Towards improving the performance of the negative Zn electrode in Zn-Ion batteries

可充电锌离子电池主要用于非便携式应用，如电网规模的储能，与目前用于这些应用的锂离子电池相比，它具有几个优势，包括由于所采用的水性电解质而具有安全性，同时依赖于廉价、无毒且在加拿大开采/生产的锌。凸极能量公司的锌离子电池包括：(1)负锌电极，直接镀锌和剥离锌；（ii）接近中性的硫酸锌水溶液电解质，配有分离器；（iii）能够可逆插入二价Zn阳离子的正电解MnO2电极。在成功解决了负极电镀/剥离过程中优先（枝晶）Zn生长导致电池短路的问题后，凸极能源公司现在面临着负极Zn的新挑战：寄生腐蚀反应（自腐蚀）会限制循环寿命并产生氢气。总体研究目标是确定电池在负Zn电极循环过程中发生寄生自腐蚀的原因。这将通过三个研究子目标来实现：(i)表征从放大电池中移除的负极上的腐蚀损伤积累，（ii）确定锌金属在接近中性的硫酸锌水溶液中的腐蚀机制，以及（iii）确定层压负极组件固有的锌-黄铜偶对的电偶腐蚀敏感性。该项目将为识别和评估基于科学的新型腐蚀控制策略提供新知识。该项目将为为期两年的任务补助金项目培训一名PDF。

Rechargeable Zn-ion batteries are targeted for non-portable applications, such as grid-scale energy storage, and provide several advantages over the Li-ion batteries currently used for these applications, including safety due to the aqueous electrolytes employed, while relying on Zn that is inexpensive, non-toxic and mined/produced within Canada. Salient Energy's Zn-ion batteries consist of: (i) negative Zn electrode where direct plating and stripping of Zn occurs; (ii) near-neutral aqueous Zn sulphate electrolyte, complete with a separator; and (iii) positive electrolytic MnO2 electrode capable of reversibly intercalating divalent Zn cations. Having successfully addressed problematic preferential (dendritic) Zn growth during plating/stripping at the negative electrode, which serves to short-circuit the battery, Salient Energy now faces a new challenge with the negative Zn electrode: parasitic corrosion reactions (self-corrosion) that limit cycle life and produce hydrogen gas. The overarching research objective is to determine the cause of the parasitic self-corrosion that occurs during cycling of the battery at the negative Zn electrode. This will be achieved through the three research sub-objectives: (i) characterize the corrosion damage accumulation on negative electrodes removed from scaled-up batteries, (ii) determine the corrosion mechanism of Zn metal in near-neutral aqueous Zn sulphate electrolytes, and (iii) determine the galvanic corrosion susceptibility of the Zn-brass couple that is intrinsic to the laminated negative electrode assembly. The project will create new knowledge that is required for novel science-based corrosion control strategies to be identified and evaluated. The project will train one PDF for the two year Missions Grant project.