Lithium metal and lithium-rich alloys are high-capacity anode materials that could boost the energy content of rechargeable batteries. However, their development has been hindered by rapid capacity decay during cycling, which is driven by the substantial structural, morphological, and volumetric transformations that these materials and their interfaces experience during charge and discharge. During these transformations, the interplay between chemical/structural changes and solid mechanics plays a defining role in determining electrochemical degradation. This Perspective discusses how chemistry and mechanics are interrelated in influencing the reaction mechanisms, stability, and performance of both lithium metal anodes and alloy anodes. Battery systems with liquid electrolytes and solid-state electrolytes are considered because of the distinct effects of chemo-mechanics in each system. Building on this knowledge, we present a discussion of emerging ideas to control and mitigate chemo-mechanical degradation in these materials to enable translation to commercial systems, which could lead to the development of high-energy batteries that are urgently needed to power our increasingly electrified world.
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Toward Practical Alloy Anode Based Solid State Batteries
Alloy‐based anodes are regarded as safer and higher capacity alternatives to lithium metal and commercial graphite anodes respectively. However, their commercialization is hindered by poor stability and irreversible loss of active material during cycling. Combining non‐flammable and electrochemically stable solid‐state electrolytes with high‐capacity alloy anodes has chemo‐mechanical benefits that can address these long‐standing issues. The distinctive interfacial characteristics of solid‐state electrolytes reduce the impact of volume variation and dynamic reconstruction of the solid‐electrolyte‐interphase, thereby realizing the best of both worlds. In this perspective, the interfacial underpinnings for alloy anode based solid‐state batteries that are crucial for their success are discussed. The goal is to update the audience with key recent findings that can lay the foundation for future research work in this area. The relevant steps toward commercialization of alloy anode based solid‐state batteries are also discussed, starting from bulk and interface architectures to electrode composite preparation and final cell assembly.
more » « less- PAR ID:
- 10480410
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small
- ISSN:
- 1613-6810
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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