Energies, Vol. 19, Pages 615: High Volumetric Capacity Lithium Primary Battery via CuO and FeS2 All-Active-Material Cathodes
Energies doi: 10.3390/en19030615
Authors:
Chen Cai
Byeongcheol Min
Gary M. Koenig
Low-voltage primary batteries broadly power small electronics used in health, biomedical, and wearable applications. These devices are generally more sensitive to volumetric capacity than gravimetric capacity. The current state-of-the-art button battery is Zn-Ag2O, where contributors that limit volumetric capacity include the incorporation of inactive materials in the electrode microstructure such as gelling agents, binders, and conductive additives. Herein, cathode materials of CuO and FeS2 will be described for small form factor coin/button cells. When paired with Li metal anodes, the operating voltage is similar to Zn-Ag2O. The key innovation is that they will be processed into all-active-material (AAM) electrode architectures, where the electrodes will comprise only electroactive materials and pores that are filled with electrolyte during cell fabrication. The AAM architecture significantly enhanced electroactive material volume utilization, and thus volumetric capacity. FeS2 and CuO were processed into AAM electrodes under various processing conditions, and Li-FeS2 and Li-CuO primary batteries were fabricated and evaluated. At the cell level, volumetric capacity of 1300 mAh cm−3 was achieved, and in a button cell form factor 395/927, nearly 100 mAh was delivered, which compares favorably with commercially available options, which typically range from 27 to 55 mAh.