Efficient Zn-Ion Pouch Cell Assembling Based on Aramid Nanofiber Hydrogel

With the fast advancement of portable and wearable electronics, it is urgent to develop safe, stable and flexible power supply devices. Safe and environmentally friendly aqueous zinc-ion batteries (AZIBs) have a low-cost and are perfect candidates for energy storage device in such applications [1-4]. Giving the general challenges, such as the formation of the dendrites on the Zn anodes and hydrogen evolution and side reactions, extensive and wide research has focused on building stable AZIBs with high performance, but less attention was paid to making Zn ion pouch cells which are flexible and with high capacity In this presentation, we developed an efficient method to assemble Zn-ion pouch cells based on the process of formation of the aramid nanofiber hydrogel. The method involves the dipping precursor solution, solvent exchanging, and in-situ electrodeposition of MnO2. The assembled Zn-ion pouch cells exhibit excellent mechanical performance, flexibility and electrochemical performance, which are ideal for portable and wearable electronics. Based on this method, we successfully assembled 3-layer (cathode/anode/cathode, A/C/A) and 5 layer (A/C/A/C/A) pouch cells with over 100 times higher capacity compared with coin cell. In addition, the pouch cell with aramid nanofiber hydrogel and in-situ electrodeposited MnO2 cathode on carbon nanotube mat demonstrates superior cycling stability [5,6]. More details about our assembling method for flexible and stable pouch cells for AZIBs and experimental measurements related to the cycling and stability characteristics, will be presented at the meeting. [1] Yu, Peng, et al. "Flexible Zn‐ion batteries: recent progresses and challenges." Small 15.7 (2019): 1804760. [2] Li, Yingbo, et al. "Recent advances in flexible zinc‐based rechargeable batteries." Advanced Energy Materials 9.1 (2019): 1802605. [3] Li, Chunyang, et al. "High-rate and high-voltage aqueous rechargeable zinc ammonium hybrid battery from selective cation intercalation cathode." ACS Applied Energy Materials 2.10 (2019): 6984-6989. [4] Yu, Feng, et al. "Aqueous alkaline–acid hybrid electrolyte for zinc-bromine battery with 3V voltage window." Energy Storage Materials 19 (2019): 56-61. [5] Wang, Peng, and Petru Andrei. "High Performance Separator and Hydrogel Based on Aramid Fibers for Zn Ion Batteries." Electrochemical Society Meeting Abstracts 242. No. 4. The Electrochemical Society, Inc., 2022. [6] Xu, Lizhi, et al. "Water‐rich biomimetic composites with abiotic self‐organizing nanofiber network." Advanced Materials 30.1 (2018): 1703343.