Battery module with improved stability
A battery module which may prevent or delay a short circuit with respect to nail penetration includes a cell assembly including a plurality of cells electrically connected to each other, an outer case of the battery module, covering the cell assembly, and an elastic refractory part provided in a region between the outer case of the battery module and an outermost cell of the cell assembly or a region between one of the cells and an adjacent cell in the battery module, wherein the elastic refractory part includes an elastic layer and a heat conductive layer.
1 . A battery module, comprising:
a cell assembly including a plurality of cells electrically connected to each other;
an outer case of the battery module, covering the cell assembly; and
a plurality of elastic refractory parts provided in two regions between the outer case of the battery module and an outermost cell of the cell assembly, and a region between one of the cells and an adjacent cell in the battery module,
wherein the elastic refractory parts have a thickness of 30 μm to 5 mm and include an elastic layer and a heat conductive layer, wherein each of the elastic layer and the heat conductive layer has a thickness of 9 μm to 3 mm independently,
wherein, in the elastic refractory parts provided between the outer case of the battery module and the outermost battery cells of the cell assembly, each elastic layer is adjacent to and in direct physical contact with an outer surface of each of the outermost battery cells,
wherein the elastic layer has an elongation rate of 50% or higher,
wherein the battery module includes a cooling plate,
wherein the elastic refractory parts are connected to the cooling plate through a thermal adhesive,
wherein the elastic layer and the heat conductive layer are bonded by an adhesive layer, the adhesive layer has a shear strength of 300 kgf/in 2 or greater as measured by attaching the adhesive layer to an SUS substrate after removing a release paper at room temperature according to ASTM D5656,
wherein the adhesive layer includes a base film comprising at least one selected from the group consisting of PET, polyimide, fluoropolymer, and PVC, and an adhesive disposed on the base film and comprising at least one selected from the group consisting of acrylic, silicone, rubber, and epoxy, and
wherein the heat conductive layer has a heat transmission coefficient of 5×10 3 W/m 2 ·K to 5.5×10 7 W/m 2 ·K.
2 . The battery module of claim 1 , wherein the cell is a pouch-type lithium secondary battery.
3 . The battery module of claim 1 , wherein the elastic layer is formed of at least one selected from a group consisting of silicone, latex, polyurethane, and natural rubber.
4 . The battery module of claim 1 , wherein the heat conductive layer has a thermal conductivity of 0.5 to 500 W/m·K.
5 . The battery module of claim 1 , wherein the heat conductive layer includes graphite.