High-Temperature Long-Term Cycling Capability of Lithium Batteries Enabled by Releasing Local Constriction

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• High-temperature secondary battery technology is crucial for space exploration and commercial spaceflight.
• Metal/semimetal anodes, while offering high capacity, suffer from high-temperature creep, compromising safety and performance.
• Anode degradation in high-temperature batteries is linked to the formation of unstable Li-rich phases due to interfacial issues.

Purpose of the Study:

• To identify the degradation mechanism in high-temperature batteries.
• To design a novel heat-resistant anode for improved high-temperature performance and safety.
• To demonstrate the capabilities of solid-state batteries with the designed anode.

Main Methods:

• Investigated anode degradation mechanisms in high-temperature batteries.
• Designed a heat-resistant anode with a Zintl-like phase core and a conformal coating.
• Assembled and tested solid-state batteries (SSBs) with the novel anode under various temperature conditions.

Main Results:

• Identified Li-rich phase generation at anodes as a key degradation pathway.
• Developed a heat-resistant anode that mitigates interfacial constriction and deactivation.
• Achieved stable cycling of over 1,000 cycles at 120°C (2C) with a 340 Wh kg⁻¹ SSB.
• Demonstrated outstanding temperature adaptability from -40°C to 150°C.

Conclusions:

• The designed anode effectively suppresses high-temperature degradation in solid-state batteries.
• This technology offers a promising solution for reliable high-temperature energy storage in demanding applications.
• The SSB exhibits superior thermal stability compared to traditional molten salt high-temperature batteries.