An Investigation into the Charge Storage Mechanism and Cycling Performance of Mn2O3 as the Cathode Material for Zinc‐Ion Batteries. Issue 9 (14th July 2022)

• Record Type: Journal Article
• Authors: Hou, Qingping; Ivey, Douglas G.
• Is Part Of: Batteries & supercaps. Volume 5:Issue 9(2022)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2022-07-14
• Subjects: aqueous electrolyte -- bixbyite Mn2O3 -- cathode material -- energy storage mechanism -- zinc-ion batteries; Electrochemistry -- Periodicals; Electrodes -- Periodicals; Electric batteries -- Periodicals; 621.31242
• DOI: 10.1002/batt.202200190
• Languages: English
• ISSNs: 2566-6223

Abstract

Abstract: In this work, highly crystalline, nanosize Mn2 O3 powder is synthesized via a precipitation and calcination method for utilization as the cathode in aqueous zinc‐ion batteries (aZIBs). The resultant electrodes are characterized using electrochemical and microstructural methods to determine the mechanisms associated with charge and discharge. In addition, a few quantitative testing methods are used to investigate cycling performance stability. A specific capacity of 211 mAh g −1 is retained after 200 cycles at a current density of 500 mA g −1 with 93 % capacity retention. Also, 73 % capacity retention can be reached after 1100 cycles at 2000 mA g −1 . The energy storage mechanism associated with Mn2 O3 is for the first time proposed to be a chemical conversion reaction type with two steps involving the formation/decomposition of ZnMn2 O4 (hetaerolite) and zinc sulphate hydroxide (ZHS). Also, capacity fading is directly linked to the incomplete reversibility of the chemical conversion reaction mechanism. Abstract : Aqueous Znic‐ion battery (aZIB) cathode : The charge storage mechanism for Mn2 O3 as the cathode material in aZIBs is still not well understood. A new mechanism has been proposed and involves two chemical conversion reactions resulting in the formation of hetaerolite (ZnMn2 O4 ) during the 1 st discharge plateau followed by zinc hydrate sulfate (ZHS) formation during the 2 nd discharge plateau.