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A robust all-organic protective layer towards ultrahigh-rate and large-capacity Li metal anodes

Nature Nanotechnology volume 17, pages 613–621 (2022)Cite this article

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Abstract

The low cycling efficiency and uncontrolled dendrite growth resulting from an unstable and heterogeneous lithium–electrolyte interface have largely hindered the practical application of lithium metal batteries. In this study, a robust all-organic interfacial protective layer has been developed to achieve a highly efficient and dendrite-free lithium metal anode by the rational integration of porous polymer-based molecular brushes (poly(oligo(ethylene glycol) methyl ether methacrylate)-grafted, hypercrosslinked poly(4‐chloromethylstyrene) nanospheres, denoted as xPCMS-g-PEGMA) with single-ion-conductive lithiated Nafion. The porous xPCMS inner cores with rigid hypercrosslinked skeletons substantially increase mechanical robustness and provide adequate channels for rapid ionic conduction, while the flexible PEGMA and lithiated Nafion polymers enable the formation of a structurally stable artificial protective layer with uniform Li+ diffusion and high Li+ transference number. With such artificial solid electrolyte interphases, ultralong-term stable cycling at an ultrahigh current density of 10 mA cm−2 for over 9,100 h (>1 year) and unprecedented reversible lithium plating/stripping (over 2,800 h) at a large areal capacity (10 mAh cm−2) have been achieved for lithium metal anodes. Moreover, the protected anodes also show excellent cell stability when paired with high-loading cathodes (~4 mAh cm−2), demonstrating great prospects for the practical application of lithium metal batteries.

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Fig. 1: Schematic illustrations of structure and Li plating behaviour for artificial SEI layers.
Fig. 2: Characterization of artificial protective layers.
Fig. 3: Electrochemical performance of Li metal anodes.
Fig. 4: Electrochemical performance of symmetric Li|Li cells.
Fig. 5: In operando observation of Li deposition.
Fig. 6: Electrochemical performance of Li|LFP coin cells.

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Data availability

All data generated in this study are included in the published article and its Supplementary Information.

Change history

  • 06 May 2022

    In the version of this article initially published, the scale bars shown in Fig. 2b,c and Fig. 6h were made proportionally incorrect during publisher processing, and have now been resized.

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Acknowledgements

This work was supported by the National Natural Science Foundation of China (51925308 and 51872336), the National Key Research and Development Program of China (2021YFF0500600), the Leading Scientific, Technical and Innovation Talents of the Guangdong Special Support Program (2017TX04C248), the Pearl River Talent Plan of Guangdong (2017GC010612), the Natural Science Foundation of Guangdong (2021A1515011617), the Fundamental Research Funds for the Central Universities (20lgzd18) and the Science and Technology Program of Guangzhou (202102021111 and 202002020041).

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Authors and Affiliations

  1. PCFM Lab and GDHPRC Lab, School of Chemistry, Sun Yat-sen University, Guangzhou, People’s Republic of China

    Shimei Li, Junlong Huang, Yin Cui, Shaohong Liu, Zirun Chen, Wen Huang, Chuanfa Li, Ruliang Liu, Ruowen Fu & Dingcai Wu

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  1. Shimei Li
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Contributions

D.W. conceived the concept and supervised the research. S. Liu and D.W. designed the project. S. Li synthesized the materials. S. Li, J.H., Y.C., Z.C., W.H. and C.L. performed the material characterization and electrochemical tests. S. Li, S. Liu and D.W. wrote the manuscript. R.L. and R.F. gave advice on the research. All authors discussed the results and commented on the manuscript.

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Correspondence to Shaohong Liu or Dingcai Wu.

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Nature Nanotechnology thanks Qiang Zhang and the other, anonymous, reviewer(s) for their contribution to the peer review of this work.

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Supplementary information

Supplementary Information

Supplementary Figs. 1–31 and Table 1.

Supplementary Video 1

In operando observation of Li deposition on bare Li.

Supplementary Video 2

In operando observation of Li deposition on the xPCMS-g-PEGMA/LN@Li anode.

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Li, S., Huang, J., Cui, Y. et al. A robust all-organic protective layer towards ultrahigh-rate and large-capacity Li metal anodes. Nat. Nanotechnol. 17, 613–621 (2022). https://doi.org/10.1038/s41565-022-01107-2

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