An integrated, flexible aqueous Zn-ion battery with high energy and power densities

Energy storage devices are usually stacked from two electrodes and a sandwiched separator. The possible de lamination of the stacked structure could deteriorate the electrochemical performance under deformed states. Here the cathode (polyaniline) and anode (metal Zn) are separately electrodeposited on a filter paper coated with current collectors to produce an integrated aqueous Zn-ion battery. High energy and power densities of 175.1 mWh/g@0.43 W/g and 12.1 W/g@90.1 mWh/g, together with excellent cyclic stability, are achieved for the integrated aqueous Zn-ion battery. The electrochemical performance is advantageous over that of Li-ion paper batteries with organic electrolytes and asymmetric supercapacitors with aqueous electrolytes. Impressively, the integrated aqueous Zn-ion battery works well under bending, folding and twisting, respectively, with little loss in the electrochemical performance.