Materials design and fundamental understanding of tellurium-based electrochemistry for rechargeable batteries

Rechargeable tellurium (Te)-based batteries are emerging as energy storage devices with high volumetric energy density due to tellurium's superior electronic conductivity and high specific volumetric capacity. However, Te-based batteries are quite new, raising fundamental questions regarding the electrochemistry of Te-based cathodes and holistic aspects of full-cell performance. This review begins with a critical discussion on Li-Te electrochemistry in carbonate and ether electrolytes, followed by a comprehensive review on material design, cell architectures, and the working mechanism of Te-based cathodes in Li-Te-based batteries. The primary focus is to develop a fundamental understanding of the Te structure's role, carbon host chemistry and porosity, and the use of electrolytes to address Te pulverization and parasitic polytellurides shuttle effects and to establish reversible Te and Li2Te phase transitions. In addition, liquid and solid-state electrolytes for Li-Te batteries showing promise of enabling a stable solid electrolyte interphase (SEI) and reversible Te cathode reactions are presented. The following section exemplifies other novel metal-Te based batteries, including Na-Te, K-Te, Mg-Te, Zn-Te, and Al-Te systems, highlighting their respective cathode and electrolyte selection. Then, the comparison of quantitative performance data of various metal-Te-based batteries across Li-ion and Li-S batteries is revealed to provide a landscape of current research. In closing, this work identifies unanswered scientific and technological questions, discusses promising research directions, and highlights the experimental and simulation-based studies needed to discover the unknown of rechargeable Te-based batteries.