Large-area surface-patterned Li metal anodes fabricated using large, flexible patterning stamps for Li metal secondary batteries

Abstract

The use of surface-patterned lithium (Li) metal has been proposed as a promising strategy for inhibiting the formation of Li dendrites during repeated Li plating/stripping processes. Nevertheless, the conventional Li metal patterning process is complex, expensive, incompatible with mass production, and incapable of producing finely controlled patterns on the Li metal surface. A large, flexible patterning stamp capable of large-area patterns is developed using a silicon (Si) wafer-based chemical etching process, and its effect on the electrochemical performance of a Li metal anode is investigated. The newly developed stamps have 5,000% larger patterning area compared to the conventional stainless-steel stamps. Furthermore, when compared to conventional surface-patterned Li metal fabricated with conventional stainless-steel stamps (SP-LM), the surface-patterned Li metal fabricated with large and flexible patterning stamps (LAP-LM) demonstrates improved electrochemical performance and stable morphological properties. As a result, the LAP-LM is able to retain up to 85.2% of its initial discharge capacity (85.9 mAh g −1 ) after 200 cycles at 3C (3.96 mA cm −2 ), while the SP-LM shows a severe capacity decay after 150 cycles (94.0 mAh g −1 and 13.0 mAh g −1 at the 150th cycle and 200th cycle, respectively). • A large, flexible patterning stamp capable of large-area patterns was developed. • The newly developed stamps achieved 5,000% larger patterning area for Li metal. • The new large-area stamp produced stable morphological properties for Li metal. • The new large-area stamp showed significantly improved electrochemical properties.