A high performance, binder-free flexible silicon electrode with high Si content up to 92% is developed for lithium ion batteries with a novel cellulose-based topological microscroll structure.

Structural materials with excellent mechanical properties are vitally important for architectural application. However, the traditional structural materials with complex manufacturing processes cannot effectively regulate heat flow, causing a large impact on global energy consumption. Here, we processed a high-performance and inexpensive cooling structural material by bottom-up assembling delignified biomass cellulose fiber and inorganic microspheres into a 3D network bulk followed by a hot-pressing process; we constructed a cooling lignocellulosic bulk that exhibits strong mechanical strength more than eight times that of the pure wood fiber bulk and greater specific strength than the majority of structural materials. The cellulose acts as a photonic solar reflector and thermal emitter, enabling a material that can accomplish 24-h continuous cooling with an average dT of 6 and 8 °C during day and night, respectively. Combined with excellent fire-retardant and outdoor antibacterial performance, it will pave the way for the design of high-performance cooling structural materials.

We modify Zn anodes with island-distributed indium (Zn@In). The effective suppression of hydrogen evolution by Zn@In enables an ultra-dense and rock-like Zn plating morphology, extending the cycling life of a Zn symmetrical cell to over one year.

Halide solid state electrolytes (SSEs) have attracted the attention of researchers as a new family of SSEs due to simple synthesis, high ionic conductivity, and good softness. However, until now, most of the reported works are focused on promotion of ionic conductivity, and little attention is paid to their air stability and degradation mechanism upon exposure. Herein, the degradation evolution of typical halide SSEs upon moisture is investigated in detail. It is found both Li 3 InCl 6 and Li 3 YCl 6 halide SSEs are easy to absorb water and deteriorate, and the air sensitivity is closely related to the contact area with air. In comparison, the water absorption rate of Li 3 InCl 6 is faster than that of Li 3 YCl 6 , while the amount of water absorption of Li 3 YCl 6 is larger than that of Li 3 InCl 6 , due to the higher solubility of InCl 3 compared to YCl 3 . Along with water absorption, Li 3 InCl 6 first forms a crystalline hydrate, then partially decomposes to InCl 3 and LiCl, and InCl 3 further hydrolyzes and produces acid which is corrosive; finally In 2 O 3 impurities are formed. Coating the surface of Li 3 InCl 6 with Al 2 O 3 can effectively improve the air stability. This work can help to understand the degradation mechanism of halide SSEs and provide guidance for the future design of new halide SSEs.

The poor electrochemical performance of Zn anodes at high current densities and large areal capacities is a tough challenge due to the accelerated dendrite growth and worsened reaction irreversibility. Herein, an ester-based organic, γ-butyrolactone (GBL), is utilized to regulate the deposition behaviors and performance of the Zn anode. Through DFT calculations, the strong interactions of GBL molecules with Zn 2+ and Zn slab were confirmed. In addition, improved interfacial properties were achieved, including the reduced potential of hydrogen evolution and enhanced wetting ability. Significantly, the concentration distribution difference of GBL between the Zn/electrolyte interface and the electrolyte was investigated by Raman spectra, and the interfacial preferential adsorption of GBL was highlighted. Electrochemical tests indicated that the supporting current density and the cycle life of the Zn anode using GBL could reach 30 mA cm −2 and 5000 h, respectively, proving the effectiveness of this strategy.C urrently, the world is working toward a cleaner society, which requires more efficient use of renewable energy to fill the gap of fossil fuels. 1,2 Considering the strict requirements for safety and economic effects, aqueous zinc-ion batteries (ZIBs) stand out as the most promising candidate for grid-scale energy storage, 3,4 which benefits greatly from the core merits of its Zn anode, including low cost, environmental friendliness, large capacity (820 mAh g −1 , 5855 mAh cm −3 ), and low redox potential (−0.76 V vs the standard hydrogen electrode). 5,6 However, the cycle life of ZIBs is seriously insufficient, especially at high current rates and large areal capacities, which is closely associated with the poor electrochemical performance of the Zn metal anode. It is well-known that uneven zinc deposition would naturally happen at the Zn anode, leading to rapid dendrite growth and causing the batteries' sudden failure. 7−9 Meanwhile, severe side reactions on the Zn anode will consume active Zn sources to reduce the Zn utilization and cause surface passivation to bring high battery resistance. 10−12 When the current density or areal capacity increases, the dendrites grow fast, and the loose structure with increased exposure surface exacerbates the side reactions and worsens the irreversibility. 13 Therefore, improving the cycle life of the zinc anode, especially at high current densities and large areal capacities, is a big challenge that has not been addressed to date.