The utilization of high‐voltage LiCoO2 is imperative to break the bottleneck of the practical energy density of lithium‐ion batteries. However, LiCoO2 suffers from severe structural and interfacial degradation at >4.55 V. Herein, a novel lattice‐matched LiCoPO4 coating is rationally designed for LiCoO2 which works at 4.6 V (vs Li/Li+) or above. This LiCoPO4 coating, derived by an in situ chemical reaction, grows epitaxially on LiCoO2 crystallite with strong bonding and complete coverage to LiCoO2, ensuring a stable cathode–electrolyte interface with fewer side reactions and alleviated intergranular cracking and phase collapse during repeated high‐voltage lithiation/delithiation processes. In addition, the formed strong covalent P–O tetrahedron configuration at the interface effectively decreases the surface oxygen activity of LiCoO2, further suppressing oxygen release and irreversible phase transition. Therefore, the LiCoPO4‐LiCoO2ǁLi cells display excellent capacity retention of 87% after 300 cycles at 4.6 V and stable operation at 4.6 V/55 °C or 4.7 V/30 °C. The strategy of lattice‐matching growth affords a new way to impact the development of high‐voltage LiCoO2 and beyond.

Li‐ion Batteries In article number 2200197, Yong Yang and co‐workers report a novel lattice‐coherent LiCoPO4 coating on LiCoO2 (LCO), derived by the in‐situ chemical reaction of Co(OH)2 and LiH2PO4, that can effectively alleviate irreversible structure transition and resist electrolyte corrosion, ensuring a high‐voltage LCO electrode (≥4.6V), and stable operation in portable electronic devices, such as mobile phones, computers, tablets, etc., to meet the high‐energy demand of the coming 5G era.

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The future energy needs have triggered research interest in finding novel energy storage systems with high energy density. Lithium–sulfur batteries are regarded as one of the most promising options for the next-generation energy storage applications because of their high theoretical energy and low cost. However, the electrochemical performances of lithium–sulfur batteries are seriously compromised by the polysulfide (LiPS) shuttling and the insulating nature of sulfur. To overcome these issues, novel CoNi1/3Fe2O4 (CNFO) nanoparticles uniformly covered on the carbon nanotubes are now reported as an efficient functional interlayer. Benefiting from the sufficient sulfiphilic sites of the CNFO for chemically bonding with LiPSs, as well as the conductive interconnected skeleton of carbon nanotubes, this composite material showed great enhancement on the rate capability and cycle stability of Li–S batteries. The Li–S battery using this interlayer exhibited a high initial capacity of 897 mA h g–1 and a low capacity decay of 0.063% per cycle within 250 cycles at 2 C. Meanwhile, an reversible specific capacity of 869 mA h g–1 (at 0.5 C) with high Coulombic efficiency could be obtained over 100 cycles at an elevated temperature (60 °C). We speculated that the chemical adsorption of CNFO for polysulfide-anchoring is extremely critical for the performances of Li–S batteries under high temperature.

Ni-rich materials have received widespread attention as one of the mainstream cathodes in high-energy-density lithium-ion batteries for electric vehicles. However, Ni-rich cathodes suffer from severe surface reconstruction in a high delithiation state, constraining their rate capabilities and life span. Herein, a novel P2-type Na x Ni0.33Mn0.67O2 (NNMO) is rationally selected as the surficial modification layer for LiNi0.8Co0.1Mn0.1O2 (NCM811) cathode, which undergoes a spontaneous Na+–Li+ exchange reaction to form an O2-type Li x Ni0.33Mn0.67O2 (LNMO) layer revealed by combining X-ray diffraction and solid-state nuclear magnetic resonance techniques. Owing to the specific oxygen stacking sequence, O2-type LNMO significantly prevents the initial layered structure of NCM811 from transforming to the spinel or rock-salt phases during cycling, thus effectively maintaining the integral surficial structure and the Li+ diffusion channels of NCM811. Eventually, the NNMO@NCM811 electrode yields enhanced thermal stability, outstanding rate performance, and long cycling stability with 80% capacity retention after 294 cycles at 200 mA g–1, and its life span is further extended to 531 cycles while enhancing the mechanical stability of the bulk material.