Abstract
Rechargeable aqueous aluminum ion batteries (AAIBs) offer a promising avenue for achieving safe, high-energy, and low-cost large-scale energy storage applications. However, the practical development of AAIBs is hindered by competitive reduction reactions in the aqueous solution, which lead to insufficient aluminum (Al) deposition and a severe hydrogen evolution reaction (HRE). In this work, an inorganic/organic hybrid hydrogel with a stable silicon-based network and multiple polar sites is successfully fabricated via an in situ sol-gel polymerization method. The preferential formation of hydrogen bonds between the polar functional groups and water molecules effectively reduces the thermodynamic reactivity of water. Furthermore, X-ray photoelectron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (TOF-SIMS) analyses confirm the formation of a stable, inorganic-rich solid electrolyte interface (SEI) layer, which kinetically suppresses undesirable side reactions. This hydrogel electrolyte exhibits a high ionic conductivity of 2.9 × 10−3 S cm−1 at 25 °C, even under lean-water conditions. As a result, Al|hydrogel|potassium nickel hexacyanoferrate (KNHCF) full cells demonstrate excellent cycling performance, delivering a high initial discharge capacity of 74.9 mAh g−1 at 100 mA g−1 and achieving an outstanding capacity retention of 90.0% after 200 cycles. Additionally, pouch cells exhibit stable open-circuit voltage under various mechanical abuse conditions.
Original language | English |
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Article number | 2500695 |
Journal | Advanced Materials |
Volume | 37 |
Issue number | 15 |
DOIs | |
Publication status | Published - Apr 16 2025 |
Externally published | Yes |
Bibliographical note
Publisher Copyright:© 2025 Wiley-VCH GmbH.
ASJC Scopus Subject Areas
- General Materials Science
- Mechanics of Materials
- Mechanical Engineering
Keywords
- aqueous aluminum ion batteries
- hydrogel electrolyte
- hydrogen evolution rection
- lean-water
- polar functional groups