INFLUENCE OF THE COMPOSITION OF LITHIUM-BASED ALLOYS, NONAQUEOUS ELECTROLYTES AND CYCLING CONDITIONS ON THE ANODE PROPERTIES

The reversible work of a lithium-based anode in non-aqueous electrolyt es of different compositions has been investigated. The electrochemica l properties of anodes of Li, binary Li-Al alloys, ternary Li-Al-Cd, L i-AI-Si, Li-AI-Bi alloys were compared. The concentration range of alu minium in the alloys was used in accordance with a binary constitution al diagram. In a series of binary alloys with an Al content 5, 16.8, a nd 22.5 mass%, in the process of anode 'ageing', the alloy containing 16.8 mass% Al is passivated to a greater extent. Hence, cycling effici ency of lithium deposits changed. The increase in charge-current densi ty and the discharge-current density decrease raise the efficiency of lithium deposits. Comparison of the results of impedance measurements and galvanostatic cycling showed that the efficiency of galvanostatic cycling is higher when the active component of impedance is lower. The polarization of cathode process (deposition) and anode process (disso lution) decreases significantly in a series of lithium anodes: anodes on the basis of binary LI-AI alloys and anodes based on ternary alloys . Lithium insertion into the structure of ternary alloys proceeds cons iderably easier than into lithium or binary lithium-aluminium alloy st ructures. It may be conditioned by the binary alloy passivation in the electrolyte and by the less passivating film resistance on the ternar y alloys.