Interface design for all-solid-state lithium batteries

• Published in: Nature (London) 2023-11, Vol.623 (7988), p.739-744
• Main Authors: Wan, Hongli, Wang, Zeyi, Zhang, Weiran, He, Xinzi, Wang, Chunsheng
• Format: Article
• Language: English
• Subjects: 639/301/299/891; 639/4077/4079/891; Alloys; Anodes; Cathodes; Dendrites; Design; Electric fields; Electrochemistry; Electrolytes; Energy; Humanities and Social Sciences; Interfaces; Interlayers; Intermetallic compounds; Lithium; Lithium batteries; multidisciplinary; Plating; Science; Science (multidisciplinary); Solid electrolytes; Solid solutions; Solid state
• ISSN: 0028-0836; 1476-4687
• DOI: 10.1038/s41586-023-06653-w

The operation of high-energy all-solid-state lithium-metal batteries at low stack pressure is challenging owing to the Li dendrite growth at the Li anodes and the high interfacial resistance at the cathodes 1 – 4 . Here we design a Mg 16 Bi 84 interlayer at the Li/Li 6 PS 5 Cl interface to suppress the Li dendrite growth, and a F-rich interlayer on LiNi 0.8 Mn 0.1 Co 0.1 O 2 (NMC811) cathodes to reduce the interfacial resistance. During Li plating–stripping cycles, Mg migrates from the Mg 16 Bi 84 interlayer to the Li anode converting Mg 16 Bi 84 into a multifunctional LiMgS x –Li 3 Bi–LiMg structure with the layers functioning as a solid electrolyte interphase, a porous Li 3 Bi sublayer and a solid binder (welding porous Li 3 Bi onto the Li anode), respectively. The Li 3 Bi sublayer with its high ionic/electronic conductivity ratio allows Li to deposit only on the Li anode surface and grow into the porous Li 3 Bi sublayer, which ameliorates pressure (stress) changes. The NMC811 with the F-rich interlayer converts into F-doped NMC811 cathodes owing to the electrochemical migration of the F anion into the NMC811 at a high potential of 4.3 V stabilizing the cathodes. The anode and cathode interlayer designs enable the NMC811/Li 6 PS 5 Cl/Li cell to achieve a capacity of 7.2 mAh cm −2 at 2.55 mA cm −2 , and the LiNiO 2 /Li 6 PS 5 Cl/Li cell to achieve a capacity of 11.1 mAh cm −2 with a cell-level energy density of 310 Wh kg −1 at a low stack pressure of 2.5 MPa. The Mg 16 Bi 84 anode interlayer and F-rich cathode interlayer provide a general solution for all-solid-state lithium-metal batteries to achieve high energy and fast charging capability at low stack pressure. The inclusion of a Mg–Bi-based interlayer between the lithium metal and solid electrolyte and a F-rich interlayer on the cathode improves the stability and performance of solid-state lithium-metal batteries.