Al2O3-coated Li1.2Mn0.54Ni0.13Co0.13O2 nanotubes as cathode materials for high-performance lithium-ion batteries

Grafting a Polymer Coating Layer onto Li1.2 Ni0.13 Co0.13 Mn0.54 O2 Cathode by Benzene Diazonium Salts to Facilitate the Cycling Performance and High-Voltage Stability

Li-rich Mn-based cathodes have been regarded as promising cathodes for lithium-ion batteries because of their low cost of raw materials (compared with Ni-rich layer structure and LiCoO2 cathodes) and high energy density. However, for practical application, it needs to solve the great drawbacks of Li-rich Mn-based cathodes like capacity degradation and operating voltage decline. Herein, an effective method of surface modification by benzene diazonium salts to build a stable interface between the cathode materials and the electrolyte is proposed. The cathodes after modification exhibit excellent cycling performance (the retention of specific capacity is 84.2% after 350 cycles at the current density of 1 C), which is mainly attributed to the better stability of the structure and interface. This work provides a novel way to design the coating layer with benzene diazonium salts for enhancing the structural stability under high voltage condition during cycling.

Review of the Scalable Core-Shell Synthesis Methods: The Improvements of Li-Ion Battery Electrochemistry and Cycling Stability

The demand for lithium-ion batteries has significantly increased due to the increasing adoption of electric vehicles (EVs). However, these batteries have a limited lifespan, which needs to be improved for the long-term use needs of EVs expected to be in service for 20 years or more. In addition, the capacity of lithium-ion batteries is often insufficient for long-range travel, posing challenges for EV drivers. One approach that has gained attention is using core-shell structured cathode and anode materials. That approach can provide several benefits, such as extending the battery lifespan and improving capacity performance. This paper reviews various challenges and solutions by the core-shell strategy adopted for both cathodes and anodes. The highlight is scalable synthesis techniques, including solid phase reactions like the mechanofusion process, ball-milling, and spray-drying process, which are essential for pilot plant production. Due to continuous operation with a high production rate, compatibility with inexpensive precursors, energy and cost savings, and an environmentally friendly approach that can be carried out at atmospheric pressure and ambient temperatures. Future developments in this field may focus on optimizing core-shell materials and synthesis techniques for improved Li-ion battery performance and stability.

Li-Deficient Materials-Decoration Restrains Oxygen Evolution Achieving Excellent Cycling Stability of Li-Rich Mn-Based Cathode

With the increasing demand for high energy density and rapid charging performance, Li-rich materials have been the up and coming cathodes for next-generation lithium-ion batteries. However, because of oxygen evolution and structural instability, the commercialization of Li-rich materials is extremely retarded by their poor electrochemical performances. In this work, Li-deficient materials Li_0.3NbO₂ and (Nb_0.62Li_0.15)TiO₃ are applied to functionalize the surface of Li_1.2Mn_0.54Ni_0.13Co_0.13O₂, aiming to suppress oxygen evolution and increase structural stability in LIBs. In addition, a fast Li-ion transport channel is beneficial to enhance Li⁺ diffusion kinetics. The results demonstrate that the electrodes decorated with Li_0.3NbO₂ and (Nb_0.62Li_0.15)TiO₃ materials exhibit more stable cycling stability after long-term cycling and outstanding rate capability.

Recycling and Direct-Regeneration of Cathode Materials from Spent Ternary Lithium-Ion Batteries by Hydrometallurgy: Status Quo and Recent Developments : Economic recovery methods for lithium nickel cobalt manganese oxide cathode materials

The cathodes of spent ternary lithium-ion batteries (LIBs) are rich in nonferrous metals, such as lithium, nickel, cobalt and manganese, which are important strategic raw materials and also potential sources of environmental pollution. Finding ways to extract these valuable metals cleanly and efficiently from spent cathodes is of great significance for sustainable development of the LIBs industry. In the light of low energy consumption, ‘green’ processing and high recovery efficiency, this paper provides an overview of different recovery technologies to recycle valuable metals from cathode materials of spent ternary LIBs. Development trends and application prospects for different recovery strategies for cathode materials from spent ternary LIBs are also predicted. We conclude that a highly economic recovery system: alkaline solution dissolution/calcination pretreatment → H2SO4 leaching → H2O2 reduction → coprecipitation regeneration of nickel cobalt manganese (NCM) will become the dominant stream for recycling retired NCM batteries. Furthermore, emerging advanced technologies, such as deep eutectic solvents (DESs) extraction and one‐step direct regeneration/recovery of NCM cathode materials are preferred methods to substitute conventional regeneration systems in the future.

