Preparation Of Self-healable Hydrogel And Its Application In Aqueous Energy Storage Devices

Energy storage devices can be easily damaged during use,conventional energy storage devices may cause fire or even explode if they are damaged,so this is harmful to the user.To avoid this possibility,this paper designs the e nergy storage devices with self-healable function.In this work,the self-healable and hi-1 ionic conductive hydrogel electrolyte was prepared via crosslinking dopamine-modified sodium alginate with borax.The self-healable positive and negative hydrogel electrode was synthesized throu-1 binding Li Mn2O4?LiV3O8 and activated carbon in borax-crosslinked quaternized polyvinyl alcohol network.The lithium ion hybrid capacitor and lithium ion battery which could self-heal multiple times,was constructed by stacking the electrode-electrolyte-electrode layers together like a sandwich.The results showed that,the capacity of llithium ion battery was calculated by the active material Li Mn2O4,in the first few circles,the specific capcity of lithium ion battery decreased obviously,but then it stabilised.Under the current density of 1 A�g-1,the specific capacity of the lithium ion battery could reach about 30 m Ah�g-1,respectively.It kept a capacity retention of 79.92% after 100 cycles under 1A�g-1.The flexible battery could be healed by simple contact after cutted.After 7 cut off/healing processes,the battery remained a specific capacity of 34.69 m Ah�g-1 under the current density of 0.5 A�g-1.Due to its outstanding self-healability,the battery could be tailored and rejoin together,after the battery was tailored,the specific capacity was reduced from 35 m Ah�g-1 to 20 m Ah�g-1.Besides,the battery could also be bended from 0� to180� angles,and its electrochemical properties were still maintained by the bended to the large Angle.The results showed that,the capacity of lithium ion hybrid capacitor was calculated by the active material Li Mn2O4,under the current density of 1 A�g-1 and 5 A�g-1,the specific capacity of the hybrid capacitor could reach 60 m Ah�g-1 and 26 m Ah�g-1,respectively.It kept a capacity retention of 96.5% after 200 cycles under 1 A�g-1,presenting a good cycling performance.After 7 cut off/healing processes,the capacitor remained a specific capacity of 55.76 m Ah�g-1,which maintained 93% of the original value.Due to its outstanding self-healability,the capacitor could be tailored and rejoin together like a jigsaw puzzle,after the capacitor was tailored,the specific capacity was reduced from 65 m Ah�g-1 to 57 m Ah�g-1.Besides,the capacitor could also be bended from 0� to180� angles,and the electrochemical properties of the capacitor were not affected.