Lithium whisker growth and stress generation in an in situ atomic force microscope–environmental transmission electron microscope set-up

Abstract

Lithium metal is considered the ultimate anode material for future rechargeable batteries1,2, but the development of Li metal-based rechargeable batteries has achieved only limited success due to uncontrollable Li dendrite growth3,4,5,6,7. In a broad class of all-solid-state Li batteries, one approach to suppress Li dendrite growth has been the use of mechanically stiff solid electrolytes8,9. However, Li dendrites still grow through them10,11. Resolving this issue requires a fundamental understanding of the growth and associated electro-chemo-mechanical behaviour of Li dendrites. Here, we report in situ growth observation and stress measurement of individual Li whiskers, the primary Li dendrite morphologies12. We combine an atomic force microscope with an environmental transmission electron microscope in a novel experimental set-up. At room temperature, a submicrometre whisker grows under an applied voltage (overpotential) against the atomic force microscope tip, generating a growth stress up to 130 MPa; this value is substantially higher than the stresses previously reported for bulk13 and micrometre-sized Li14. The measured yield strength of Li whiskers under pure mechanical loading reaches as high as 244 MPa. Our results provide quantitative benchmarks for the design of Li dendrite growth suppression strategies in all-solid-state batteries.

Access options

Rent or Buy article

Get time limited or full article access on ReadCube.

from$8.99

All prices are NET prices.

Fig. 1: In situ AFM–ETEM characterization of stress generation during Li whisker growth.
Fig. 2: In situ AFM–ETEM imaging of Li whisker growth and concurrent measurement of the maximum stress in Li whiskers under applied voltages.
Fig. 3: In situ compression testing of as-grown Li whiskers.

References

  1. 1.

    Tarascon, J. M. & Armand, M. Issues and challenges facing rechargeable lithium batteries. Nature 414, 359–367 (2001).

  2. 2.

    Xu, W. et al. Lithium metal anodes for rechargeable batteries. Energy Environ. Sci. 7, 513–537 (2014).

  3. 3.

    Kushima, A. et al. Liquid cell transmission electron microscopy observation of lithium metal growth and dissolution: root growth, dead lithium and lithium flotsams. Nano Energy 32, 271–279 (2017).

  4. 4.

    Lin, D., Liu, Y. & Cui, Y. Reviving the lithium metal anode for high-energy batteries. Nat. Nanotechnol. 12, 194 (2017).

  5. 5.

    Guo, Y., Li, H. & Zhai, T. Reviving lithium-metal anodes for next-generation high-energy batteries. Adv. Mater. 29, 1700007 (2017).

  6. 6.

    Wang, X. et al. Stress-driven lithium dendrite growth mechanism and dendrite mitigation by electroplating on soft substrates. Nat. Energy 3, 227–235 (2018).

  7. 7.

    Li, L. et al. Self-heating–induced healing of lithium dendrites. Science 359, 1513–1516 (2018).

  8. 8.

    Liu, Y. et al. Making Li-metal electrodes rechargeable by controlling the dendrite growth direction. Nat. Energy 2, 17083 (2017).

  9. 9.

    Monroe, C. & Newman, J. The impact of elastic deformation on deposition kinetics at lithium/polymer interfaces. J. Electrochem. Soc. 152, A396–A404 (2005).

  10. 10.

    Ren, Y., Shen, Y., Lin, Y. & Nan, C. W. Direct observation of lithium dendrites inside garnet-type lithium-ion solid electrolyte. Electrochem. Commun. 57, 27–30 (2015).

  11. 11.

    Suzuki, Y. et al. Transparent cubic garnet-type solid electrolyte of Al2O3-doped Li7La3Zr2O12. Solid State Ion. 278, 172–176 (2015).

  12. 12.

    Brenner, S. S. Growth and properties of ‘whiskers’: further research is needed to show why crystal filaments are many times as strong as large crystals. Science 128, 569–575 (1958).

  13. 13.

    Schultz, R. P. Lithium: Measurement of Young’s Modulus and Yield Strength (Fermi National Accelerator Laboratory, 2002).

