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3D collectors are combined with carbon buffer layers to effectively improve the electrochemical performance of silicon-based thin film anodes. [Display omitted] • 3D structure had sufficient suffer space. • Carbon layers could reduce interfacial resistance and increase its conductivity. • Top carbon layer prevented the active material from contacting with electrolyte. • Low self-weight collectors facilitate the electrochemical performance of anode. The application scope of silicon-based anode is limited by its poor electrical conductivity and massive volume expansion. Herein, we propose a method to modify electrochemical performance of silicon-based anode with 3D collector and carbon buffer layer by magnetron sputtering. With foam Ni as collector, at a current density of 1 A/g, the first reversible specific capacity reached 1973 mAh/g, and the specific capacity after 100 cycles was1700 mAh/g. With carbon cloth as collector, the first reversible specific capacity was 1543 mAh/g, and the specific capacity after 100 cycles was 1337 mAh/g. The 3D collector was used to buffer the internal stress caused by the bulk effect of silicon. The carbon buffer layer not only improved the material conductivity but also avoided the repeated growth of SEI film, thus providing more buffer space for silicon. This work provides a new promising solution to silicon-based lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Graphite anode suffers from severe performance fading at low temperature (LT) conditions mainly due to the suppressed diffusive Li+ storage mechanism in graphite anode at LT. Accordingly, the exploration of new type anodes with effective Li+ storage mechanism at LT is important. In this work, it is demonstrated that the utilization of the pseudo-capacitive storage mechanism could improve the Li+ storage kinetic at LT. In detail, a hybrid anode structure is designed via in-situ growth of MnO 2 nanosheets on the surface of the hollow carbon spheres (HCS@MO). Benefiting from the structural advantage, the as-prepared HCS@MO-09 electrode displays high reversible capacity of 455 mAh g-1 at 1 A g-1 at room temperature (RT) after 200 cycles. At − 20 ℃, the HCS@MO-09 electrode still exhibits high initial capacity of 432 mAh g-1 at 0.2 A g-1 and outstanding cycling stability. The cyclic voltammetry tests reveal that the superior LT performance of HCS@MO-09 electrode stems from the pseudo-capacitive storage mechanism. This work provides new perspective for improving LT performance through developing anodes with pseudo-capacitive storage mechanism. • The utilization of the pseudo-capacitive storage mechanism could improve the Li+ storage kinetic at low temperature. • A hybrid anode structure is designed via in-situ growth of MnO 2 nanosheets on the surface of the hollow carbon spheres. • The superior LT performance of HCS@MO-09 electrode stems from the pseudo-capacitive storage mechanism. [ABSTRACT FROM AUTHOR]