Using phenyl methanesulfonate as an electrolyte additive to improve performance of LiNi0.5Co0.2Mn0.3O2/graphite cells at low temperature

Unlocking Reversible Silicon Redox for High-Performing Chlorine Batteries

Chlorine (Cl)-based batteries such as Li/Cl2 batteries are recognized as promising candidates for energy storage with low cost and high performance. However, the current use of Li metal anodes in Cl-based batteries has raised serious concerns regarding safety, cost, and production complexity. More importantly, the well-documented parasitic reactions between Li metal and Cl-based electrolytes require a large excess of Li metal, which inevitably sacrifices the electrochemical performance of the full cell. Therefore, it is crucial but challenging to establish new anode chemistry, particularly with electrochemical reversibility, for Cl-based batteries. Here we show, for the first time, reversible Si redox in Cl-based batteries through efficient electrolyte dilution and anode/electrolyte interface passivation using 1,2-dichloroethane and cyclized polyacrylonitrile as key mediators. Our Si anode chemistry enables significantly increased cycling stability and shelf lives compared with conventional Li metal anodes. It also avoids the use of a large excess of anode materials, thus enabling the first rechargeable Cl2 full battery with remarkable energy and power densities of 809 Wh kg-1 and 4,277 W kg-1 , respectively. The Si anode chemistry affords fast kinetics with remarkable rate capability and low-temperature electrochemical performance, indicating its great potential in practical applications.

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.