Solid‐State Rechargeable Zinc–Air Battery with Long Shelf Life Based on Nanoengineered Polymer Electrolyte

Abstract

Zinc-air batteries (ZABs) are vulnerable to the ambient environment (e.g., humidity and CO ), and have serious selfdischarge issues, resulting in a short shelf life. To overcome these challenges, a near-neutral quaternary ammonium (QA) functionalized polyvinyl alcohol electrolyte membrane (different from conventional alkali-type membranes) has been developed. QA functionalization leads to the formation of interconnected nanochannels by creating hydrophilic/-phobic separations at the nanoscale. These nanochannels selectively transport OH ions with a reduced migration barrier, while inhibiting [Zn(NH ) ] crossover. Owing to the superior water retention ability and enhanced chemical stability of the membrane, the solid-state zinc-air battery (SZAB) displays outstanding flexibility, a promising cycle lifetime, and a large volumetric energy density. More importantly, the self-discharge rate of SZAB is depressed to less than 7 % per month, and the fully dehydrated SZAB could recover its rechargeability upon replenishment of the solution of NH Cl.

A Rechargeable Zn–Air Battery with High Energy Efficiency and Long Life Enabled by a Highly Water‐Retentive Gel Electrolyte with Reaction Modifier

“…Figure 4e plots the working life and charge voltage values of sandwich‐type KI–PVAA–GO‐based ZABs together with the counterpart values of the recently reported flexible ZABs. [ 3,6e,9a,10,13a,14a,25a,40 ] Remarkably, the data points of this work are beyond the typical data zone of the current flexible ZABs in terms of both longer life and lower charging voltage, demonstrating the great improvement of flexible ZABs by applying KI–PVAA–GO GPE. Inspired by the urgent demand for knittable batteries to power wearable electronic devices, we also fabricated 1D cable‐type ZABs with KI–PVAA–GO GPE.…”

“…[ 8 ] Some attempts in seeking other better GPE systems have been made, providing strategies that inspire the modification of PVA‐based GPEs. For instance, highly hydrophilic and/or alkaline tolerant additives, such as quaternary ammonium (QA), [ 9 ] guar hydroxypropyltrimonium chloride (GG), [ 10 ] cellulose, [ 11 ] and chitosan particles, [ 12 ] could greatly improve the ionic conductivity and/or the stability of GPEs. Besides, other polymers and compounds such as poly(acrylic acid) (PAA), [ 13 ] sodium polyacrylate (PANa), [ 14 ] and polyacrylamide (PAM), [ 13a,15 ] have shown to exhibit excellent water retention capability, showing great promise in optimizing PVA‐based GPEs.…”

“…First, the stronger water uptake capabilities of PVAA and PVAA–GO contribute to an increased amount of hydroxide ions within the polymer matrices, providing more sufficient charge carriers for facile transport. [ 9b,33 ] Second, the lower degree of crystallinity for PVAA and PVAA–GO leads to a reduced energy barrier for ionic diffusion, thereby facilitating hydroxide ion transport through the polymer. [ 24a,34 ] Moreover, the distribution of GO throughout the polymer matrix can provide an abundant charge transfer channel to facilitate ion transport.…”

Pursuit of reversible Zn electrochemistry: a time-honored challenge towards low-cost and green energy storage

“…10). Lin et al 117 reported that PVA functionalized with quaternary ammonium was used as an electrolyte, which depressed the self-discharge rate of AZB to less than 7% per month due to the inhibition of [Zn(NH 3 ) 6 ] 2+ crossover. To compensate for the limited ion conductivity of nonporous single-ion conductors, a sandwich-type electrolyte configuration was designed.…”

A Review of the Use of GPEs in Zinc-Based Batteries. A Step Closer to Wearable Electronic Gadgets and Smart Textiles

“…The use of Co 3 O 4 as catalyst in air electrodes, some other catalysts are also explored, in flexible batteries PVA-based has been fruitful. The most common feature is the use of carbon cloths as substrate, not exclusive, where the catalyst is applied using diverse techniques and with different nanostructured morphologies [224][225][226]. The following works describe flexibles zinc-air batteries, with different geometries, where huge effort have been put in developing air electrodes with enhanced capabilities.…”