Non-Flammable Electrolyte Enables High-Voltage and Wide-Temperature Lithium-Ion Batteries with Fast Charging.

Electrolyte design has become ever more important to enhance the performance of lithium-ion batteries (LIBs). However, the flammability issue and high reactivity of the conventional electrolytes remain a major problem, especially when the LIBs are operated at high voltage and extreme temperatures. Herein, we design a novel non-flammable fluorinated ester electrolyte that enables high cycling stability in wide-temperature variations (e.g., -50 °C-60 °C) and superior power capability (fast charge rates up to 5.0 C) for the graphite||LiNi _0.8 Co _0.1 Mn _0.1 O ₂ (NCM811) battery at high voltage (i.e., >4.3 V vs. Li/Li ⁺ ). Moreover, this work sheds new light on the dynamic evolution and interaction among the Li ⁺ , solvent, and anion at the molecular level. By elucidating the fundamental relationship between the Li ⁺ solvation structure and electrochemical performance, we can facilitate the development of high-safety and high-energy-density batteries operating in harsh conditions.
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