실리콘계 음극의 초기 효율개선을 위한 용액 기반 화학적 리튬화 기술 개발
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이민아 KIST The redox activity of organic compounds has enriched chemistry of energy storage technology. One of the examples is solution-based chemical prelithiation using a reductive chemical. Prelithiation is of great interest to Li-ion battery manufacturers as a strategy for compensating for the loss of active Li during initial cycling of a battery with silicon-based high-capacity anodes, which would otherwise degrade its available energy density. The solution-based method promises unparalleled reaction homogeneity and simplicity in comparison with other prelithiation methods such as adding sacrificial additives to electrodes or making direct/indirect contact between Li metal and electrodes. The organic compounds applied so far, however, cannot dope active Li in Si-based anodes but merely form solid-electrolyte interphases, leading to only partial mitigation of the cycle irreversibility. I will present our recent work demonstrating a molecularly engineered Li-arene complex with a sufficiently low redox potential drives active Li accommodation in Si-based anodes to provide an ideal Li content in a full cell. Fine control over the prelithiation degree and spatial uniformity of active Li throughout the electrodes are achieved by managing time and temperature during immersion, promising both fidelity and low cost of the process for large-scale integration. |