Search

Silicon oxide (SiOx) is recognized as a promising anode material for high-energy lithium-ion batteries (LIBs) due to its abundant reserves, facile synthesis, and high theoretical capacity. However, the practical use of the SiOx anode is severely hampered due to its poor cycling stability caused by a large volume change upon lithiation/delithiation. The waterborne poly(acrylic acid) (PAA) binder has been regarded as one of the most promising binders for SiOx-based anodes. In this work, a new concept is developed using locally an enriched PAA binder to enhance the structural stability of the electrode, the adhesion force between the electrode and the current collector, and the dispersion of carbon black within the electrode. By simply replacing water with an organic solvent (for example, N,N′-dimethyl formamide, DMF), the PAA binder is enriched locally in DMF because the PAA chains collapse in the DMF solution, leading to an increased functional group density. Improved electrochemical performance in terms of capacity retention and rate capacity is achieved by the locally enriched PAA binder in both half-cell and full-cell configurations. In detail, the SiOx/PAA-DMF‖Li half-cell exhibits a high reversible capacity with enhanced long-term cycling stability (1447 mA h g−1 at 0.5 C for over 100 cycles with 84.5% capacity retention). The LiFePO4‖SiOx full-cell test shows that the capacity retention is increased from 62.4% to 74.4% after 200 cycles at 0.5 C. This work establishes a new concept practically feasible for applications of the alloying-based lithium-ion battery anode. [ABSTRACT FROM AUTHOR]

Titanium dioxide of bronze phase (TiO2(B)) has attracted considerable attention as a promising alternative lithium/sodium‐ion battery anode due to its excellent operation safety, good reversible capacity, and environmental friendliness. However, several intrinsic critical drawbacks, including moderate electrochemical kinetics and unsatisfactory long cyclic stability, significantly limit its practical applications. It is crucial to develop reliable strategies to resolve these issues to advance the TiO2(B) based materials into practical applications in lithium/sodium‐ion batteries. In this review, both the theoretical and experimental investigations on the TiO2(B) based materials over the last few decades are chronically elaborated. Insights on the general and detailed evolution trends of the research on TiO2(B) anodes are provided. The review also points to future directions for the TiO2(B) anode research to advance the practical application of TiO2(B) anodes. [ABSTRACT FROM AUTHOR]

The LiCoO 2 (LCO) cathode is foreseen for extensive commercial applications owing to its high specific capacity and stability. Therefore, there is considerable interest in further enhancing its specific capacity by increasing the charging voltage. However, single-crystal LCO suffers from a significant capacity degradation when charged to 4.5 V due to the irreversible phase transition and unstable structure. Herein, an ultra-small amount (0.5% wt. in the electrode) of multi-functional PIM-1 (a polymer with intrinsic microporosity) additive is utilized to prepare a kind of binder-free electrode. PIM-1 modulates the solvation structure of LiPF 6 due to its unique structure, which helps to form a stable, robust, and inorganic-rich cathod-eelectrolyte interphase (CEI) film on the surface of LCO at a high voltage of 4.5 V. This reduces the irreversible phase transition of LCO, thereby enhancing the cyclic stability and improving the rate performance, providing new perspectives for the electrodes fabrication and improving LCO-based high-energy-density cathodes., (© 2024 The Authors. Small published by Wiley‐VCH GmbH.)