Research on performance constraints and electrolyte optimization strategies for lithium-ion batteries at low...

Lithium-ion batteries (LIBs) are extensively utilized in electronic devices, electric vehicles, and energy storage systems to meet the growing energy demand, due to their high energy density, extended lifespan, and absence of the memory effect. However, their high performance is significantly diminished at low temperatures. Recent research indicates that the low-temperature performance of LIBs is constrained by the sluggish diffusion of Li⁺ in the electrolyte, across the interfaces, and within the electrodes. At lower temperatures, the rise in electrolyte viscosity results in a slower ion transport rate, which is a key factor affecting battery performance. The electrolyte primarily consists of lithium salts, solvents, and additives, and improvements in these three aspects are crucial for the creation of electrolytes with excellent low-temperature performance. This review systematically introduces the factors responsible for the decline in LIBs performance at low temperatures, including reduced ionic conductivity in the electrolyte, increased Li⁺ desolvation energy in the electrolyte, slow transfer kinetics at the interface, on the anode significant lithium plating and dendrite formation, and slow Li⁺ diffusion within the electrode material. Advancements in research on lithium salts, solvents, additives, and novel electrolytes are methodically presented, comprising localized high-concentration electrolytes, weakly solvating electrolytes, liquefied gas electrolytes, and polymer electrolytes. Finally, the challenges that must be addressed in current low-temperature LIBs are identified, and potential future developments in this field are anticipated.