Achieving Enhanced High-Temperature Performance of Lithium-Ion Batteries via Salt-Inspired Interfacial Engineering

Area of Science:

• Materials Science
• Electrochemistry
• Battery Technology

Background:

• High-energy lithium-ion batteries with Ni-rich cathodes (NCM) require stable interfacial layers for extended lifespan.
• Existing electrolyte additives often have limitations when used individually, necessitating synergistic combinations.
• Protecting both anode and cathode interfaces is crucial for overall battery performance and durability.

Purpose of the Study:

• To develop a novel multifunctional electrolyte additive, LiPENS, for advanced lithium-ion batteries.
• To investigate the synergistic effects of LiPENS combined with vinylene carbonate (VC) in protecting battery interfaces.
• To enhance the electrochemical performance and cycle life of high-energy NCM811 cathode batteries.

Main Methods:

• Synthesis and characterization of a molecular-engineered salt-type additive, LiPENS.
• Electrochemical testing of LiPENS and VC combination in NCM811/Gr full cells.
• Analysis of interfacial layer formation (SEI and CEI) using various techniques.

Main Results:

• LiPENS and VC combination effectively reinforced the solid electrolyte interphase (SEI) on the graphite anode, minimizing growth.
• An inorganic-rich cathode-electrolyte interface (CEI) was formed, mitigating phase transitions and mechanical degradation of NCM811.
• The full cell demonstrated a discharge capacity of 190.7 mAh g⁻¹ with 91.8% capacity retention after 300 cycles at 1 C and 45 °C.

Conclusions:

• The novel LiPENS additive, when paired with VC, offers a promising strategy for creating robust interfacial layers in high-energy lithium-ion batteries.
• This approach significantly improves battery cycle life and stability, addressing key limitations of current battery technologies.
• The development paves the way for more efficient, reliable, and commercially viable batteries for demanding applications like electric vehicles.