ELECTROLYTE AND ELECTROCHEMICAL DEVICE

An electrochemical device, including a positive electrode, a negative electrode, a separator and an electrolyte. The electrolyte includes a nitrile compound, and the mass percentage of the nitrile compound in the electrolyte is A %; the negative electrode includes a current collector, wherein the current collector comprises a first region and a second region; the first region is provided with a negative electrode active substance layer; the second region does not comprise a negative electrode active substance layer; the area of the second region is B % of the surface area of the current collector; and A×B