SECONDARY BATTERY AND DEVICE INCLUDING THE SAME

The present application provides a secondary battery and a device comprising the same, the secondary battery comprising: a negative pole piece, the negative pole piece comprising a negative active material; the isolating membrane comprises a base material and a coating arranged on at least one surface of the base material; the electrolyte comprises an organic solvent; wherein the negative electrode active material comprises a silicon-based material and a carbon material; the thickness of the base material of the isolating membrane is 7-12 [mu] m; the organic solvent comprises ethylene carbonate, and the weight ratio of the ethylene carbonate in the organic solvent is less than or equal to 20%. According to the secondary battery and the device comprising the secondary battery, on the premise of high energy density, relatively good high-temperature cycle performance, relatively good high-temperature storage performance and relatively low low-temperature direct-current impedance can be taken into consideration at the same time.