THE IN-SITU ANALYSIS OF INTERFACIAL REACTIONS BETWEEN ELECTRODE AND ORGANIC ELECTROLYTES II - ELECTRODEPOSITION OF LITHIUM AT CU ELECTRODE

We investigated the effects of electrolytes on the electrodeposition o f lithium at Cu electrode using in situ FTIR and AFM measurements. The electrolyte solutions used were EC+DMC and EC+DEC each including 1 mo l/dm(3) LiPF6. The AFM observation showed that the electrodeposition o f lithium occurred as a formation of small particles about 0.51 mu m i n size and several particles combined and grew up larger than 1 mu m a t Cu electrodes. As the effects of DEC, the particle size of deposited lithium grew larger than in EC+DMC system, especially at a charging c urrent density of 1 mA/cm(2). The in situ FTIR spectroscopy showed the difference in the surface reaction with deposited lithium in EC+DMC a nd in EC+DEC system.