PROBLEMS OF CORROSION AND OTHER ELECTROCHEMICAL SIDE PROCESSES IN LITHIUM CHEMICAL POWER SOURCES WITH NONAQUEOUS ELECTROLYTES

The following electrochemical side processes were studied: (i) electro chemical corrosion processes in a short-circuited couple of active cat hode material (FeS2)-current-collector material, and (ii) electrochemi cal and chemical decomposition of nonaqueous electrolytes proceeding i n parallel with the base electrochemical reaction in power sources wit h a working discharge voltage of 1.5 V. The dynamics and direction of corrosion processes in the couple of FeS2-current collector depend on the potential difference between the active cathode substance and the current-collector material and on the overvoltage value of conjugated electrochemical processes. In the case of a Starting unreduced cathode , the reduction process takes place on pyrite and the oxidation proces s occurs on the current collector. After a partial cathode reduction t he process direction changes. The rate of decomposition of the electro lyte in the potential range of 1.5 V is determined by its composition, the conditions of its. preparation and purification, and the cathode material used as catalyst in the process of the decomposition of the e lectrolyte.