Energy: New calcium-ion batteries for electric mobility and smart grids

New calcium-ion batteries, as an alternative to lithium-ion ones for applications in electric mobility and energy storage in smart grids, will be developed as part of the “ACTEA” project, conducted by ENEA and Sapienza University of Rome (coordinator) and funded by the Lazio Region. The team of researchers aims to develop new generation electrochemical storage systems characterized by low production costs and increasingly higher efficiency, sustainability and safety standards, paving the way for a new industrial supply chain along the entire value cycle, from production of raw materials to recycling of spent components at the end of their life.

 “Calcium-ion technology is still in its early stages of development and the objective is to contribute to a better understanding of how it works even if the underlying electrochemical processes are analogous to those of lithium batteries -ion where, however, calcium replaces lithium in the role of charge carrier", explained Laura Silvestri, researcher at the Energy Storage, Batteries and Technologies for Production and Use of Hydrogen Laboratory of the ENEA Department of Energy Technologies and Renewable Sources.

The project delves into unexplored areas, but the key advantages are already clear: calcium is a promising option to increase the energy densities of batteries while cutting production costs thanks to the low cost of raw material^[1] and, above all, its abundance in the earth's crust^[2]. “The development of electrochemical calcium-ion storage technologies will make it possible to overcome the main critical issues related to supply, safety and production costs, providing an eco-sustainable alternative to lithium-ion systems, a mature storage technology that has almost reached its theoretical limit of performance", said Silvestri.

ACTEA's design methodology focuses on the development of processes and materials with a low environmental impact and the use of very common elements like iron, silicon or titanium (in addition to calcium), minimizing the use of toxic and critical raw materials like cobalt and lithium. “This strategy could innovatively and sustainably represent the scenario of a transition from a technological paradigm with a high environmental impact (lithium-ion batteries) to a new, greener one (calcium-ion batteries).

Furthermore, the introduction of calcium and related materials into the battery value chain would open a new market for all producers of traditional raw materials like calcium carbonate and calcium oxide, widely used in construction and pigments”, concluded Giulia Monteleone, head of the ENEA Energy Production, Storage and Use Division of the ENEA Energy Technologies and Renewable Sources Department.