Introduction to next-generation battery technologies beyond lithium

Li-ion batteries have represented a major breakthrough in the portability of electronic devices and have enabled the development of electric vehicles and new wireless technologies (e.g., wearables, gadgets, trackers), which have significantly improved our daily lives. Their importance was underscored by the awarding of the Nobel Prize in Chemistry in 2019 to Dr Yoshino, Prof. Whittingham, and Prof. Goodenough.

The energy storage market is experiencing rapid growth, but the geographic concentration of lithium resources poses several vulnerabilities for the power sector, including supply-chain issues, costs, and geopolitical risks. Generally, non-lithium-ion energy storage systems tend to have lower energy density because they use heavier charge carriers, such as sodium (Na⁺), potassium (K⁺), magnesium (Mg²⁺), zinc (Zn²⁺), and aluminum (Al³⁺), instead of lithium. However, exploring non-lithium-ion chemistries that diversify the raw materials and processing methods can help mitigate these risks and broaden options for energy storage systems across various applications. Currently, a wide range of new battery chemistries, including recently commercialized sodium-based batteries and multivalent systems, are being actively investigated, with particular attention to safety, cost, sustainability and manufacturability.

As with the development of Li-ion batteries, the success of emerging battery technologies depends on interdisciplinary collaboration across electrochemistry, materials science, engineering, and physics. Progress at the cell level requires addressing all components – from active materials and electrolytes to often-overlooked elements such as binders and separators.

This themed collection in Sustainable Energy & Fuels is intended to bring together the latest research efforts in advancing battery technologies beyond lithium, covering a diversity of battery chemistries including sodium–sulfur (https://doi.org/10.1039/D5SE00531K), aluminum–CO₂ (https://doi.org/10.1039/D5SE00608B), redox-flow (https://doi.org/10.1039/D5SE00844A), chloride-ion (https://doi.org/10.1039/D5SE00298B) and zinc-ion batteries (https://doi.org/10.1039/D5SE00939A). In addition, improving the design of the electrode materials – such as cathodes in sodium-ion batteries (https://doi.org/10.1039/D4SE01730G) – and investigating the potential of alternative electrodes for different battery chemistries (https://doi.org/10.1039/D5SE00193E) are essential. Post-lithium-metal batteries have attracted significant attention for their high energy density, though they face multiple challenges related to anode stability. In this sense, the modification of the solid electrolyte interface can be an effective strategy to enhance the stability of the metal: https://doi.org/10.1039/D5SE00307E.

The use of binders in the electrode formulation can play a critical role in the electrochemical performance. The employment of alternative but also more sustainable biopolymer binders is preferred (https://doi.org/10.1039/D5SE00939A). Ultimately, solid-state batteries are emerging as one of the next-generation energy storage technologies due to their higher energy density, safety, and thermal stability, with solid-state electrolytes (SSEs) being critical to their performance. Therefore, the modification of this cell component is also discussed in this themed collection (https://doi.org/10.1039/D5SE00285K).

Acknowledgements

M. Sevilla thanks IDE/2024/000792 (FICYT/FEDER) and PID2024-157261OB-I00 (MICIU/AEI/10.13039/501100011033/FEDER, UE). G. A. Ferrero thanks the Federal Ministry of Education and Research (BMBF) (SIB:DE, 03XP0627C).

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