Recent Progress in Aqueous Ammonium-Ion Batteries

Abstract

Batteries using a water-based electrolyte have the potential to be safer, more durable, less prone to thermal runaways, and less costly than current lithium batteries using an organic solvent. Among the possible aqueous battery options, ammonium-ion batteries (AIBs) are very appealing because the base materials are light, safe, inexpensive, and widely available. This review gives a concise and useful survey of recent progress on emerging AIBs, starting with a brief overview of AIBs, followed by cathode materials, anode materials, electrolytes, and various devices based on ammonium-ion storage. Aside from summarizing the most updated electrodes/electrolytes in AIBs, this review highlights fundamental mechanistic studies in AIBs and state-of-the art applications of ammonium-ion storage. The present work reviews various theoretical efforts and the spectrum studies that have been used to explore ionic transport kinetics, electrolyte structure, solvation behavior of ammonium ions, and the intercalation mechanism in the host structure. Furthermore, diverse applications of ammonium-ion storage apart from aqueous AIBs are discussed, including flexible AIBs, AIBs that can operate across a wide temperature range, ammonium-ion supercapacitors, and battery–supercapacitor hybrid devices. Finally, the review is concluded with perspectives of AIBs, challenges remaining in the field, and possible research directions to address these challenges to boost the performance of AIBs for real-world practical applications.

A metal-free all-organic ammonium-ion battery with low-temperature applications

“…1e displays the N 1s XPS spectrum of PPy that shows nitrogen groups at 400.03, 401.77 and 397.75 eV corresponding to –NH– with an atomic weight percentage of 61.27%, –NH + – with 35.33%, and –C–N with 3.39%, respectively. 47 The presence of FeCl 3 during synthesis would result in polarons and bipolarons that have a delocalized spin which is responsible for the conductivity of PPY. Additionally, Fig.…”

“…Additionally, it has the smallest hydration radius of 3.31 Å despite a large ionic radius of 1.48 Å, resulting in faster kinetics in the electrolyte. 13 Finally, the NH 4 + ion entails flexible hydrogen bonds with host materials, which are different and weaker than the ionic bonds between metallic charge carriers and electrodes. Nevertheless, the large ionic radius of the ammonium ion requires host materials with larger open structures to accommodate it during charging/discharging, which limits the electrode material choices.…”

Screening of electrode materials for ammonium ion batteries by high throughput calculation

“…are relatively expensive in terms of abundance in Earth's crust and mining cost. Emerging non-metallic batteries (proton, 4 NH 4 + , 5 Cl − , 6 etc. ) have developed rapidly in recent years.…”

“…The progress of ammonium-ion batteries (AIBs) 5,9,11–15 is still in its infancy. Ji's team systematically studied the insertion of NH 4 + into layered V 2 O 5 .…”

“…7,8 Compared with acidic electrolytes, electrolytes containing NH 4 + show weak acidity and are less corrosive, will not lead to the dissolution of electrode materials and have higher HER (hydrogen evolution reaction) overpotential than electrolytes containing H + . 9,10 The progress of ammonium-ion batteries (AIBs) 5,9,[11][12][13][14][15] is still in its infancy. Ji's team systematically studied the insertion of NH 4…”