A battery module, comprising: a plurality of batteries, arranged in a longitudinal direction; an end plate, comprising: a main body portion, located on one side of the plurality of batteries in the longitudinal direction; and an extension portion, formed on the main body portion and extending in the longitudinal direction away from the batteries; an output electrode connecting sheet, comprising: a first connecting portion, connected to a corresponding battery; and a second connecting portion, connected to one end of the first connecting portion and fixed to the extension portion of the end plate; wherein the second connecting portion extends downward in an vertical direction and is located on an outer side of the extension portion in the longitudinal direction; wherein the second connecting portion of the output electrode connecting sheet is fixed to the extension portion of the end plate through a fastening assembly; wherein the fastening assembly comprises: a connecting member; and a mating member, mated with the connecting member to fix the second connecting portion of the output electrode connecting sheet to the extension portion of the end plate; wherein the battery module further comprises: a current collecting plate, fixedly connected to the second connecting portion of the output electrode connecting sheet through the fastening assembly; wherein the extension portion is provided with a restraint groove; and the connecting member is a hexagon head bolt, the mating member is a nut, a head of the connecting member is fixed in the restraint groove, and a tail of the connecting member protrudes from the second connecting portion of the output electrode connecting sheet to be fixedly connected to the mating member, the inner peripheral face of the restraint groove is formed into a hexagon head shape, the restraint groove is configured to restrain rotation of the head of the connecting member in an axial direction of the connecting member. a plurality of batteries, arranged in a longitudinal direction; an end plate, comprising: a main body portion, located on one side of the plurality of batteries in the longitudinal direction; and an extension portion, formed on the main body portion and extending in the longitudinal direction away from the batteries; an output electrode connecting sheet, comprising: a first connecting portion, connected to a corresponding battery; and a second connecting portion, connected to one end of the first connecting portion and fixed to the extension portion of the end plate; wherein the second connecting portion extends downward in an vertical direction and is located on an outer side of the extension portion in the longitudinal direction; wherein the second connecting portion of the output electrode connecting sheet is fixed to the extension portion of the end plate through a fastening assembly; wherein the fastening assembly comprises: a connecting member; and a mating member, mated with the connecting member to fix the second connecting portion of the output electrode connecting sheet to the extension portion of the end plate; wherein the battery module further comprises: a current collecting plate, fixedly connected to the second connecting portion of the output electrode connecting sheet through the fastening assembly; wherein the extension portion is provided with a restraint groove; and the connecting member is a hexagon head bolt, the mating member is a nut, a head of the connecting member is fixed in the restraint groove, and a tail of the connecting member protrudes from the second connecting portion of the output electrode connecting sheet to be fixedly connected to the mating member, the inner peripheral face of the restraint groove is formed into a hexagon head shape, the restraint groove is configured to restrain rotation of the head of the connecting member in an axial direction of the connecting member.