  14. 14.

    Xu, C., Ahmad, Z., Aryanfar, A., Viswanathan, V. & Greer, J. R. Enhanced strength and temperature dependence of mechanical properties of Li at small scales and its implications for Li metal anodes. Proc. Natl Acad. Sci. USA 114, 57–61 (2017).

  15. 15.

    Yang, T. T. et al. Air-stable lithium spheres produced by electrochemical plating. Angew. Chem. Int. Ed. Engl. 57, 12750–12753 (2018).

  16. 16.

    Li, L., Li, S. & Lu, Y. Suppression of dendritic lithium growth in lithium metal-based batteries. Chem. Commun. 54, 6648–6661 (2018).

  17. 17.

    Qian, J. et al. Dendrite-free Li deposition using trace-amounts of water as an electrolyte additive. Nano Energy 15, 135–144 (2015).

  18. 18.

    Porz, L. et al. Mechanism of lithium metal penetration through inorganic solid electrolytes. Adv. Energy Mater. 7, 1701003 (2017).

  19. 19.

    Xiang, B., Wang, L., Liu, G. & Minor, A. M. Electromechanical probing of Li/Li2CO3 core/shell particles in a TEM. J. Electrochem. Soc. 160, A415–A419 (2013).

  20. 20.

    Greer, J. R. & De Hosson, J. T. M. Plasticity in small-sized metallic systems: intrinsic versus extrinsic size effect. Prog. Mater. Sci. 56, 654–724 (2011).

  21. 21.

    Khan, A. S. & Huang, S. Continuum Theory of Plasticity (John Wiley & Sons, 1995).

  22. 22.

    Masias, A., Felten, N., Garcia-Mendez, R., Wolfenstine, J. & Sakamoto, J. Elastic, plastic, and creep mechanical properties of lithium metal. J. Mater. Sci. 54, 2585–2600 (2019).

  23. 23.

    Bridgman, P. W. The effect of tension on the electrical resistance of certain abnormal metals. Proc. Natl Acad. Sci. USA 57, 41–66 (1922).

  24. 24.

    Robertson, W. M. & Montgomery, D. J. Elastic modulus of isotopically-concentrated lithium. Phys. Rev. 117, 440–442 (1959).

  25. 25.

    Tariq, S.et al. Li material testing–Fermilab antiproton source lithium collection lens. In Proc. 2003 Particle Accelerator Conference (eds Chew, J. et al.) 1452–1454 (IEEE, 2003).

  26. 26.

    Ni, J. E., Case, E. D., Sakamoto, J. S., Rangasamy, E. & Wolfenstine, J. B. Room temperature elastic moduli and Vickers hardness of hot-pressed LLZO cubic garnet. J. Mater. Sci. 47, 7978–7985 (2012).

  27. 27.

    Wolfenstine, J. et al. A preliminary investigation of fracture toughness of Li7La3Zr2O12 and its comparison to other solid Li-ion conductors. Mater. Lett. 96, 117–120 (2013).

  28. 28.

    Ferrese, A. & Newman, J. Mechanical deformation of a lithium-metal anode due to a very stiff separator. J. Electrochem. Soc. 161, A1350–A1359 (2014).

  29. 29.

    Nagao, M. et al. In situ SEM study of a lithium deposition and dissolution mechanism in a bulk-type solid-state cell with a Li2S-P2S5 solid electrolyte. Phys. Chem. Chem. Phys. 15, 18600–18606 (2013).

  30. 30.

    Ansell, R. The chemical and electrochemical stability of beta-alumina. J. Mater. Sci. 21, 365–379 (1986).

  31. 31.

    He, Y. et al. Origin of lithium whisker formation and growth under stress. Nat. Nanotechnol. 14, 1042–1047 (2019).

  32. 32.

    Bai, P. et al. Interactions between lithium growths and nanoporous ceramic separators. Joule 2, 2434–2449 (2018).

  33. 33.

    Yulaev, A. et al. From microparticles to nanowires and back: radical transformations in plated Li metal morphology revealed via in situ scanning electron microscopy. Nano Lett. 18, 1644–1650 (2018).

