Si-based composite deriving from wok ash waste as high-performance anode for Li-ion battery

Abstract

For the first time, wok ash (W-A) is exploited to be an anode material for lithium-ion batteries (LIBs). It contributes to the elimination of obstacles that appear on the commercial progress of silicon (Si) anodes. Herein, a composite of W-A, carbon nanotubes (CNTs) and commercial Si nanoparticles, denoted as C1Si2@W-A2, is designed and fabricated, which is synthesized by simply one-step ball milling. To coordinate with Si, W-A’s nanoporous structure alleviates volume expansion during the lithiation/delithiation process. Interestingly, owing to the existence of multiple oxides in W-A, the capacity of the whole electrode increases after several cycles. As a result, the optimized C1Si2@W-A2 can deliver a capacity of 1528.8 mA h g−1 after 100 cycles at a current density of 100 mA g−1 and earn a decent rate performance. In addition, the energy storage mechanism is explored by quantitative kinetics analysis and proven to be a capacitance-battery dual model. Hopefully, favorable electrochemical performance and low-cost make C1Si2@W-A2 a potential candidate for LIBs anode, paving the way for the commercialization of Si nanoparticles.