A self-healing aqueous ammonium-ion micro batteries based on PVA-NH <sub>4</sub>Cl hydrogel electrolyte and MXene-integrated perylene anode
Ke Niu, Junjie Shi, Long Zhang, Yue Yang, Mengjie Wang, Qixiang Zhang, Yanan Ma, Shuyi Mo, Shaofei Li, Wenbiao Li, Wen Li, Yixin Hou, Fei Long, Yihua Gao
Abstract
The successful study of self-healing aqueous micro batteries (AMBs) which inherit the advantages of aqueous batteries and have the ability to automatically repair damage is of great significance for the development of smart wearable and portable electronic devices. However, the rate performance and the related power density of developed self-healing AMBs using metal ions as charge carriers is limited, due to the strong interaction between metal ions and electrode materials. Therefore, there is great potential for developing self-healing NH<sub>4</sub><sup>+</sup> AMBs, because of the outstanding advantages of NH<sub>4</sub><sup>+</sup> such as extremely abundant reserves, smaller hydrated ion radius and little molar mass. However, the development of selfhealing NH<sub>4</sub><sup>+</sup> AMBs is still an extremely challenge due to the difficulty in developing self-healing hydrogels and instability of anode materials. Even though, the firstly self-healing NH<sub>4</sub><sup>+</sup> AMBs based on tailoring hydrogel electrolyte and MXeneintegrated perylene anode were successfully assembled. As expected, self-healing NH<sub>4</sub><sup>+</sup> AMBs exhibit excellent energy density (82.48 μWh·cm<sup>−2</sup>) and power density (3.09 mW·cm<sup>−2</sup>), cycle life (81.67% after 3000 GCD cycles), flexibility (95.68% under 180°) and self-healing ability (94.16% after the 10<sup>th</sup> self-healing cycles).