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  • Perspective
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Addressing the safety of next-generation batteries

Nature volume 645, pages 603–613 (2025)Cite this article

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Abstract

Owing to increasing demand for low-cost energy storage with secure material supply chains, the battery community is approaching a pivotal shift beyond conventional lithium-ion (Li-ion) towards next-generation cells. Technologies that include alkali-metal anodes, solid electrolytes and earth-abundant materials such as sodium (Na) and sulfur (S) are reaching commercialization in cells. The abuse tolerance and thermal runaway hazards of such technologies diverge from conventional Li-ion cells. Consequently, designing safe batteries with next-generation materials requires a holistic approach to characterize cells and to understand their responses to abuse conditions from the beginning to the end of life. Here we provide a Perspective on how the safety and abuse tolerance of cells are likely to change for up-and-coming technologies; challenges and opportunities for reimagining safe cell and battery designs; gaps in our knowledge; capabilities for understanding the hazards of thermal runaway and how to address them; how standard abuse tests may need to adapt to new challenges; and how research needs to support affected professionals, from pack designers to first responders, to manage hazards and ensure safe roll-out of next-generation cells into applications like electric vehicles (EVs). Finally, given the large number of next-generation technologies being explored, we encourage giving priority to safety-focused research in proportion to the rate of manufacturing scale-up of each specific technology.

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Fig. 1: A detailed experimental campaign to evaluate the safety of next-generation battery cells.
Fig. 2: Stages of thermal runaway under thermal abuse conditions.
Fig. 3: Impact of ageing history on safety and abuse tolerance of batteries.
Fig. 4: Multiscale approach for enhanced safety reliability of batteries.

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Acknowledgements

This work is authored in part by the National Renewable Energy Laboratory, operated by Alliance for Sustainable Energy, LLC, for the US Department of Energy (DOE) under contract no. DE- AC36-08GO28308. Financing is provided by the US DOE Advanced Research Projects Agency-Energy (ARPA-E) (award number DE-AR00001723, work authorization number 22/CJ000/07/03). We thank technology manager, H. Cheeseman for their support throughout this project. The views expressed in the article do not necessarily represent the views of the DOE or the US Government. The US Government and the publisher, by accepting the article for publication, acknowledges that the US Government retains a nonexclusive, paid-up, irrevocable, worldwide license to publish or reproduce the published form of this work, or allow others to do so, for US Government purposes.

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  1. These authors contributed equally: Chuanbo Yang, Avtar Singh, Donal P. Finegan

Authors and Affiliations

  1. National Renewable Energy Laboratory, Golden, CO, USA

    Chuanbo Yang, Avtar Singh, Xiaofei Pu, Anudeep Mallarapu, Kandler Smith, Matt Keyser & Donal P. Finegan

  2. Walker Department of Mechanical Engineering, The University of Texas at Austin, Austin, TX, USA

    Michael R. Haberman, Hadi Khani & Ofodike A. Ezekoye

  3. Materials Science and Engineering Program, Texas Materials Institute, The University of Texas at Austin, Austin, TX, USA

    Hadi Khani

  4. Maseeh Department of Civil, Architectural and Environmental Engineering, The University of Texas at Austin, Austin, TX, USA

    Pawel Misztal

  5. Exponent, Inc., Natick, MA, USA

    Ryan Spray

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Contributions

C.Y., A.S., X.P., A.M. and D.P.F. contributed to forming and writing the manuscript. K.S., M.K., O.A.E., M.R.H., H.K., P.M. and R.S. contributed to reviewing and editing the manuscript and providing feedback on the layout and important topics to discuss.

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Correspondence to Donal P. Finegan.

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Yang, C., Singh, A., Pu, X. et al. Addressing the safety of next-generation batteries. Nature 645, 603–613 (2025). https://doi.org/10.1038/s41586-025-09358-4

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