Daniel Höche

Mg Alloys: Challenges and Achievements in Controlling Performance, and Future Application Perspectives

In recent years, Mg alloys have made inroads into applications for transport industries. The favorable property profile of Mg promotes increased usage. Despite magnesium alloys being used for years, there is still a lack of knowledge about the potential of Mg alloys. New or optimized alloys and processes are creating new ideas for substituting traditional materials. High-pressure die-casting (HPDC) is the predominant technology, while other casting and wrought processes are of secondary importance. Developments in the last decade have led to an improvement of the property profile and effectiveness of magnesium wrought alloys. Additive manufacturing has opened new opportunities for tailoring of the property profile and functionality. In addition, Mg as material for battery anodes adds a new field of application in the energy sector. This presentation will provide an overview of the status of modern process and alloy development, and discuss the challenges to extending the use of magnesium alloys in various applications.

Performance boost for primary magnesium cells using iron complexing agents as electrolyte additives

Aqueous Mg battery technology holds significant appeal, owing to the availability of raw materials, high power densities and the possibility of fast mechanical recharge. However, Mg batteries have so far been prone to decreased capacity due to self-corrosion of the anodes from the electrochemical redeposition of impurities, such as Fe, which results in parasitic cathodically active sites on the discharging anode. This work demonstrates that by adding Fe3+-complexing agents like Tiron or salicylate to the aqueous electrolyte of an Mg battery, it was possible to prevent the redeposition of Fe impurities and subsequent self-corrosion of the anode surface, thereby boosting battery performance. To prevent detrimental fouling of anode surface by Mg(OH)2, employed Fe3+-complexing agents must also form soluble complexes with Mg2+ of moderate stability. The interplay of these requirements predetermines the improvement of operating voltage and utilization efficiency.