LITHIUM ION SECONDARY BATTERY AND ELECTRIC VEHICLE

Provided is a lithium ion secondary battery, comprising a housing (1) and at least two cells (4) encapsulated in the housing (1). The housing (1) is provided with at least one cooling unit (2) extending along a length direction (L1) of the housing (1). The cooling unit (2) is provided with a coolant channel (21) for coolant circulation, the cooling unit (2) divides the internal space of the housing (1) into at least two accommodating cavities (12) spaced apart along a thickness direction (T1) of the housing (1). Each battery cell (4) is arranged in each accommodating cavity (12), and the cooling units (2) are in thermal conduction contact with the cells (4) in the adjacent accommodating cavities (12). By providing the cooling unit (2) in the housing (1), the heat generated by the battery cell (4) can be conducted in time, thereby quickly and effectively solving the heat dissipation problem of the battery cell (4) during charging and discharging. Also provided is an electric vehicle.