between the battery case and the internal terminal and between the batter case and the external terminal, the insulating member electrically insulating the battery case from the internal terminal and the external terminal, wherein:
• the shaft portion of the internal terminal is fastened to the insertion hole of the external terminal, and the shaft portion of the internal terminal is in direct contact with the insertion hole of the external terminal;
• and
• the external terminal includes a raised portion provided around a portion of the external terminal onto which the shaft portion of the internal terminal is fastened,
• wherein the external terminal includes a flat plate portion extending along the battery case in a direction away from the raised portion and the shaft portion, so that the raised portion is located between the shaft portion and the flat plate portion, and the insulating member is interposed between the external terminal and the battery case, wherein:
• the plurality of sealed batteries are arranged so that, in adjacent ones of the sealed batteries, the flat plate portions of the external terminals are aligned with each other,
• a bus bar is placed to span between the flat plate portions of the adjacent ones of the sealed batteries;
• and
• the bus bar is welded to the flat plate portions.

A method of manufacturing a battery module, comprising the steps of;

• preparing a plurality of sealed batteries, each of the plurality of sealed batteries comprising:
• a battery case including at least one terminal mounting hole;
• an internal terminal disposed inside the battery case, and including a shaft portion inserted through the terminal mounting hole;
• an external terminal disposed on an outside of the battery case, and including an insertion hole through which the shaft portion of the internal terminal is inserted;
• and at least one insulating member interposed between the battery case and the internal terminal and between the battery case and the external terminal, the insulating member electrically insulating the battery case from the internal terminal and the external terminal, wherein:
• the shaft portion of the internal terminal is fastened to the insertion hole of the external terminal, and the shaft portion of the internal terminal is in direct contact with the insertion hole of the external terminal;
• and the external terminal includes a raised portion provided around a portion of the external terminal onto which the shaft portion of the internal terminal is fastened, and a flat plate portion on an exposed surface of the external terminal, extending along the battery case from the raised portion with the insulating member interposed between the external terminal and the battery case wherein the raised portion is located between the shaft portion and the flat plate portion;
• arranging the plurality of sealed batteries side by side;
• and
• attaching a bus bar to the external terminals of adjacent ones of the plurality of sealed batteries, wherein:
• the step of arranging includes arranging the plurality of sealed batteries side by side so that, in the adjacent ones of the sealed batteries, the flat plate portions of the external terminals are aligned with each other, and
• the step of attaching a bus bar includes welding the bus bar, placed to span between the flat plate portions of the adjacent ones of the sealed batteries, to the flat plate portions.