The invention discloses a protection method of a
lithium metal electrode. By use of a simple alloyage method,
antimony trifluoride is utilized to form an artificial protective film on the surface of alithium
cathode, so that polarization of the
lithium cathode can be effectively lowered, and generation of dendritic crystals can be suppressed. According to the method,
antimony trifluoride and
lithium are mainly utilized for a reaction to generate the dense artificial protective film, wherein
antimony trifluoride is dissolved in
propylene carbonate to prepare a uniform solution first, pretreatment is performed on the surface of a lithium
wafer to remove oxidized lithium on the surface, the lithium
wafer is
cut into a round
wafer, the round wafer is immersed in the antimony trifluoride solution for a reaction to obtain a treated
lithium electrode, and finally a symmetric battery is obtained through assembling. Through a low-concentration long-
time reaction, a dense
alloy layer can be generated on the surface of
lithium metal. Through the method, the polarization of the
lithium metal cathode is fully lowered, circulation stability is good, generation of lithium dendritic crystals is effectively suppressed, and the stable
lithium metal cathode is obtained; and when the lithium
metal cathode is applied to a
lithium battery, the circulation performance and safety performance of the
lithium battery can be improved, and potential commercial application value is obtained.