Abstract: A battery pack has bus bars, a battery stack which is an assembly of plural battery cells, a bus bar casing which supports a bus bar casing, and a cover member. Electrode terminals of battery cells adjacently arranged in the battery stack are connected together through the bus bars. An upstream side passage and a downstream side passage are formed between the bus bars and the cover member. Upstream side wall surfaces forming an inlet part of the upstream side passage or downstream side wall surfaces forming an outlet part of the downstream side passage is arranged at a location closer to the battery cell side than a location of a surface of the bus bar side.

Abstract: Each battery module of a battery pack includes a stack of serially connected battery cells, a gas discharge duct extending in a cell arrangement direction to guide gas discharged from a relief valve of each battery cell to an outside of the battery module, the gas discharge duct having a first connection opening at one end and a second connection opening at the other end, a first connection terminal piece having an inner end portion electrically connected to an electrode of one of the battery cells at one end of the serial connection and an outer end portion disposed inside the first connection opening, and a second connection terminal piece having an inner end portion electrically connected to an electrode of another one of the battery cells at another end of the serial connection and an outer end portion disposed inside the second connection opening.

Abstract: Each battery module of a battery pack includes a stack of serially connected battery cells, a gas discharge duct extending in a cell arrangement direction to guide gas discharged from a relief valve of each battery cell to an outside of the battery module, the gas discharge duct having a first connection opening at one end and a second connection opening at the other end, a first connection terminal piece having an inner end portion electrically connected to an electrode of one of the battery cells at one end of the serial connection and an outer end portion disposed inside the first connection opening, and a second connection terminal piece having an inner end portion electrically connected to an electrode of another one of the battery cells at another end of the serial connection and an outer end portion disposed inside the second connection opening.

Abstract: A battery pack has bus bars, a battery stack which is an assembly of plural battery cells, a bus bar casing which supports a bus bar casing, and a cover member. Electrode terminals of battery cells adjacently arranged in the battery stack are connected together through the bus bars. An upstream side passage and a downstream side passage are formed between the bus bars and the cover member. Upstream side wall surfaces forming an inlet part of the upstream side passage or downstream side wall surfaces forming an outlet part of the downstream side passage is arranged at a location closer to the battery cell side than a location of a surface of the bus bar side.