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Summary: High‐Ni layered‐oxide cathodes are the most prospective cathode materials for next‐generation Li‐ion batteries (LIBs) in electric vehicles (EVs) owing to their high specific capacity. However, High‐Ni layered‐oxide cathode materials exhibit inferior cyclability and low thermal stability owing to the side reaction between Ni4+ and the electrolytes. To solve these surface‐related problems, we proposed a strategy for forming LiNbO3 (LNO)—with outstanding thermal stability and ionic conductivity—on a Ni‐rich layered‐oxide surface using polydopamine (PDA). The PDA formed on the transition metal hydroxide surface has copious catechol OH groups, which attract the Nb ions in the solution to form a LNO coating layer during the calcination process. The LiNi0.8Co0.1Mn0.1O2 (pristine LNCM) electrode experiences enormous degradation when cycled after being subjected to severe conditions—such as a full charge and a 60°C storage test—but the LiNbO3‐coated LNCM (LNO‐LNCM) electrode exhibits particularly stable cycling performance. Furthermore, differential scanning calorimetry (DSC) results exhibited that the LNO coating notably ameliorated the thermal stability of the cathode material. As a result, our experimental results suggest that the development of cathode materials that can withstand greatly oxidized states and high‐temperature environments is achievable. [ABSTRACT FROM AUTHOR]

A heterostructured porous carbon framework (PCF) composed of reduced graphene oxide (rGO) nanosheets and metal organic framework (MOF)-derived microporous carbon is prepared to investigate its potential use in a lithium-ion battery. As an anode material, the PCF exhibits efficient lithium-ion storage performance with a high reversible specific capacity (771 mA h g−1 at 50 mA g−1), an excellent rate capability (448 mA h g−1 at 1000 mA g−1), and a long lifespan (75% retention after 400 cycles). The in situ transmission electron microscopy (TEM) study demonstrates that its unique three-dimensional (3D) heterostructure can largely tolerate the volume expansion. We envisage that this work may offer a deeper understanding of the importance of tailored design of anode materials for future lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Mesoporous lithium metal phosphates are an important class of materials for the development of lithium ion batteries. However, there is a limited success in producing mesoporous lithium metal phosphates in the literature. Here, a lyotropic liquid crystalline (LLC) templating method was employed to synthesize the first examples of LiMPO4 (LMP) of Mn(II), Co(II), and Ni(II). A homogeneous aqueous solution of lithium and transition metal nitrate salts, phosphoric acid (PA), and surfactant (P123) can be spin coated or drop‐cast coated over glass slides to form the LLC mesophases which can be calcined into mesoporous amorphous LMPs (MA‐LMPs). The metal salts of Mn(II), Co(II) and Ni(II) produce MA‐LMPs that crystallize into olivine structures by heat treatment of the LLC mesophase. The Fe(II) compound undergoes air oxidation. Therefore, both Fe(II) and Fe(III) precursors produce a crystalline Li3Fe2(PO4)3 phase at over 400 °C. The MA‐LMPs show no reactivity towards lithium, however the crystalline iron compound exhibits electrochemical reactivity with lithium and a good electrochemical energy storage ability using a lithium‐ion battery test. [ABSTRACT FROM AUTHOR]

Due to vast sodium reserves, sodium-ion batteries (SIBs) are more cost-efficient to produce than lithium-ion batteries. Therefore, they are actively researched as next-generation energy storage materials. Antimony is a promising anode material for SIB owing to its high theoretical capacity (660 mA h g−1) and an appropriate sodiation voltage. However, due to the rapid volume change during sodium intercalation and deintercalation, cycling stability is poor, presenting a significant obstacle to the practical application of SIBs. Alleviating the Sb volume expansion throughout the charging and discharging processes is the key to the practical implementation of Sb-based anodes. Herein, Sb/C–SiOC composites are prepared using the hydrogen bonding-based adsorption properties of metal-organic frameworks (MOFs). The final product, the Sb/C–SiOC composites, exhibited significantly improved cycle performance, such as maintaining the initial capacity after 200 cycles by the SiOC matrix acting as a conductive buffer. Additionally, the presence of MOF-derived mesoporous carbon and SiOC contributed to the improved rate performance. The hydrogen bond-based adsorption properties of the MOFs used in this study can be effectively applied to uniformly introduce a matrix or coating layer that relieves the volume expansion of high-capacity composite anodes, making it an effective strategy for developing alloy-based energy storage materials. [Display omitted] • A novel Sb-MOFs composites with improved dispersion properties was synthesized. • In the final composites, Sb particles were evenly embedded into the SiOC matrix. • The SiOC matrix effectively accommodates volume expansion of Sb materials. • The MOF-derived mesoporous carbon enhances the electrochemical kinetics. • Hydrogen bond-based dispersion properties of composites can be utilized widely. [ABSTRACT FROM AUTHOR]

