High‐Performance Packaged 3D Lithium‐Ion Microbatteries Fabricated Using Imprint Lithography

Fabrication of high‐energy‐density and high‐power‐density packaged long‐cycle‐life rechargeable microbatteries remains a considerable challenge. Here, high‐performance microbatteries with high active volume fraction, thick, 3D‐structured electrodes (V2O5 cathode and Li metal anode) are realized through a combination of imprint lithography, self‐assembly, and electrodeposition. To assist the critical challenge of hermetic packaging, the microbattery is infilled with a gel electrolyte. The packaged cell exhibits high areal energy and power densities of 1.24 J cm−2 and 75.5 mW cm−2, respectively, and can be cycled 550 times in argon or 200 times in air with 75% capacity retention of the initial discharge capacity. An unpackaged cell, using a liquid electrolyte, provides a power density of 218 mW cm−2. As far as it is known, the microbatteries have the highest peak power density among all reported microbatteries. High‐performance microbatteries with high active volume fraction, thick, 3D‐structured electrodes (V2O5 cathode and Li metal anode) are realized through a combination of imprint lithography, self‐assembly, and electrodeposition. The microbattery is infilled with a gel electrolyte to facilitate hermetic packaging. The packaged cell exhibits high areal energy and power densities of 1.24 J cm−2 and 75.5 mW cm−2, respectively.