Boron-Doped and Carbon-Controlled Porous Si/C Anode for High-Performance Lithium-Ion Batteries

Abstract

Silicon is a promising anode material for next generation lithium-ion batteries due to its high capacity and low discharge potential. Commercial silicon anodes are normally integrated with high graphite content to overcome their low electrical conductivity and huge cycling-induced volume change. However, this weakens the high specific capacity advantage of the silicon anode. Herein, a facile method based on the dealloying reaction of Mg2Si with CO2 and B2O3 was demonstrated for the synthesis of porous boron-doped silicon with low carbon content (pBSi-LC). Furthermore, the pBSi-LC anode showed high initial Coulombic efficiency of 89.3%, excellent rate performance (reversible capacity of 842 mAh g–1 at a high current density of 5A g–1), and long cycle stability (reversible capacity of 860 mAh g–1 at a current density of 2 A g–1 after 250 cycles).

Confined self-assembly of SiOC nanospheres in graphene film to achieve cycle stability of lithium ion batteries

“…The existence of the chemical bonds between BCO 2 and BC 2 O are mainly due to a C atom at the edge or defect site of the carbon skeleton being replaced by a B atom. 48 B doping can efficiently increase the concentration of electrons and holes in the hierarchical structure, thereby improving the electrochemical performance of B-SiOC@G. 49,50 The electrochemical performance was evaluated in half cells. Fig.…”

Co3O4 Quantum Dot-Catalyzed Lithium Oxalate as a Capacity and Cycle-Life Enhancer in Lithium-Ion Full Cells

“…These methods have achieved good results; however, owing to the formation of a solid electrolyte interphase (SEI) film and dead lithium on the anode surface, some active lithium in the cathode of the full battery will be consumed during the first cycle of battery charging. − This results in the reduction of battery capacity and energy density, and due attention has not been paid to this contributor to capacity loss. In contemporary graphite battery systems, the capacity loss is approximately 10%, whereas in next-generation high-capacity anodes (such as silicon or metal oxide), the capacity loss will reach >30%, which undoubtedly restricts the further development of high-energy lithium-ion batteries. , …”

“…In contemporary graphite battery systems, the capacity loss is approximately 10%, whereas in next-generation high-capacity anodes (such as silicon or metal oxide), the capacity loss will reach >30%, which undoubtedly restricts the further development of high-energy lithium-ion batteries. 7,8 Lithium compensation technology can be used to introduce additional Li-ions into the battery system, thereby solving the abovementioned problem. Contemporary lithium compensation technologies are mainly divided into two categories, namely, anode and cathode lithium compensation technolo-gies.…”

Si–Ni Nanofoam Composites with a 3D Nanoporous Structure as a High-Loading Lithium-Ion Battery Anode

“…The theoretical capacity of Si is as high as 3579 mAh g –1 , making Si the most promising anode material to break the upper limit of the energy density of lithium-ion batteries (LIBs). − However, pure Si electrodes have shortcomings such as poor conductivity, large structural changes during Li alloying and dealloying, and easy collapse, resulting in low initial Coulombic efficiency and cycle life, which limits their practical applications in LIBs. − Nanoporous metals, due to their unique metal properties (high conductivity and strong ductility) and nanomaterial properties (high porosity and large specific surface area), can effectively solve a series of problems caused by the volume expansion of Si materials during cycles. − …”