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Nanostructured electrode materials are good candidates in batteries especially for high‐rate applications, yet they often suffer from extensive side reactions due to anomalously large surface areas. While micrometer‐size materials provide better stability, the lattice diffusivity is often too slow for lithium ion intercalation over the same length scale in a short time. Herein, a simple method to synthesize glass‐ceramic‐like vanadate cathodes for lithium‐ion batteries with abundant internal boundaries that allow fast lithium ion diffusion while maintaining a small surface area that thus minimize the contact and side reactions with organic electrolyte, is reported. Such samples heat‐treated under optimized conditions can deliver an impressive high‐rate capacity of 103 mAh g−1 at 4000 mA g−1 over 500 cycles, which has better kinetics and cycling stability than similar vanadate‐based materials. A striking grain‐size refinement effect accompanied by a low‐temperature growth‐controlled phase transition, can be achieved by fine tuning the heat‐treatment process. It is believed that the findings are general for other transition metal oxides for energy applications. [ABSTRACT FROM AUTHOR]

Lithium-Ion Batteries: Glass-Ceramic-Like Vanadate Cathodes for High-Rate Lithium-Ion Batteries (Adv. In article number 1903411, Shitong Wang, Yanhao Dong, Zilong Tang, and co-workers demonstrate that glass-ceramic vanadate cathodes can be easily obtained by fine tuning the heat treatment process, offering abundant internal boundaries that facilitate lithium-ion diffusion and minimize side reactions. Batteries, cathodes, kinetics, microstructures, vanadate. [Extracted from the article]

Spinel LiMn 2 O 4 is a promising cathode candidate for lithium ion batteries whose electrochemical properties strongly depend on the surface orientation. In this work, we have successfully synthesized a high crystalline and well-defined truncated octahedral LiMn 2 O 4 through the hydrothermal and heat treatment. The main {111} facets are aligned along the orientations mitigating Mn dissolution while the truncated {100} and {110} facets are along those facilitating Li + diffusion. Benefiting from the unique structure, the octahedral LiMn 2 O 4 delivers 143.4 mAh g −1 (close to the theoretical capacity of 148 mAh g −1 ) at 0.2 C and over 120 mAh g −1 at 30 C (discharged within 2 min) at 55 °C. Moreover, the fabricated LiMn 2 O 4 /Li 4 Ti 5 O 12 -TiO 2 full cell demonstrates 121.6 mAh g −1 at 1 C and 56.0 mAh g −1 at 30 C with ∼81.2% capacity retention following 1000 cycles. The facilely synthesized truncated octahedral LiMn 2 O 4 shows great potentials in practical applications for ultrafast and long-life lithium-ion batteries. [ABSTRACT FROM AUTHOR]

Abstract: Reducing the particle size and coating conductive materials are both effective ways to improve the performance of LFP (LiFePO4). In this paper, we synthesized LFP/C/CPO (LiFePO4/C/CePO4) composites and investigated the effects of CePO4 modification on the morphologies and electrochemical properties of LFP/C composites. The results demonstrated that introducing CePO4 nanoparticles via in situ method could reduce the particle size significantly and improve the electrochemical properties of LFP/C. [Copyright &y& Elsevier]

Abstract: Novel lithium titanate hydrate nanotubes for lithium ion batteries have been easily prepared via a hydrothermal method. This material demonstrates high energy density, outstanding rate capabilities and a very long cycle life comparable to those of supercapacitors. At a rate equivalent to a 10-min total charge/discharge, the as-prepared lithium titanate hydrate nanotubes exhibit a life of over 5000 charge/discharge cycles while still retaining up to 86.3% of its original capacity. The abilities of lithium titanate hydrate nanotubes to fully charge within minutes for thousands of times and still retain a large capacity may find promising applications in hybrid and plug-in hybrid electric vehicles. [ABSTRACT FROM AUTHOR]

Abstract: LiFePO4/carbon composite cathode material was prepared using polyvinyl alcohol (PVA) as carbon source by pelleting and subsequent pyrolysis in N2. The samples were characterized by XRD, SEM and TGA. Their electrochemical performance was investigated in terms of charge–discharge cycling behavior. It consists of a single LiFePO4 phase and amorphous carbon. The special micro-morphology via the process is favorable for electrochemical properties. The discharge capacity of the LiFePO4/C composite was 145mAh/g, closer to the theoretical specific capacity of 170mAh/g at 0.1C low current density. At 3C modest current density, the specific capacity was about 80mAh/g, which can satisfy for transportation applications if having a more planar discharge flat. [Copyright &y& Elsevier]