Improvements in Performance and Cost Reduction of Large-Scale Rechargeable Zinc|Manganese Dioxide Batteries and a Future Roadmap Driven through Real World Applications

Zinc|Manganese Dioxide (Zn|MnO2) are widely available as primary batteries for use in small-scale consumer electronics because of its low cost and high energy density. The last decade has seen a resurgence in research to make this chemistry rechargeable by materials engineering, additives and experimenting with various electrolytes. These important contributions have showed that Zn|MnO2 has all the prerequisites to be a post-lithium solution for grid-scale storage. At Urban Electric Power, we have been commercializing proton-insertion Zn|MnO2 batteries in cylindrical and prismatic form factors between 70 to 140Ah nameplate capacity. These batteries contain improved materials and electrode designs with improved utilizations of the cathode and anode theoretical capacity. Both the cathode and anode can achieve 40 to 60% of their theoretical capacity, which is currently the best in alkaline electrolytes and scaled-up cells. These improvements not only reflect the performance but also the manufacturability of cells on a large scale. In this talk, we will present the methodological approach we pursued to achieve these performance metrics and reduce the cost to <$80/kWh. We also cycled these cells according to various protocols that represent real world applications. For example, we found that the newly improved Zn|MnO2 cells can achieve >6 years of performance for solar microgrid applications, which is better than lead acid batteries, the current battery of choice. We have also manufactured gelled Zn|MnO2 batteries that can be considered as “non-spillable” and thus, “non-hazardous” according to transportation regulations. These non-spillable cells manufacturing process and performance will also be presented in the talk. The talk will also expand on the future generations of Zn|MnO2 that are currently under development at Urban Electric Power like the conversion battery which access the complete 2nd electron capacity of the electrodes and the high voltage (>2.5V) battery. These batteries expand the application space of Zn|MnO2 batteries which make it a viable contender for post lithium-ion batteries.