Lithium-ion batteries play a crucial role in storing energy for renewable sources and electric vehicles, yet face challenges related to insufficient energy density. Elevating the working-voltage of cathodes is promising to boost the energy density of batteries by increasing both the output voltage and capacity of cathode, which however could compromise life cycle and safety. This review provides a comprehensive summary of essential factors governing pathways of cathode-induced thermal runaway, including electrolyte decomposition, phase transitions, and crosstalk-induced reactions. Electrode and electrolyte modifications aimed at mitigating parasitic reactions and preventing crosstalk were also discussed. The review concludes with insights into the future application of these strategies, providing a comprehensive perspective on the realization of high-energy and safe batteries.

Low temperature aqueous batteries (LT-ABs) have attracted extensive attention recent years. The LT-ABs suffer from electrolyte freezing, slow ionic diffusion and sluggish interfacial redox kinetics at low temperature. In this review, we discuss physicochemical properties of aqueous electrolytes in terms of phase diagram, ion diffusion and interfacial redox kinetics to guide the design of low temperature aqueous electrolytes (LT-AEs). Firstly, the characteristics of equilibrium and non-equilibrium phase diagrams are introduced to analyze the antifreezing mechanisms and propose design strategies for LT-AEs. Then, the temperature/concentration/charge carrier dependence conductivity characteristics in aqueous electrolytes are reviewed to comprehend and regulate the ion diffusion kinetics. Moreover, we introduce interfacial studies in aqueous and non-aqueous batteries and propose potential improvement strategies for interfacial redox kinetics in LT-ABs. Finally, we summarize design strategies of LT-AEs for developing high performance LT-ABs.