Download references

Acknowledgements

This work was financially supported by the National Key Research and Development Programme of China (nos. 2018YFB0104300, 2017YFB0702001), Beijing Natural Science Foundation of China-Haidian Special Project (L182065), the National Natural Science Foundation of China (nos. 51971245, 51772262, 21406191, 21935009, 11575154, 21777177, 51971194), Natural Science Foundation of Hebei Province (no. B2018203297), Hebei One Hundred Talent Programme (grant no. 4570028), Youth Top-notch Talent Support Programme of Higher Education in Hebei Province (no. BJ2016053) and High-Level Talents Research Programme of the Yanshan University (nos. 00500021502, 005000201). We thank Z. Shan, Y. Wang, P. Li, H. Yang and C. Li for their support with the compression experiments.

Author information

L.Z., T.Y. and C.D. conceived the experiment. Q.L., Yushu Tang and J.Z. performed ETEM measurements. Y.S., P.J. and H.L. fabricated the AFM device. L.G., J.C. and H.Y. fabricated the carbon nanotube. Z.W., Y.L., H.S., X.L. and Q.D. conducted mechanical measurements. B.W. and T.C. performed computational modelling. Q.P., T.S., Yo Tang, S.Z., T.Z. and J.H. supervised the project. L.Z., T.Z. and J.H. wrote the paper. All authors discussed the results and commented on the manuscript.

Correspondence to Yongfu Tang or Sulin Zhang or Ting Zhu or Jianyu Huang.

Ethics declarations

Competing interests

The authors declare no competing interests.

Additional information

Publisher’s note Springer Nature remains neutral with regard to jurisdictional claims in published maps and institutional affiliations.

Supplementary information

Supplementary Information

Supplementary methods and discussion, Videos 1–19 and Figs. 1–34.

Supplementary Video 1

An in situ TEM movie showing the growth of a Li whisker (corresponding to Fig. 1d). As a negative potential was applied to the CNT against Li, a single Li spheroid started to nucleate at the contact point between the CNT and the Li2CO3 on the surface of the Li metal and then grew along the CNT, pushing the AFM cantilever upward. As the Li ball grew to about 1.26 μm in size, a whisker emerged underneath the ball which pushed the AFM cantilever up, thus generating the axially compressive stress in the whisker. When the whisker reached 4.08 μm in length, it collapsed due to the compression by the AFM tip. The attachment of a CNT to the AFM tip rendered controllable whisker nucleation. The movie was recorded at 5 frames per second in the bright field (BF) mode, and played at 97× speed (during ball generation) and 49× speed (during Li whisker generation).

Supplementary Video 2

An in situ TEM movie showing the growth of a Li whisker (corresponding to Supplementary Fig. 3). The Li whisker grows directly underneath the AFM cantilever without the prior formation of Li balls. The movie was recorded at 5 frames per second in BF mode, and played at 5× speed.

Supplementary Video 3

A Li whisker grows directly underneath the AFM cantilever (corresponding to Supplementary Fig. 4). A Li ball grows before the growth of a whisker. The movie was recorded at 5 frames per second in BF mode, and played at 212× speed (during ball generation) and 157× speed (during Li whisker generation).

Supplementary Video 4

A Li whisker grows directly underneath the AFM cantilever (corresponding to Supplementary Fig. 5). The movie was recorded at 5 frames per second in the BF mode, and played at 61× speed (during ball generation) and 44× speed (during Li whisker generation).

Supplementary Video 5

An in situ TEM movie showing the growth of a Li whisker underneath the AFM cantilever (corresponding to Supplementary Fig. 6). The whisker buckles after reaching a length of 1.90 μm. The movie was recorded at 5 frames per second in BF mode, and played at 13× speed (during ball generation) and 10× speed (during Li whisker generation).

Supplementary Video 6

An in situ TEM movie showing the growth of a Li whisker underneath the AFM cantilever (corresponding to Supplementary Fig. 7). The movie was recorded at 5 frames per second in BF mode, and played at 8× speed.

