An electrolyte includes a fluorinated cyclic carbonate, a chain carboxylate and a multi-nitrilemulti-nitrile compound having an ether bond. Based on a total weight of the electrolyte, a weight percentage (Cf) of the fluorinated cyclic carbonate is greater than a weight percentage (Cn) of the multi-nitrilemulti-nitrile compound having an ether bond. The electrolyte can control the expansion of the electrochemical device, so that the electrochemical device has excellent cycle, storage and/or floating-charge performance.