Durable flexible dual-layer and free-standing silicon/carbon composite anode for lithium-ion batteries

Although silicon is currently recognized as the most promising anode material for lithium-ion batteries, its industrial application is still a major challenge due to its poor electronic conductivity and volume expan-sion. Herein, a kind of flexible silicon/carbon composite with dual-layer is prepared by microelectronic printing technology and be used as anode for lithium-ion batteries, which can be molded in one shot without addition of binders and conductive agents. A slit structure exists in the layers in the anode which can provide an elastic room to buffer volume expansion during lithiation/delithiation. An amorphous carbon protective shell pyrolyzed from PVP can improve the structure stability and electrochemical per-formance of the microelectronic printed pole piece. At a current density of 0.1 A/g, a reversible capacity of 941.1 mAh g(-1) can be obtained, the first Coulomb efficiency is 79%. After 100 cycles, the capacity retention rate is 81.82%. In the step current rate performance test, it is 421.6 mAhg(-1)at 1.0 A/g, and the capacity retention rate can reach 98.67% after 50 cycles. This work provides a rational design strategy of flexible anodes for high-capacity lithium-ion batteries. (C) 2022 Elsevier B.V. All rights reserved.