A connector assembly comprising: a connector portion having an insertion port; and a bus bar portion having a bus bar, wherein the bus bar includes a first connection part extending in a first direction, a second connection part extending in an opposite direction from the first connection part along the first direction, the second connection part being inserted in the insertion port, and a joint portion joining the first connection part and the second connection part, wherein each of the first connection part and the second connection part has a thickness in a second direction intersecting the first direction, wherein each of the first connection part, the second connection part and the joint portion has a width in a third direction intersecting the first direction and the second direction, wherein the width of the joint portion is larger than that of each of the first connection part and the second connection part in a range from one end of the joint portion on a side adjacent to the first connection part to another end of the joint portion on a side adjacent to the second connection part, wherein a distance from the one end to the another end of the joint portion is larger than the width of each of the first connection part and the second connection part, wherein the bus bar includes a first bus bar and a second bus bar, wherein each of the first bus bar and the second bus bar has the first connection part, the second connection part and the joint portion, wherein the joint portion of the second bus bar extends longer in the third direction than the joint portion of the first bus bar, wherein the distance from the one end to the another end of the joint portion is larger than the width of each of the first connection part and the second connection part, wherein the joint portion of the first bus bar includes: an adjacent portion which is adjacent to and intersects the first connection part; and an extending portion which is bent from the adjacent portion and extends toward a side on which the second connection part is situated, wherein in the first bus bar, a width of the adjacent portion is larger than that of each of the first connection part and the second connection part, and wherein the width of the extending portion is equal to or smaller than that of the adjacent portion, characterised in that in the first bus bar, the width of the joint portion is larger than that of each of the first connection part and the second connection part in a range from the one end to the another end of the joint portion, and in that in the first bus bar, a width of the extending portion is larger than that of each of the first connection part and the second connection part. a connector portion having an insertion port; and a bus bar portion having a bus bar, wherein the bus bar includes a first connection part extending in a first direction, a second connection part extending in an opposite direction from the first connection part along the first direction, the second connection part being inserted in the insertion port, and a joint portion joining the first connection part and the second connection part, wherein each of the first connection part and the second connection part has a thickness in a second direction intersecting the first direction, wherein each of the first connection part, the second connection part and the joint portion has a width in a third direction intersecting the first direction and the second direction, wherein the width of the joint portion is larger than that of each of the first connection part and the second connection part in a range from one end of the joint portion on a side adjacent to the first connection part to another end of the joint portion on a side adjacent to the second connection part, wherein a distance from the one end to the another end of the joint portion is larger than the width of each of the first connection part and the second connection part, wherein the bus bar includes a first bus bar and a second bus bar, wherein each of the first bus bar and the second bus bar has the first connection part, the second connection part and the joint portion, wherein the joint portion of the second bus bar extends longer in the third direction than the joint portion of the first bus bar, wherein the distance from the one end to the another end of the joint portion is larger than the width of each of the first connection part and the second connection part, wherein the joint portion of the first bus bar includes: an adjacent portion which is adjacent to and intersects the first connection part; and an extending portion which is bent from the adjacent portion and extends toward a side on which the second connection part is situated, wherein in the first bus bar, a width of the adjacent portion is larger than that of each of the first connection part and the second connection part, and wherein the width of the extending portion is equal to or smaller than that of the adjacent portion, characterised in that in the first bus bar, the width of the joint portion is larger than that of each of the first connection part and the second connection part in a range from the one end to the another end of the joint portion, and in that in the first bus bar, a width of the extending portion is larger than that of each of the first connection part and the second connection part.