Enhanced Cathode Performance: Mixed Al2O3 and LiAlO2 Coating of Li1.2Ni0.13Co0.13Mn0.54O2

Li-rich, manganese-based cathode materials are attractive candidates for Li-ion batteries because of their excellent capacity, but poor rate and cycle performance have limited their commercial applications. Herein, Li-rich, manganese-based cathode materials were modified with aluminum isopropoxide as an aluminum source modifier using a sol-gel technique followed by a wet chemical method. To investigate the structure, morphology, electronic state, and elemental composition of both pristine- and surface-modified Li_1.2Ni_0.13Co_0.13Mn_0.54O₂, various characterizations were performed. Based on density functional theory simulations and the results of electrochemical tests, the surface of the modified cathode material was found to contain at least part of the LiAlO₂ phase. This was attributed to the aluminum isopropoxide reacting with a Li₂CO₃/LiOH byproduct on the material surface to form LiAlO₂ with a three-dimensional Li-ion channel structure. Electrochemical testing revealed that a 3 wt % aluminum isopropoxide coating of cathode materials exhibited excellent electrochemical performance. Furthermore, the initial Coulombic efficiency and discharge capacity at 0.1 C were up to 88.55% and 272.7 mAh g^-1, respectively. A final discharge capacity of 186.4 mAh g^-1 was achieved, corresponding to a capacity retention of 83.55% after 300 cycles at 0.5 C. This was attributed to LiAlO₂ partially accelerating the diffusion of Li ions and Al₂O₃ aiding the avoidance of side reactions in the mixed coating layer by partially protecting the structure.

Investigation of the structure and performance of Li[Li0.13Ni0.305Mn0.565]O2 Li-rich cathode materials derived from eco-friendly and simple coating techniques

Constructing uniform nanoceramic coating layers is a well-known challenge in the field of coating materials. Herein, Al₂O₃-coated Li[Li_0.13Ni_0.305Mn_0.565]O₂ (LLNM) Li-rich cathode materials are successfully prepared through a dry prilling coating (DPC) method. The structures and electrochemical performances of the Al₂O₃-coated products are systematically examined. Typically, the cycling stability is enhanced and voltage degradation upon cycling is reduced, benefiting from the unique and controllable nano-sized Al₂O₃ coating layer. Moreover, metal ion dissolution is avoided when using the DPC method, which is eco-friendly and suitable for large scale production.

Constructing uniform nanoceramic coating layers is a well-known challenge in the field of coating materials.

Temperature-Controlled Synthesis of Li- and Mn-Rich Li1.2Mn0.54Ni0.13Co0.13O2 Hollow Nano/Sub-Microsphere Electrodes for High-Performance Lithium-Ion Battery

The calcination temperature plays a significant role in the structural, textural, and energy-storage performance of metal oxide nanomaterials in Li-ion battery application. Here, we report the formation of well-crystallized homogeneously dispersed Li1.2Mn0.54Ni0.13Co0.13O2 hollow nano/sub-microsphere architectures through a simple cost-effective coprecipitation and chemical mixing route without surface modification for improving the efficiency of energy storage devices. The synthesized Li1.2Mn0.54Ni0.13Co0.13O2 hollow nano/sub-microsphere cathode materials are calcined at 800, 900, 950, and 1000 °C. Among them, Li1.2Mn0.54Ni0.13Co0.13O2 calcined at 950 °C exhibits a high discharge capacity (277 mAh g-1 at 0.1C rate) and excellent capacity retention (88%) after 50 cycles and also delivers an excellent discharge capacity of >172 mAh g-1 at 5C rate. Good electrochemical performance of Li1.2Mn0.54Ni0.13Co0.13O2-950 is directly related to the optimized size of its primary particles (85 nm) (which constitute the spherical secondary particle, ∼720 nm) and homogeneous cation mixing. Higher calcination temperature (≥950 °C) leads to an increase of the primary particle size, poor cycling stability, and inferior rate capacity of Li1.2Mn0.54Ni0.13Co0.13O2 due to smashing of quasi-hollow spheres upon repeated lithium ion intercalations/deintercalations. Therefore, Li1.2Mn0.54Ni0.13Co0.13O2-950 is a promising electrode for the next-generation high-voltage and high-capacity Li-ion battery application.