A battery cell , comprising: a housing , comprising an opening; an electrode assembly , accommodated in the housing ; and an end cover assembly , comprising an end cover and an electrode terminal , the end cover being used for covering at the opening, the electrode terminal being installed on the end cover , and being used for electrical connection with the electrode assembly ; wherein, the end cover comprises a first body and a first convex portion , the first body comprises a first inner surface and a first outer surface arranged oppositely, and the first convex portion extends to a first end surface from the first inner surface along a direction facing the electrode assembly , a position on the first body corresponding to the first convex portion is formed with a first concave portion recessed from the first outer surface along the direction facing the electrode assembly , the first concave portion is configured to accommodate the electrode terminal , and the electrode terminal is located on a side of the first end surface away from the electrode assembly ; wherein the end cover assembly further comprises an insulating member ; the insulating member is located on a side of the end cover facing the electrode assembly , and the insulating member is used for separating the electrode assembly and the end cover ; wherein the insulating member comprises a second body and a second concave portion , the second body is located on a side of the first body facing the electrode assembly , the second body comprises a second inner surface and a second outer surface arranged oppositely, the second concave portion is recessed from the second outer surface along a direction facing the electrode assembly , and the second concave portion is configured to accommodate the first convex portion . a housing , comprising an opening; an electrode assembly , accommodated in the housing ; and an end cover assembly , comprising an end cover and an electrode terminal , the end cover being used for covering at the opening, the electrode terminal being installed on the end cover , and being used for electrical connection with the electrode assembly ; wherein, the end cover comprises a first body and a first convex portion , the first body comprises a first inner surface and a first outer surface arranged oppositely, and the first convex portion extends to a first end surface from the first inner surface along a direction facing the electrode assembly , a position on the first body corresponding to the first convex portion is formed with a first concave portion recessed from the first outer surface along the direction facing the electrode assembly , the first concave portion is configured to accommodate the electrode terminal , and the electrode terminal is located on a side of the first end surface away from the electrode assembly ; wherein the end cover assembly further comprises an insulating member ; the insulating member is located on a side of the end cover facing the electrode assembly , and the insulating member is used for separating the electrode assembly and the end cover ; wherein the insulating member comprises a second body and a second concave portion , the second body is located on a side of the first body facing the electrode assembly , the second body comprises a second inner surface and a second outer surface arranged oppositely, the second concave portion is recessed from the second outer surface along a direction facing the electrode assembly , and the second concave portion is configured to accommodate the first convex portion . <EOS>