Li-phobicity of polyvinyl alcohol for the control of Li electrodeposition in Li-secondary batteries

As various types of new electrode designs for Li-secondary batteries are researched, development of technologies to control the electrodeposition of Li is required. Herein, the Li affinity of polyvinyl alcohol (PVA) is investigated to examine its applicability as a coating material for the control of Li plating position in battery anodes, via first-principle simulation and experimental studies. The simulation indicates that the oxygen ions in the PVA provide favorable adsorption sites for Li at the initial stage of Li deposition, but the sites are readily passivated because Li is combined with multiple O ions. Therefore, the binding force for the subsequent Li becomes weak and the PVA surface generally exhibits Li-phobic characteristics. The experiment of a patterned PVA coating on the Li-ion battery anode demonstrates the anti-Li-plating function of the PVA. From the investigation results, it is concluded that PVA is Li-phobic, and can be utilized for guiding the Li plating in the future design of Li-secondary battery anodes.

Automated summary

This study investigates the lithium affinity of polyvinyl alcohol (PVA) as a coating material for controlling lithium plating position in battery anodes. First-principle simulation and experimental studies show that PVA exhibits Li-phobic characteristics due to the weak binding force between subsequent lithium deposits and the PVA surface. The experiment of a patterned PVA coating on the Li-ion battery anode demonstrates its anti-Li-plating function.