[Display omitted] • The homogeneous coating layer is formed using electrostatic force of the polymer. • Li 3 VO 4 -coated LiNi 0.5 Mn 1.5 O 4 are synthesized simultaneously by a single calcination step. • Nanoscale Li 3 VO 4 coating improves the LiNi 0.5 Mn 1.5 O 4 performance. • Li 3 VO 4 coating layer increases Li-ion access and conductivity. • Li 3 VO 4 layer effectively suppresses side reactions at elevated temperatures. One of the most promising high voltage cathode materials for application in lithium ion batteries (LIBs), the 5 V spinel LiNi 0.5 Mn 1.5 O 4 , faces electrode/electrolyte decomposition at high voltage, rendering commercial application difficult. To overcome these obstacles, this study proposes a method for adsorbing vanadium anion complexes on the surface of Ni 0.25 Mn 0.75 (OH) 2 using cationic polymers and calcination them with LiOH to form LiNi 0.5 Mn 1.5 O 4 with a uniform nano-Li 3 VO 4 coating layer. The uniform nano-Li 3 VO 4 coating layer prepared by the above method promotes transfer of lithium ions and protects active material from electrolyte corrosion, thereby obtaining a particularly stable electrochemical performance under severe operating conditions such as high temperatures. Electrochemical tests show that the Li 3 VO 4 -coated LiNi 0.5 Mn 1.5 O 4 demonstrates a high discharge capacity and at the cycling test after storage test at 60 °C, the Li 3 VO 4 -coated LiNi 0.5 Mn 1.5 O 4 shows higher capacity retention than pristine LiNi 0.5 Mn 1.5 O 4 ; this can be attributed to the coating that acts as a protective layer. [ABSTRACT FROM AUTHOR]

[Display omitted] • The nanoscale coating layer is successfully formed using PDA modification. • A synchronous lithiation strategy is used to the surface modification. • The Li 6.25 La 3 Zr 2 Al 0.25 O 12 coating improves the LiNi 0.88 Co 0.05 Mn 0.07 O 2 performance. • The fast ionic conductor coating layer facilitate Li-ion migration. • The protective layer effectively suppresses side reactions during long-term cycling. Ni-rich cathode materials have promising applications in lithium-ion batteries owing to their high energy density and reasonable cost. The surface stabilization of these materials is vital for achieving excellent electrochemical performance. In this study, a fast ionic conductor, Li 6.25 La 3 Zr 2 Al 0.25 O 12 (LLZAO), was successfully coated on the surface of LiNi 0.88 Co 0.05 Mn 0.07 O 2 (LNCM) using a polydopamine (PDA) modification method. The abundant catechol groups of the intermediate PDA layer on the Ni 0.88 Co 0.05 Mn 0.07 (OH) 2 (NCM(OH) 2) precursor attracted metal ions in an aqueous solution, and a uniform LLZAO coating layer was formed after calcination under an O 2 flow. The presence of the LLZAO protective film on the surface of LNCM was confirmed using several characterization techniques. The LLZAO-coated LNCM exhibited superior electrochemical properties compared to those of the pristine LNCM. Moreover, the LLZAO-coated LNCM demonstrated excellent electrochemical stability even at a high temperature (60 ℃). The deterioration of the surface structure of LNCM was significantly suppressed by the formation of the LLZAO coating layer, and LLZAO improved the Li+ ion transport at the electrode/electrolyte interface. [ABSTRACT FROM AUTHOR]

A submicron spherical silicon oxycarbide (SiOC) material for lithium-ion battery anodes was successfully synthesized by employing a facile synthetic strategy that used economical silicone oil as a starting material, an emulsion method, and the subsequent pyrolysis of silicone oil emulsion at 900 °C. Although most previous studies concerning silicone-oil-based SiOC exhibited irregular and uncontrollable size after synthesis, the developed emulsion-driven SiOC preparation achieved regular submicron spherical particles. Furthermore, the emulsifier used herein formed a thin carbon coating layer after the synthesis procedure and contributed to the electrochemical performance during battery operation. The spherical submicron size-controlled SiOC material had superior capacity retention compared to pristine SiOC obtained without the emulsion method, owing to the suppressed micro-cracks induced by accumulation of mechanical stress during repeated cycles and prevention of direct contact with the electrolyte by the thin carbon-coating layer. [Display omitted] • SiOC from cheap silicone oil was synthesized by a facile emulsion method. • The emulsion-driven SiOC preparation achieved regular submicron spherical particles. • The size-controlled SiOC material mitigates the volume expansion of the electrode. • Size-controlled SiOC can prevent side reactions by a thin carbon-coating layer. • The spherical submicron size-controlled SiOC had superior capacity retention. [ABSTRACT FROM AUTHOR]