Liquid metal welding enabling high loading binder/carbon-free layered oxide cathode toward high-performance liquid and solid-state battery

• Published in: Rare metals 2023-05, Vol.42 (5), p.1583-1593
• Main Authors: Han, Xiang, Gu, Lan-Hui, Xu, Min, Chen, Min-Feng, Chen, Ji-Zhang
• Format: Article
• Language: English
• Subjects: Biomaterials; Carbon; Cathodes; Chemistry and Materials Science; Cobalt oxides; Electrolytic cells; Electron transport; Energy; Heat treatment; Indium oxides; Indium tin oxides; Interfacial properties; Liquid metals; Lithium compounds; Lithium-ion batteries; Materials Engineering; Materials Science; Melting points; Metallic Materials; Nanoscale Science and Technology; Original Article; Physical Chemistry; Rechargeable batteries; Robustness; Solid state; Tin dioxide; Welding
• ISSN: 1001-0521; 1867-7185
• DOI: 10.1007/s12598-022-02229-1

High loading cathode with high active material proportion is a practical demand but far below the desirable value to achieve high energy density lithium-ion batteries (LIBs). Normally, the Li + /electron transport between active materials and electrolyte/carbon, however, it is poor and areal resistance is extremely high for a high loading/thick cathode. In this manuscript, taking high-voltage lithium cobalt oxide LiCoO 2 (LCO) as an example, we design a facile liquid metal welding method enabled by a low melting-point indium-tin oxide In 2 O 3 /SnO 2 (ITO) during a thermal treatment process, the strongly adhesion active particles show robust mechanical property for the free-standing LCO cathode with a pellet architecture. We also demonstrate that the O 2 atmosphere plays a critical role on the interfacial property, that is preventing the layered structure to rock-salt Co 3 O 4 as well as further enhancing the interfacial mechanical integration. As expected, the LCO-ITO free-standing cathode not only shows robust mechanical property with densely packed configuration but also provides a fast Li + /electron pathway at the interface. Consequently, the LCO-ITO composite cathode exhibits excellent electrochemical cycling performance in both liquid and solid-state cells. For example, even at a high active material mass of 56 mg·cm −2 , the LCO cathode still delivers a specific capacity of 151 mAh·g −1 and maintains 132.5 mAh·g −1 (corresponding to 7.4 mAh·cm −2 ) after 80 cycles. The LCO-ITO-O 2 cathode is also applicable to a solid-state cell, which exhibits a high capacity of 100.4 mAh·g −1 after 200 cycles of long-term cycling. The excellent electrochemical of the LCO-ITO-O 2 reveals the successful engineering mechanical architecture and interfacial carriers transport, which may be expected as an alternative approach to achieve high energy density LIBs. Graphical abstract