Electrolyte containing composite additive and battery containing electrolyte

• Main Authors: PENG CHUNYU, WANG HAI, ZHONG YAOTANG, LI XUXIAN
• Format: Patent
• Language: Chinese; English
• Published: 22.09.2023
• Subjects: BASIC ELECTRIC ELEMENTS; ELECTRICITY; PROCESSES OR MEANS, e.g. BATTERIES, FOR THE DIRECT CONVERSIONOF CHEMICAL INTO ELECTRICAL ENERGY

The invention provides an electrolyte containing a composite additive and a battery containing the electrolyte. The composite additive is prepared from 1, 4-dicyano-2-butene (DB) and fluoroethylene carbonate (FEC); after the DB and the FEC are combined to form a composite additive and the composite additive is added into the electrolyte, a CEI film and an SEI film with organic components and inorganic components, which are constructed by the DB and the FEC through a synergistic effect, are more stable and stronger in ion conductivity, so that surface structure collapse of a lithium cobalt oxide positive electrode and harmful side reaction of a positive electrode/electrolyte interface can be prevented, dissolution of cobalt is inhibited, and the service life of the electrolyte is prolonged. Therefore, the oxygenolysis of the electrolyte can be inhibited, the increase of electrode polarization can be weakened, and the cycling stability of the lithium cobalt oxide positive electrode under high voltage can be gre