Thermocells (also called thermo-electrochemical cells) are a promising technology for converting low-grade heat (<200°C) into electricity through temperature-dependent redox reactions and/or ion diffusion. Very recently, there have been several breakthroughs in thermocells regarding Seebeck coefficients up to 34 mVK^–1 and efficiencies up to 11% by optimizing thermo-electrochemical processes. Proof-of-concept devices can obtain a power output on the order of 100 mW by harvesting ambient body heat or solar energy, which are effective power sources for various electronic devices. The rapid pace of advances in this field, however, also trigger rigorous controversies, including volatility, low power density, and the degradation of redox couples. Herein, we provide a holistic discussion on the current-state knowledge for improving thermocell performance and examine a few state-of-the-art engineering strategies for broadening the application of thermocells.

热电池（也称为热电化学电池）是一种很有前景的技术，可通过依赖于温度的氧化还原反应和/或离子扩散将低级热量（<200°C）转化为电能。最近，热电池在塞贝克系数高达 34 mVK ^–1方面取得了多项突破通过优化热电化学过程，效率高达 11%。概念验证设备可以通过收集环境体热或太阳能获得 100 mW 数量级的功率输出，这些是各种电子设备的有效电源。然而，该领域的快速进步也引发了激烈的争议，包括挥发性、低功率密度和氧化还原对的退化。在此，我们全面讨论了用于提高热电偶性能的当前知识，并研究了一些最先进的工程策略，以扩大热电偶的应用。