Construction of Alkaline Gel Polymer Electrolytes with a Double Cross-Linked Network for Flexible Zinc–Air Batteries

Abstract

Flexible zinc–air batteries have broad potential as the next generation of energy storage component in wearable electronic devices. However, the mechanical performance and ionic conductivity of electrolytes are urgent issues that hinder the commercial application of flexible batteries. Herein, the alkaline gel polymer electrolyte (AGPE) with a double-network structure is developed, which consists of a covalently cross-linked polyacrylamide (PAM) by in situ polymerization and a physically cross-linked poly(vinyl alcohol) (PVA) by the freeze–thaw method. The freestanding PVA/N-PAM/KOH gel electrolyte demonstrates high ionic conductivity (309.9 mS cm–1) and excellent mechanical toughness (0.69 MJ m–3), benefiting from the synergistic effect of the double cross-linked system and hydrogen bonds. Meanwhile, the assembled ″sandwich″-type zinc–air battery presents excellent power density (40.43 mW cm–2), long-term cycle life (113 cycles), super-high-energy efficiency (70.2%), and stable discharge plateau. Impressively, the PVA/N-PAM/KOH-based batteries attached to the human body surface are reliably capable of powering light-emitting diodes.

In Situ Construction of Zwitterionic Polymer Electrolytes with Synergistic Cation–Anion Regulation Functions for Lithium Metal Batteries

“…It means that temperatures break intra-and inter-molecular hydrogen bonds. [19] As we know, the movement of polymer chains mainly facilitates Li + transport in the polymer electrolyte. The low glass transition temperature (T g ) and crystallinity of the polymers facilitate Li + transport.…”

Recent progress in structural modification of polymer gel electrolytes for use in solid-state zinc-ion batteries

“…The main components of common hydrogel electrolytes are PVA, 67,85,86 polyacrylamide (PAM), 87–89 PEO, 90–92 polyvinyl chloride (PVC), 93,94 and xanthan gum (XG). 95–97 The above materials show excellent flexibility and good ionic conductivity as gel electrolytes.…”

Design enhancement in hydroxide ion conductivity of viologen–bakelite organic frameworks for a flexible rechargeable zinc–air battery

“…They generally do not swell under aqueous conditions, hence as solid electrolytes, they will adhere to the electrode as its volume increases or reduces during charging and discharging, respectively. 51,52 Thus, in this study, a thin hydroxide ion-conducting solid-state separator coupled with an electrolyte has been devised for use in ZABs by a combination of cationic polymer with PVA through simple solution processing.…”