Although silicon is a promising anode material for lithium-ion batteries, scalable synthesis of silicon anodes with good cyclability and low electrode swelling remains a significant challenge. Herein, we report a scalable top-down technique to produce ant-nest-like porous silicon from magnesium-silicon alloy. The ant-nest-like porous silicon comprising three-dimensional interconnected silicon nanoligaments and bicontinuous nanopores can prevent pulverization and accommodate volume expansion during cycling resulting in negligible particle-level outward expansion. The carbon-coated porous silicon anode delivers a high capacity of 1,271 mAh g −1 at 2,100 mA g −1 with 90% capacity retention after 1,000 cycles and has a low electrode swelling of 17.8% at a high areal capacity of 5.1 mAh cm −2 . The full cell with the prelithiated silicon anode and Li(Ni 1/3 Co 1/3 Mn 1/3 )O 2 cathode boasts a high energy density of 502 Wh Kg −1 and 84% capacity retention after 400 cycles. This work provides insights into the rational design of alloy anodes for high-energy batteries.

Binder plays a key role in maintaining the mechanical integrity of electrodes in lithium-ion batteries. However, the existing binders typically exhibit poor stretchability or low conductivity at large strains, which are not suitable for highcapacity silicon (Si)-based anodes undergoing severe volume changes during cycling. Herein, a novel stretchable conductive glue (CG) polymer that possesses inherent high conductivity, excellent stretchablity, and ductility is designed for high-performance Si anodes. The CG can be stretched up to 400% in volume without conductivity loss and mechanical fracture and thus can accommodate the large volume change of Si nanoparticles to maintain the electrode integrity and stabilize solid electrolyte interface growth during cycling while retaining the high conductivity, even with a high Si mass loading of 90%. The Si-CG anode has a large reversible capacity of 1500 mA h g −1 for over 700 cycles at 840 mA g −1 with a large initial Coulombic efficiency of 80% and high rate capability of 737 mA h g −1 at 8400 mA g −1 . Moreover, the Si-CG anode demonstrates the highest achieved areal capacity of 5.13 mA h cm −2 at a high mass loading of 2 mg cm −2 . The highly stretchable CG provides a new perspective for designing next-generation high-capacity and high-power batteries.

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In this paper, a scheme for specifying contact angle and its hysteresis is incorporated into a multiphase lattice Boltzmann method. The scheme is validated through investigations of the dynamic behaviors of a droplet sliding along two kinds of walls: a smooth (ideal) wall and a rough or chemically inhomogeneous (nonideal) wall. For an ideal wall, the wettability of solid substrates is able to be prescribed. For a nonideal wall, arbitrary contact angle hysteresis can be obtained through adjusting advancing and receding angles. Significantly different phenomena can be recovered for the two kinds of walls. For instance, a droplet on an inclined ideal wall under gravity is impossible to stay stationary. However, the droplet on a nonideal wall may be pinned due to contact angle hysteresis. The steady interface shapes of the droplet on an inclined nonideal wall under gravity or in a shear flow quantitatively agree well with the previous numerical studies. Besides, the complex motion of a droplet creeping like an inchworm could be simulated. The scheme is found suitable for the study of contact line problems with and without contact angle hysteresis.

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Peapod-like Ge/CNx is designed as a high-performance anode for lithium-ion batteries, which boasts high capacity, excellent cyclability and rate capability.