Towards the commercialization of rechargeable aqueous zinc ion batteries: The challenge of the zinc electrodeposition at the anode

Integrating molybdenum into zinc vanadate enables Zn3V2MoO8 as a high-capacity Zn-supplied cathode for Zn-metal free aqueous batteries

“…The use of a zinc-metal anode is accompanied by a serious dendrite problem, which has a negative impact on the cycle stability of AZIBs. 41 To solve this problem, referring to the idea of LIBs, we can develop Zn-metal free aqueous batteries by using Zn 3 V 2 MoO 8 as a cathode in conjunction with a non-zinc-metal anode. Herein, brass and 9,10AQ were chosen as the anode and Zn 3 V 2 MoO 8 as a cathode to assemble a Zn-metal free aqueous battery (Fig.…”

Effect of the Current Density on the Electrodeposition Efficiency of Zinc in Aqueous Zinc‐Ion Batteries

“…Indeed when bulk zinc is used, an apparent high efficiency is easily obtained due to the compensation of the charge loss (caused by the parasitic H 2 evolution reaction) by the excess of active metallic zinc in the electrode [38,52] . However, working with a high amount of bulk zinc is not a viable option since: I) a real‐life full Zn‐ion cell will have the requirement of maximizing the specific gravimetric capacity, II) the depth of discharge of realistic Zn‐ion battery devices has to be as high as possible [5,44] …”

“…In fact, high Zn electrodeposition efficiencies that are claimed, are often due to the presence of a great excess zinc in the electrode formulation, and little or no attention is generally given to the parasitic hydrogen evolution reaction occurring at the negative electrode. [44,64] Only further improvements of the Zn electrodeposition efficiency obtained in realistic experimental conditions in terms of depth of discharge, current density and capacity limits close to the ones required by the power grid application will bring aqueous Zn-ion batteries to meet their market requirements.…”

“…[1,7] The percentage of utilization (often referred to as "depth of discharge"-DOD), the current density and the capacity limit of the zinc-based electrode are, indeed, critical parameters that influence the zinc electrodeposition efficiency regardless of the additives or the substrates involved. [5,14,27,43,44] In particular, low current densities induce small overpotentials during the zinc electrodeposition/dissolu-tion, therefore leading to lower hydrogen evolution rates and duller metallic deposits. Moreover, low capacity limits imply a negligible alteration of the electrode surface in terms of morphology and zinc mass deposited during each cycle.…”

Progress and Prospect of Zn Anode Modification in Aqueous Zinc-Ion Batteries: Experimental and Theoretical Aspects

“…In studies of the anode of AZIBs, the electrolytes are generally ZnSO 4 and Zn(OTf) 2 , according to the type of active material of the cathode [ 74 ]. Commonly used cathode materials include manganese-based materials and vanadium-based materials.…”