A Usage Scenario Independent “Air Chargeable” Flexible Zinc Ion Energy Storage Device

Abstract

including natural source of solar, thermal, wind energies, and mechanical energy of human movements, and to compensate energy consumption in energy storage devices. [15][16][17][18][19] For example, the perovskite hybrid solar cells is integrated into graphene based supercapacitor. [20] The solid-state supercapacitors can be charged by perovskite hybrid solar cells and discharged from 0.75 V. The dye-sensitized solar cell also has been assembled with supercapacitor. [21] In addition, various devices were developed via integrating piezoelectric or triboelectric nanogenerators with electro chemical energy storage units. [22][23][24] They can harvest mechanical energy from our living environment such as human movements, [25] vehicle rotations, [26] water waves. [27] However, most current integrated systems are designed by crudely connecting different components through external circuit, such as nanogenerator (Figure 1a) and solar cell ( Figure 1b) based integration systems. The systems are usually rigid and cumbersome with vastly increased volume. [28] More importantly, the two components may be easily de-attached when being exposed to deformations, resulting in poor reliability and durability.Another even more important issue is that, while technologies to harvesting energy from environments are very sophisticated and these integrated systems were well demonstrated, another problem is that these energies possess a density highly dependent on the usage scenario. For example, the solar cells can work well under intense sunlight irradiation but most of the time the users have only indoor lighting available. Similarly, the nanogenerator can only collect ambient mechanical energy at sports mode while most people need to stay quietly to work. Therefore, an energy harvesting technology or system which possesses low dependency to environment and usage scenario is highly expected.Otherwise than other environmental elements, air is full of any corners of our space with almost constant concentration. An "air chargeable" system is expected to be highly reliable.Here, we propose a highly integrated system of "air charging" zinc-ion capacitor/battery. By scavenging energy from pervasive air, a zinc-ion capacitor/battery can be conveniently and easily charged without applying additional power source. The A rationally designed "air chargeable" energy storage device is demonstrated, which can be effectively charged by harvesting pervasive energy from the ambient environment. For an "air chargeable" zinc-ion capacitor system, the system simply consists of a flexible bifunctional "U" shaped electrode (with the functions of energy harvesting and storage), a zinc metal electrode in middle, and two different polyelectrolytes (polyacrylamide and sodium polyacrylate) sandwiched between the zinc metal and "U" shaped electrode. When the zinc-ion capacitor is exhausted, it can be quickly charged to 88% within 10 min by simply opening the sealing tape and allowing the air diffuse in. The capacitor exhausting-air charging processes are repeate...

Hydrogen‐Free and Dendrite‐Free All‐Solid‐State Zn‐Ion Batteries

“…Metallic Zn is regarded as a promising anode material for energy storage system, due to its high theoretical capacity (820 mAh g −1 ), intrinsically safe nature and competitive cost. [ 1–7 ] Unfortunately, a deep‐seated issue in aqueous electrolyte Zn based batteries is that, due to more negative reduction potential of Zn than hydrogen (−0.762 V vs standard hydrogen electrode (SHE)), the Zn is thermodynamically unstable in aqueous system and the parasitic hydrogen evolution reaction (HER) is inevitable (although it can be very slow) in the widely used alkaline or mild‐acid aqueous electrolytes [ 8,9 ] (Figure S1, Supporting Information). While being very slow, during long‐term operation, it will eventually lead to the consumption of Zn and electrolyte, as well as battery swell with the generated hydrogen.…”

Uniform Virus‐Like Co–N–Cs Electrocatalyst Derived from Prussian Blue Analog for Stretchable Fiber‐Shaped Zn–Air Batteries

“…The increasing demand for flexible electronic devices with fascinating features, such as portability, bendability, stretchability, and even wearability, has motivated continuous research on the development of safe, economic, and efficient energy storage and conversion systems . Economical zinc–air batteries (ZABs) with a high theoretical energy density of 1086 Wh kg −1 and low cost have shown promising applications on flexible electronic devices .…”

3D CNTs Networks Enable MnO2 Cathodes with High Capacity and Superior Rate Capability for Flexible Rechargeable Zn–MnO2 Batteries

“…However, the toxic and/or flammable components of LIBs made it impossible to power the future wearable and implantable medical devices that are quite close to the human body . Intrinsic nonflammable aqueous electrolytes greatly revive aqueous batteries for their possible application in flexible configuration . Among various options of aqueous power sources, rechargeable Zn–MnO 2 batteries are emerging as one of the best candidates, owing to the high abundance and safety of both Zn and MnO 2 , as well as stable output voltage platform (≈1.5 V) of the whole device .…”