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Microporous nitrogen‐doped carbons produced by hydrothermal carbonization of biomass derivative followed by chemical activation showed excellent supercapacitive capacitance performance both in acid and base electrolytes.

Lithium metal is considered a "Holy Grail" of anode materials for highenergy-density batteries. However, both dendritic lithium deposition and infinity dimension change during long-term cycling have extremely restricted its practical applications for energy storage devices. Here, a thermal infusion strategy for prestoring lithium into a stable nickel foam host is demonstrated and a composite anode is achieved. In comparison with the bare lithium, the composite anode exhibits stable voltage profiles (200 mV at 5.0 mA cm −2 ) with a small hysteresis beyond 100 cycles in carbonate-based electrolyte, as well as high rate capability, significantly reduced interfacial resistance, and small polarization in a full-cell battery with Li 4 Ti 5 O 12 or LiFePO 4 as counter electrode. More importantly, in addition to the fact that lithium is successfully confined in the metallic nickel foam host, uniform lithium plating/stripping is achieved with a low dimension change (merely ≈3.1%) and effective inhibition of dendrite formation. The mechanism for uniform lithium stripping/ plating behavior is explained based on a surface energy model.

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Solid polymer electrolytes with high ionic conductivities are prepared by using poly(ethylene oxide) (PEO) and poly(vinylidene fluoride‐co‐hexafluoropropylene) (P(VDF‐HFP)) as polymer matrixes, succinonitrile (SN) as an additive, and lithium bis‐trifluoromethanesulfonimide (LiTFSI) and lithium bisperfluoroethylsulfonylimide (LiBETI) as salts. In these systems, the introduction of succinonitrile into the polymer electrolytes increases the material's ionic conductivity and conveys excellent mechanical properties. The described composites, with their beneficial combination of mechanical and electric properties, are expected to have significant potential for lithium batteries.

A high‐performance polyaniline electrode was prepared by potentiostatic deposition of aniline on a hierarchically porous carbon monolith (HPCM), which was carbonized from the mesophase pitch. A capacitance value as high as 2200 F g–1 (per weight of polyaniline) is obtained at a power density of 0.47 kW kg–1 and an energy density of 300 W h kg–1. This active material deposited on HPCM also has the advantageous of high stability. These properties can be essentially attributed to the backbone role of HPCM. The method also has the advantage of a topology that is favorable for kinetics at high power densities, thus, contributing to the increase of ionic conductivity and power density. There is also no need for a binder, which not only lowers the preparation costs but also offers advantages in terms of stability and performance.

The ever-increasing energy density of the Li-ion battery calls for utilization of high-capacity cathodes and anodes, which tend to be more reactive and thus bring serious safety concern. Under such context, the solid-state Li battery becomes a hotspot because of its potential in the breakthrough of energy density as well as the avoidance of uncontrollable chemical reactions. Recently, many review and perspective papers appear, addressing the urgency of improving solid-electrolytes' ionic conductivity and constructing stable conductive interfaces between electrolyte and electrode with respect to available electrolytes, including polymers, nitrides, sulfides, and oxides. Nevertheless, each type of electrolyte has its own distinctive problems, which is worthwhile specifically elaborating in order to find effective solutions. Therefore, here, we present our viewpoints on the key issues related to the garnet electrolytes and relevant batteries, which have not ever been dedicatedly addressed previously. On the basis of our recent progress, together with others reported in the literature, we expect that the solid garnet batteries are promising for application if the best use is made of garnet advantages and disadvantages are bypassed.

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