2D MXene Anodes with Engineered Electrolyte for High-Performing Lithium-Ion Batteries in Extreme Cold

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Lithium-ion batteries (LIBs) exhibit significant performance degradation at subzero temperatures.
• This degradation is caused by slow ion diffusion, increased resistance, and electrolyte freezing.
• Conventional graphite anodes are particularly limited in cold environments.

Purpose of the Study:

• To investigate titanium carbide (Ti3C2Tx) MXene as a novel anode material for low-temperature LIBs.
• To overcome the limitations of traditional anode materials in subzero conditions.
• To demonstrate functional LIB operation at extremely low temperatures.

Main Methods:

• Electrochemical characterization of Ti3C2Tx MXene and graphite electrodes.
• Utilizing a dipropyl ether (DPE)-based lithium bis(fluorosulfonyl)imide (LiFSI) electrolyte.
• Density Functional Theory (DFT) calculations to elucidate ion transport mechanisms.

Main Results:

• Ti3C2Tx MXene anodes showed significantly lower charge-transfer resistance compared to graphite.
• Exceptional low-temperature performance: 31.7 mAh g-1 at -70°C for Ti3C2Tx MXene.
• Graphite anodes exhibited negligible capacity at -50°C.
• The DPE-based electrolyte maintained substantial ionic conductivity at -10°C.
• Stable electrochemical performance achieved in extreme cold conditions.

Conclusions:

• Ti3C2Tx MXene's properties, including high conductivity and pseudocapacitance, enable efficient Li+ transport at low temperatures.
• The combination of Ti3C2Tx MXene anodes and DPE-based electrolytes allows LIBs to operate down to -70°C.
• This study highlights Ti3C2Tx MXene as a promising next-generation anode material for extreme-temperature applications.