The present invention suppresses a temperature rise of a battery cell due to a bus bar plate connected to first and second lead plates. In battery system in which a plurality of battery cells A included in battery block are connected in series as well as i...

A partition wall member includes a main body portion and a plurality of protrusions. The plurality of protrusions protrude from the main body portion toward at least one battery cell of the plurality of battery cells. Each of the plurality of protrusions h...