Supplementary Video 7

An in situ TEM movie showing the growth of a Li whisker underneath the AFM cantilever (corresponding to Supplementary Fig. 8). The movie was recorded at 5 frames per second in BF mode, and played at 184× speed.

Supplementary Video 8

An in situ TEM movie showing the growth of a Li whisker with <001> orientation (corresponding to Supplementary Fig. 12). A Li ball forms before the whisker growth. The movie was recorded at 5 frames per second in BF mode, and played at 188×speed (during ball generation) and 156× speed (during Li whisker generation).

Supplementary Video 9

An in situ TEM movie showing the growth of a Li whisker with <112> orientation (corresponding to Supplementary Fig. 13). The movie was recorded at 5 frames per second in BF mode, and played at 15× speed.

Supplementary Video 10

An in situ TEM movie showing the growth of a Li whisker with <110> orientation (corresponding to Supplementary Fig. 14). The movie was recorded at 5 frames per second in BF mode, and played at 31× speed (during ball generation) and 22× speed (during Li whisker generation).

Supplementary Video 11

An in situ TEM movie showing the growth of a Li whisker with <111> orientation (corresponding to Supplementary Fig. 15). The movie was recorded at 5 frames per second in BF mode, and played at 51× speed.

Supplementary Video 12

An in situ TEM movie showing the growth of a Li ball at the CNT and Li2CO3 contact point (corresponding to Supplementary Fig. 16). The movie was recorded at 5 frames per second in BF mode, and played at 201× speed.

Supplementary Video 13

An in situ TEM movie showing the generation of a Li whisker (corresponding to Fig. 2a). A faceted Li nanocrystal formed before the formation of a Li whisker. The movie was recorded at 5 frames per second in BF mode, and played at 46× speed (during ball generation) and 25× speed (during Li whisker generation).

Supplementary Video 14

An in situ TEM movie showing the growth of a Li whisker. To explore the relationship between the applied voltage and the growth stress, the potential was ramped up after the Li whisker ceased its growth (corresponding to Supplementary Fig. 18), which stimulated further whisker growth. The movie was recorded at 5 frames per second in BF mode, and played at 24× speed.

Supplementary Video 15

An in situ TEM movie showing the growth of a Li whisker. To explore the relationship between the applied voltage and the growth stress, the potential was ramped up after the Li whisker ceased its growth, which stimulated further whisker growth (corresponding to Supplementary Fig. 19). The movie was recorded at 5 frames per second in BF mode, and played at 18× speed.

Supplementary Video 16

An in situ TEM movie showing the growth of a Li whisker. To explore the relationship between the applied voltage and the growth stress, the potential was ramped up after the Li whisker ceased its growth (corresponding to Supplementary Fig. 2c). The movie was recorded at 5 frames per second in BF mode, and played at 25× speed.

Supplementary Video 17

Assessing the mechanical properties of a Li whisker by in situ compression (corresponding to Supplementary Fig. 22). After its growth, the whisker was pushed up against the AFM cantilever, causing the whisker to deform. The movie was recorded at 5 frames per second in BF mode, and played at 14× speed.

Supplementary Video 18

In situ growth followed by in situ compression of a Li whisker. (corresponding to Supplementary Fig. 23). The whisker was manipulated to contact the AFM tip, causing growth of a secondary whisker over the old one at the bottom, pushing up against the AFM tip under bias. The movie was recorded at 5 frames per second in BF mode, and played at 48× speed.

Supplementary Video 19

Assessing the mechanical properties of a Li whisker by in situ compression (corresponding to Supplementary Fig. 26). After its growth, the whisker was pushed up against the AFM cantilever, causing the whisker to deform. The movie was recorded at 5 frames per second in BF mode, and played at 18× speed.

Rights and permissions

Reprints and Permissions

About this article

Verify currency and authenticity via CrossMark

Cite this article

Zhang, L., Yang, T., Du, C. et al. Lithium whisker growth and stress generation in an in situ atomic force microscope–environmental transmission electron microscope set-up. Nat. Nanotechnol. 15, 94–98 (2020). https://doi.org/10.1038/s41565-019-0604-x

Download citation