Recently, rechargeable aluminum batteries have received much attention due to their low cost, easy operation, and high safety. As the research into rechargeable aluminum batteries with a room-temperature ionic liquid electrolyte is relatively new, research efforts have focused on finding suitable electrode materials. An understanding of the environmental aspects of electrode materials is essential to make informed and conscious decisions in aluminum battery development. The purpose of this study was to evaluate and compare the relative environmental performance of electrode material candidates for rechargeable aluminum batteries with an AlCl₃/EMIMCl (1-ethyl-3-methylimidazolium chloride) room-temperature ionic liquid electrolyte. To this end, we used a lifecycle environmental screening framework to evaluate 12 candidate electrode materials. We found that all of the studied materials are associated with one or more drawbacks and therefore do not represent a “silver bullet” for the aluminum battery. Even so, some materials appeared more promising than others did. We also found that aluminum battery technology is likely to face some of the same environmental challenges as Li-ion technology but also offers an opportunity to avoid others. The insights provided here can aid aluminum battery development in an environmentally sustainable direction.

The foreseen high penetration of fluctuant renewable energy sources, such as wind and solar, will cause an increased need for batteries to store the energy produced and not instantaneously consumed. Due to the high production cost and significant environmental impacts associated with the production of lithium-ion nickel-manganese-cobalt (Li-ion NMC) batteries, several chemistries are proposed as a potential substitute. This study aims to identify and compare the lifecycle environmental impacts springing from a novel Al-ion battery, with the current state-of-the-art chemistry, i.e., Li-ion NMC. The global warming potential (GWP) indicator was selected to express the results due to its relevance to society, policy and to facilitate the comparison of our results with other research. The cradle-to-grave process-based assessment uses two functional units: (1) per-cell manufactured and (2) per-Wh of storage capacity. The results identified the battery’s production as the highest carbon intensity phase, being the energy usage the main contributor to GWP. In general, the materials and process involved in the manufacturing and recycling of the novel battery achieve a lower environmental impact in comparison to the Li-ion technology. However, due to the Al-ion’s low energy density, a higher amount of materials are needed to deliver equivalent performance than a Li-ion.

The authors wish to make the following corrections to this paper