Since their commercialization by Sony in 1991, graphite anodes in combination with various cathodes have enabled the widespread success of lithium‐ion batteries (LIBs), providing over 10 billion rechargeable batteries to the global population. Next‐generation nonaqueous alkali metal‐ion batteries, namely sodium‐ion batteries (SIBs) and potassium‐ion batteries (PIBs), are projected to utilize intercalation‐based carbon anodes as well, due to their favorable electrochemical properties. While traditionally graphite anodes have dominated the market share of LIBs, other carbon materials have been investigated, including graphene, carbon nanotubes, and disordered carbons. The relationship between carbon material properties, electrochemical performance, and charge storage mechanisms is clarified for these alkali metal‐ion batteries, elucidating possible strategies for obtaining enhanced cycling stability, specific capacity, rate capability, and safety aspects. As a key component in determining cell performance, the solid electrolyte interphase layer is described in detail, particularly for its dependence on the carbon anode. Finally, battery safety at extreme temperatures is discussed, where carbon anodes are susceptible to dendrite formation, accelerated aging, and eventual thermal runaway. As society pushes toward higher energy density LIBs, this review aims to provide guidance toward the development of sustainable next‐generation SIBs and PIBs.
Lithium‐ion batteries (LIBs) show poor performance at temperatures below 0 °C due to sluggish reaction kinetics, hindered diffusion, and electrolyte freezing. Materials that alloy with lithium offer higher specific capacity than graphite anodes and are studied extensively at room temperature, but their low‐temperature behavior is not well understood. Here, the electrochemical and transformation behavior of three alloy materials (antimony, silicon, and tin) are investigated. It is shown that antimony is particularly well suited for low‐temperature applications due to its relatively high electrode potential and promising electrochemical stability at low temperatures. It is found that lithium‐antimony alloys can be cycled down to −40 °C with ten times higher specific capacity than graphite on the first cycle. The galvanostatic intermittent titration technique is used to understand the kinetic and thermodynamic limitations of these electrode materials at low temperatures, and X‐ray diffraction shows that electrochemical phase transformation behavior is also altered at low temperatures. Finally, it is found that the use of reference electrodes is necessary at low temperatures to avoid counter electrode effects. This investigative study provides new understanding of the behavior of alloy anodes at low temperatures and reveals the need for electrode/electrolyte optimization to enable low‐temperature LIBs.more » « less
- NSF-PAR ID:
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Advanced Energy Materials
- Medium: X
- Sponsoring Org:
- National Science Foundation
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This work was partially supported by the U.S. National Science Foundation (NSF) Award No. ECCS-1931088. S.L. and H.W.S. acknowledge the support from the Improvement of Measurement Standards and Technology for Mechanical Metrology (Grant No. 22011044) by KRISS.
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