Combustion combined with ball milling to produce nanoscale La2O3 coated on LiMn2O4 for optimized Li-ion storage performance at high temperature

Recent progress on the low and high temperature performance of nanoscale engineered Li-ion battery cathode materials

Lithium ion batteries (LIB) are the domain power house that gratifies the growing energy needs of the modern society. Statistical records highlight the future demand of LIB for transportation and other high energy applications. Cathodes play a significant role in enhancement of electrochemical performance of a battery, especially in terms of energy density. Therefore, numerous innovative studies have been reported for the development of new cathode materials as well as improving the performance of existing ones. Literature designate stable cathode-electrolyte interface (CEI) is vital for safe and prolonged high performance of LIBs at different cycling conditions. Considering the context, many groups shed light on stabilizing the CEI with different strategies like surface coating, surface doping and electrolyte modulation. Local temperature variation across the globe is another major factor that influences the application and deployment of LIB chemistries. In this review, we discuss the importance of nano-scale engineering strategies on different class of cathode materials for their improved CEI and hence their low and high temperature performances. Based on the literature reviewed, the best nano-scale engineering strategies investigated for each cathode material have been identified and described. Finally, we discuss the advantages, limitations and future directions for enabling high performance cathode materials for a wide range of applications.

A nano-truncated Ni/La doped manganese spinel material for high rate performance and long cycle life lithium-ion batteries

A nano-truncated octahedral LiNi0.08La0.01Mn1.91O4 cathode material with {111} and {100} crystal planes achieves capacity retention of 89.0% after 1000 cycles at 10C.

Enhancing Lithium Manganese Oxide Electrochemical Behavior by Doping and Surface Modifications

Lithium manganese oxide is regarded as a capable cathode material for lithium-ion batteries, but it suffers from relative low conductivity, manganese dissolution in electrolyte and structural distortion from cubic to tetragonal during elevated temperature tests. This review covers a comprehensive study about the main directions taken into consideration to supress the drawbacks of lithium manganese oxide: structure doping and surface modification by coating. Regarding the doping of LiMn2O4, several perspectives are studied, which include doping with single or multiple cations, only anions and combined doping with cations and anions. Surface modification approach consists in coating with different materials like carbonaceous compounds, oxides, phosphates and solid electrolyte solutions. The modified lithium manganese oxide performs better than pristine samples, showing improved cyclability, better behaviour at high discharge c-rates and elevated temperate and improves lithium ions diffusion coefficient.

Controllable Fabrication and Li Storage Kinetics of 1 D Spinel LiMn2 O4 Positive Materials for Li-ion Batteries: An Exploration of Critical Diameter

The morphology and size of nanoelectrode materials determine their properties. Compared to the bulk structure electrodes, 1 D electrode materials for Li-ion batteries have been intensively studied owing to their excellent Li⁺ diffusion kinetics. It is generally accepted that smaller-sized electrode materials lead to better Li storage kinetics. In this study, this is found to not be the case in 1 D LiMn₂ O₄ positive materials. A facile strategy of manipulating the KMnO₄ concentration is introduced to precisely fabricate 1 D LiMn₂ O₄ nanorods with four distinct diameter gradients from 30 to 170 nm. The role of 1 D crystal size in effecting interface chemical species and electrochemical performance is elucidated by comparative characterization methods. X-ray photoelectron spectroscopy (XPS) Ar-ion etching technology shows that the Mn²⁺ is electrochemically inactive on the surface of the sample, which explains the adverse effects observed on LiMn₂ O₄ nanorods with the minimum diameter of 30-40 nm, such as decreased discharge capacity. The LiMn₂ O₄ nanorod with a critical diameter of approximately 70-80 nm displays the highest discharge capacity and promising cycling performance. This work clarifies an important property that has previously been neglected and deepens the understanding for design of Mn-based positive materials.