A battery pack, comprising: - an enclosure including an upper cover and a lower enclosure, wherein the upper cover is located above and in sealed connection with the lower enclosure; - a plurality of battery modules disposed inside the enclosure; and - a first bonding member disposed on an upper surface of the plurality of battery modules and for connecting the plurality of battery modules with the upper cover wherein - each of the plurality of battery modules includes a battery cell array comprising a plurality of battery cells arranged along a horizontal direction and a plurality of busbars electrically connected with the plurality of battery cells; - each of the plurality of battery cells includes an electrode assembly and a cell case, in which the electrode assembly is contained in the cell case and includes a first electrode plate, a second electrode plate, and a separator disposed therebetween; - the electrode assembly is of a flat wound configuration, and outer surfaces of the electrode assembly include two flat sides facing each other along a vertical direction; or the electrode assembly is of a laminated configuration, in which the first electrode plate, the separator and the second electrode plate are laminated along a vertical direction; and - the cell case includes two first surfaces and two second surfaces, wherein an area of each of the two first surfaces is larger than an area of each of the two second surfaces; the two second surfaces of each of the plurality of battery cells in the battery cell array face each other along the horizontal direction, and the two first surfaces of each of the plurality of battery cells in the battery cell array face each other along the vertical direction characterized in that - each of the plurality of battery modules further includes two straps arranged at an interval, each strap encompassing a periphery of the battery cell array and comprising two long sides and two short sides; the two long sides face to the two first surfaces and extend along the horizontal direction; and the two short sides face to the two second surfaces and extend along the vertical direction, and - a first groove is formed between two adjacent long sides above one of the two first surfaces facing the upper cover, and the first bonding member is disposed inside the first groove and extends along the horizontal direction. - an enclosure including an upper cover and a lower enclosure, wherein the upper cover is located above and in sealed connection with the lower enclosure; - a plurality of battery modules disposed inside the enclosure; and - a first bonding member disposed on an upper surface of the plurality of battery modules and for connecting the plurality of battery modules with the upper cover - each of the plurality of battery modules includes a battery cell array comprising a plurality of battery cells arranged along a horizontal direction and a plurality of busbars electrically connected with the plurality of battery cells; - each of the plurality of battery cells includes an electrode assembly and a cell case, in which the electrode assembly is contained in the cell case and includes a first electrode plate, a second electrode plate, and a separator disposed therebetween; - the electrode assembly is of a flat wound configuration, and outer surfaces of the electrode assembly include two flat sides facing each other along a vertical direction; or the electrode assembly is of a laminated configuration, in which the first electrode plate, the separator and the second electrode plate are laminated along a vertical direction; and - the cell case includes two first surfaces and two second surfaces, wherein an area of each of the two first surfaces is larger than an area of each of the two second surfaces; the two second surfaces of each of the plurality of battery cells in the battery cell array face each other along the horizontal direction, and the two first surfaces of each of the plurality of battery cells in the battery cell array face each other along the vertical direction - each of the plurality of battery modules further includes two straps arranged at an interval, each strap encompassing a periphery of the battery cell array and comprising two long sides and two short sides; the two long sides face to the two first surfaces and extend along the horizontal direction; and the two short sides face to the two second surfaces and extend along the vertical direction, and - a first groove is formed between two adjacent long sides above one of the two first surfaces facing the upper cover, and the first bonding member is disposed inside the first groove and extends along the horizontal direction.