The low temperature electrochemical performances of LiFePO 4 /C/graphene nanofiber with 3D-bridge network structure

Lithium-Ion Batteries under Low-Temperature Environment: Challenges and Prospects

Lithium-ion batteries (LIBs) are at the forefront of energy storage and highly demanded in consumer electronics due to their high energy density, long battery life, and great flexibility. However, LIBs usually suffer from obvious capacity reduction, security problems, and a sharp decline in cycle life under low temperatures, especially below 0 °C, which can be mainly ascribed to the decrease in Li⁺ diffusion coefficient in both electrodes and electrolyte, poor transfer kinetics on the interphase, high Li⁺ desolvation barrier in the electrolyte, and severe Li plating and dendrite. Targeting such issues, approaches to improve the kinetics and stability of cathodes are also dissected, followed by the evaluation of the application prospects and modifications between various anodes and the strategies of electrolyte design including cosolvent, blended Li salts, high-concentration electrolyte, and additive introduction. Such designs elucidate the successful exploration of low-temperature LIBs with high energy density and long lifespan. This review prospects the future paths of research for LIBs under cold environments, aiming to provide insightful guidance for the reasonable design of LIBs under low temperature, accelerating their widespread application and commercialization.

Constructing Robust Cathode/Electrolyte Interphase for Ultrastable 4.6 V LiCoO2 under -25 °C

Improving the durability of cathode materials at low temperature is of great importance for the development nowadays of lithium ion batteries, since the practical capacity and cycling stability of the electrode are reduced significantly at low temperature. Herein, by amorphous Zr₃(PO₄)₄ surface engineering, we realize a stable high-voltage LiCoO₂ operation (4.6 V) at -25 °C. The highly amorphous surface layer can help to form a high-quality cathode-electrolyte interphase with strong stability and low interface resistance, especially at low temperature. Such a surface-engineered LiCoO₂ shows a capacity of 179.2 mAh g^-1 at 0.2C and an excellent cyclability with 91% capacity retention after 300 cycles (1C). As a comparison, bare LiCoO₂ shows only 161.6 mAh g^-1 and 1% capacity retention under the same circumstances. This work confirms that surface regulation and control engineering is an effective route to improve the high-voltage and low-temperature performance of LiCoO₂.

Critical Review on Low-Temperature Li-Ion/Metal Batteries

With the highest energy density ever among all sorts of commercialized rechargeable batteries, Li-ion batteries (LIBs) have stimulated an upsurge utilization in 3C devices, electric vehicles, and stationary energy-storage systems. However, a high performance of commercial LIBs based on ethylene carbonate electrolytes and graphite anodes can only be achieved at above -20 °C, which restricts their applications in harsh environments. Here, a comprehensive research progress and in-depth understanding of the critical factors leading to the poor low-temperature performance of LIBs is provided; the distinctive challenges on the anodes, electrolytes, cathodes, and electrolyte-electrodes interphases are sorted out, with a special focus on Li-ion transport mechanism therein. Finally, promising strategies and solutions for improving low-temperature performance are highlighted to maximize the working-temperature range of the next-generation high-energy Li-ion/metal batteries.

Microstructure and electrochemical performance of LiFePO4 cathode materials modified with binuclear metal aminophthalocyanines

The monodispersed LiFe[Formula: see text]M[Formula: see text]PO4/C [[Formula: see text] [Formula: see text] 0.0040; [Formula: see text] = Mn[Formula: see text], Co[Formula: see text], Ni[Formula: see text], Cu[Formula: see text], Zn[Formula: see text]] nanocomposites obtained by LiFePO4 modified with binuclear metal aminophthalocyanines (M2(PcTa)2O and M2(PcTa)2C(CF[Formula: see text] are utilized as positive electrode materials for lithium ion batteries. The preparation method for these nanocomposites is a controllable solvothermal method using a mixture of ethylene glycol and [Formula: see text],[Formula: see text]-dimethylformamide as the solvent. The microstructure and electrochemical properties of the different nanocomposites are discussed and compared. The results show that the LiFePO4 samples modified with M2(PcTa)2C(CF[Formula: see text]can improve the initial discharge specific capacity of the lithium ion battery up to 154.2 mAh.g[Formula: see text]at the rate of 0.1 C, and 93.5% of the initial discharge capacity could be retained after 50 cycles. This research shows that the proposed process can enhance the electrochemical performance of high power LiFePO4 for lithium ion batteries.