Redox-homogeneous, gel electrolyte-embedded high-mass-loading cathodes for high-energy lithium metal batteries

• Published in: Nature communications Vol. 13; no. 1; pp. 2541 - 11
• Main Authors: Kim, Jung-Hui, Kim, Ju-Myung, Cho, Seok-Kyu, Kim, Nag-Young, Lee, Sang-Young
• Format: Journal Article
• Language: English
• Published: London Nature Publishing Group UK 09.05.2022; Nature Publishing Group; Nature Portfolio
• Subjects: 147/135; 147/136; 147/143; 147/28; 639/166; 639/301; 639/301/299/161; 639/4077/4079/891; 639/638/675; Aging; Cathodes; Drying; Electrodes; Electrolytes; Energy; ENERGY STORAGE; Flux density; Homogeneity; Humanities and Social Sciences; Lithium; Lithium batteries; Lithium ions; Metals; multidisciplinary; Rechargeable batteries; Redox reactions; Science; Science & Technology - Other Topics; Science (multidisciplinary); Solvents; Ultraviolet radiation
• ISSN: 2041-1723; 2041-1723
• DOI: 10.1038/s41467-022-30112-1

Lithium metal batteries have higher theoretical energy than their Li-ion counterparts, where graphite is used at the anode. However, one of the main stumbling blocks in developing practical Li metal batteries is the lack of cathodes with high-mass-loading capable of delivering highly reversible redox reactions. To overcome this issue, here we report an electrode structure that incorporates a UV-cured non-aqueous gel electrolyte and a cathode where the LiNi 0.8 Co 0.1 Mn 0.1 O 2 active material is contained in an electron-conductive matrix produced via simultaneous electrospinning and electrospraying. This peculiar structure prevents the solvent-drying-triggered non-uniform distribution of electrode components and shortens the time for cell aging while improving the overall redox homogeneity. Moreover, the electron-conductive matrix eliminates the use of the metal current collector. When a cathode with a mass loading of 60 mg cm −2 is coupled with a 100 µm thick Li metal electrode using additional non-aqueous fluorinated electrolyte solution in lab-scale pouch cell configuration, a specific energy and energy density of 321 Wh kg −1 and 772 Wh L −1 (based on the total mass of the cell), respectively, can be delivered in the initial cycle at 0.1 C (i.e., 1.2 mA cm −2 ) and 25 °C. The development of high energy lithium metal batteries is affected by the mass loading of the cathode. Here, the authors report a lithium metal pouch cell with a cathode capacity of 12 mAh cm-2. The positive electrode is prepared by applying UV-curable gel electrolyte as a processing solvent.