A battery connection plate has a plurality of bus bars provided on a base plate section and is to be attached to a battery assembly containing a stacked plurality of batteries so that the bus bars are connected to terminals on the batteries. The base plate section has a wiring member attachment section to which a plurality of signal output wires connected to the bus bars can be wired, and window sections through which bosses can be inserted are formed on wiring paths of the signal output wires at the wiring member attachment section. The signal output wires are wired so as to bypass or wind around the bosses inserted into the window sections, and then the bosses are pulled out from the window sections, and thereby surplus length sections are formed on the signal output wires.