High-performance anode of lithium ion batteries with plasma-prepared silicon nanoparticles and a three-component binder. (10th September 2021) - Wang, Fangfang
Highlights: The crystalline silicon nanoparticles coated with an amorphous silicon layer (a-coated-c-SiNPs) were continuously prepared by non-thermal plasma pyrolyzing of silane with the help of hydrogen and argon. The a-Si layer with good tolerance to volume expansion prevented the electrode pulverization, while the c-Si improved the electronic conductivity. The crystallinity of the a-coated-c-SiNPs was controled by the hydrogen etching. The combination of a-coated-c-SiNPs with a three-component polymer binder (PAA-PVA/SBR) improved the electrochemical performance of Si-based anode. Abstract: The crystalline silicon nanoparticles coated with an amorphous silicon layer was prepared by continuously pyrolysing the mixture of silane and hydrogen in a non-thermal arc plasma reactor. The hydrogen in the gas mixture effectively controls the thickness of the amorphous silicon layer and further improves the electrochemical performance of the silicon anode. The mechanism of the hydrogen was investigated by experiments. At the same time, a three-component polymer binder was concocted and introduced to tolerate the volume expansion of silicon effectively. Combining the silicon nanoparticles prepared at the optimal conditions with the novel polymer binder, the resulting silicon anode exhibits excellent electrochemical performance of 2120 mAh g −1 at 400 mA g −1 after 100 cycles. Graphical abstract: Image, graphical abstract