(Invited) How Does One Enable High Energy Li Metal Batteries a Case Study with Lipon

The next generation of high energy batteries using Li metal as an anode and utilizing a solid electrolyte requires good interfacial stability, reasonable ionic conductivity, and most importantly the ability to eliminate dendrites.i While most solid-state electrolytes suffer from both interfacial instability and Li penetration resulting in cell shorting,ii,iii The solid electrolyte Lipon has a remarkable ability to suppress dendrites, and enable solid state batteries that can cycle for more than 1000 cycles and support current densities as high as 10 mA/cm2.iii,iv Recent efforts have started to illuminate the origin of Lipon’s ability to enable high-energy solid-state Li metal batteries. This presentation will highlight the unique structure of Lipon and Lipon like materials, the interfacial structure of Lipon with Li metal, and the mechanics that enable high quality performance in Lipon based solid-state batteries.v,vi,vii Finally, the presentation will connect these findings from Lipon to outline key underlying principles that answer the question, how do we enable high energy Li metal batteries? Acknowledgements: Work for this presentation was funded by ARPA-E under contract #DE-AR0000775, and the US Department of Energy Office of Energy Efficiency and Renewable Energy for the Vehicle Technologies Office’s US-German Cooperation on Energy Storage: Interfaces and Interphases In Rechargeable Li-metal based Batteries Program and the Battery Materials Research Program under program managers Tien Duong and Simon Thompson. P. Albertus et al., “Challenges for and pathways toward Li-metal-based all-solid-state batteries”, ACS Energy Letters, 6, 4, 1399-1404, Mar. 2021. Fudong Han, Andrew S Westover, Jie Yue, Xiulin Fan, Fei Wang, Miaofang Chi, Donovan N Leonard, Nancy J Dudney, Howard Wang, Chunsheng Wang, “High electronic conductivity as the origin of lithium dendrite formation within solid electrolytes”, Nature Energy, 1, Jan. 2019. Andrew S Westover, Nancy J Dudney, Robert L Sacci, Sergiy Kalnaus, “Deposition and Confinement of Li Metal along an Artificial Lipon–Lipon Interface”, ACS Energy Letters, 4, 651-655, Feb. 2019. Juchuan Li, Cheng Ma, Miaofang Chi, Chengdu Liang, and Nancy J. Dudney. "Solid electrolyte: the key for high‐voltage lithium batteries." Advanced Energy Materials5, 4, 1401408, 2015. Andrew S Westover* Valentina Lacivita,* , Andrew Kercher, Nathan D Phillip, Guang Yang, Gabriel Veith, Gerbrand Ceder, Nancy J Dudney, “Resolving the amorphous structure of lithium phosphorus oxynitride (Lipon)”, Journal of the American Chemical Society 140 (35), 11029-11038, July 2018. Andrew S Westover, Robert L Sacci, Nancy Dudney, “Electroanalytical measurement of interphase formation at a Li metal–solid electrolyte interface”, ACS Energy Letters, 5, 12, 3860-3867, Nov. 2020. Sergiy Kalnaus, Andrew S Westover, Mordechai Kornbluth, Erik Herbert, Nancy J Dudney, “Resistance to fracture in the glassy solid electrolyte Lipon”, Journal of Materials Research, 36, 4, 787-796, Feb. 2021.