Among all the possible anode materials for next-generation rechargeable batteries, lithium (Li) metal stands out from the crowd for its high specific capacity and low redox potential. Unfortunately, the issues caused by Li dendrites limit the commercialization of the batteries based on Li metal anodes. Research in recent years has proved that the Li dendrites cannot be completely eliminated. Inspired by the Chinese legend, "King Yu Tamed the Flood," the new strategy of combing dredge and block, to control the diversion of Li ions is proposed. Via Au modification on one side of the carbon fibers matrix (CFs@Au), selective deposition of Li ions on the back side of the current collector is successfully achieved. This is distant from the separator, and hence improves the safety effectively. As a result, the Coulombic efficiency of the CFs@Au-Li anode remains 99.2% throughout 400 cycles. What is more, the Li-S full cell paired with the composite anode also exhibits outstanding performance, even with limited Li. This backside-deposition strategy provides new insight into safe Li metal anode design for high energy density battery systems such as Li-S and Li-O 2 .

Lithium metal is widely studied as the “crown jewel” of potential anode materials due to its high specific capacity and low redox potential. Unfortunately, the Li dendrite growth limits its commercialization. Previous research has revealed that the uniform Li‐ion flux on electrode surface plays a vital role in achieving homogeneous Li deposition. In this work, a new strategy is developed by introducing a multifunctional Li‐ion pump to improve the homogenous distribution of Li ions. Via coating a β‐phase of poly(vinylidene fluoride) (β‐PF) film on Cu foil (Cu@β‐PF), a piezoelectric potential across such film is established near the electrode surface because of its piezoelectric property, which serves as a driving force to regulate the migration of Li ions across the film. As a result, uniform Li‐ion distribution is attained, and the Cu@β‐PF shows coulombic efficiency around 99% throughout 200 cycles. Meanwhile, the lithium‐sulfur full cell paired with Li‐Cu@β‐PF anode exhibits excellent performance. This facile strategy via regulating the Li‐ion migration provides a new perspective for safe and reliable Li metal anode.

A rational compositional design is critical for utilizing LiNiO2‐based cathodes with Ni contents > 90% as promising next‐generation cathode materials. Unfortunately, the lack of a fundamental understanding of the intrinsic roles of key elements, such as cobalt, manganese, and aluminum, makes the rational compositional design of high‐Ni cathodes with a limited range of dopants (<10%) particularly challenging. Here, with 5% single‐element doped cathodes, viz., LiNi0.95Co0.05O2, LiNi0.95Mn0.05O2, and LiNi0.95Al0.05O2, along with undoped LiNiO2 (LNO), the influences of the dopants are systematically examined through a control of cutoff charge energy density and a common practice of cutoff charge voltage. Comprehensive investigations into the electrochemical properties, combined with in‐depth analyses of the structural and interfasial stabilities and electrolyte decomposition pathways through advanced characterizations, unveil the following: i) the intrinsic role of dopants regulates the cathode energy density or state‐of‐charge and, more critically, the occurrence of H2–H3 phase transition, which essentially dictates cyclability; ii) undoped LNO can be stabilized well with the avoidance of H2–H3 phase transition; and iii) Co provides more merits overall with an optimized electrochemical operating condition. This work provides guidance for the compositional design of high‐energy‐density high‐Ni cathodes and sheds light on the challenges of removing Co.

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The well‐known “shuttle effect” of the intermediate lithium polysulfides (LiPSs) and low sulfur utilization hinder the practical application of lithium–sulfur (Li–S) batteries. Herein, we describe a novel C60–S supramolecular complex with high‐density active sites for LiPS adsorption that was formed by a simple one‐step process as a cathode material for Li–S batteries. Benefiting from the cocrystal structure, 100 % of the C60 molecules in the complex can offer active sites to adsorb LiPSs and catalyze their conversion. Furthermore, the lithiated C60 cores promote internal ion transport inside the composite cathode. At a low electrolyte/sulfur ratio of 5 μL mg−1, the C60–S cathode with a sulfur loading of 4 mg cm−2 exhibited a high capacity of 809 mAh g−1 (3.2 mAh cm−2). The development of the C60–S supramolecular complex will inspire the invention of a new family of S/fullerenes as cathodes for high‐performance Li–S batteries and extend the application of fullerenes.

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