The project is framed within the transformation of the electricity sector and the improvement of the efficiency of the use of energy. To this end, it is working on the generation of new materials that go beyond the state of the art of current electrochemical energy storage and thermal storage technologies applied specifically in two areas: alternative batteries to lithium-ion for stationary storage and thermal storage technologies applied to heat pumps.

Stationary electrochemical storage technologies beyond lithium-ion

As we all know, battery energy storage is considered key to the development of the electric grids of the future. The use of batteries makes it possible to decouple the generation and consumption of electrical energy, being fundamental for grid integration with renewable energies, as well as to provide the grid with greater reliability, autonomy, stability and lower cost.

Lithium-ion batteries are undoubtedly the dominant technology in the market today due to the significant reduction in cost in recent years. However, this technology still has some technological and economic challenges to overcome to cover all the storage needs of the grid.

That is why, at CIC energiGUNE, we are researching alternative technologies to lithium-ion in order to meet the demand of the stationary sector.

Specifically, the CICe2020 project is working on three lines of research applied to the stationary sector: materials and behavior of sodium batteries, development of materials for metal-air batteries and research on a new generation of redox-flow batteries based on an aqueous organic electrolyte.

The research on sodium-ion batteries that is being carried out is focused on the development of materials that improve the electrochemical performance of this type of batteries, and on the control and optimization of the processing and cell prototyping of these materials that, even today, still face important challenges.

Regarding the research line focused on the development of metal-air batteries (M-O₂), from CIC energiGUNE, we have carried out the research of materials as well as the optimization of the different components of this type of batteries (cathode, electrolyte and anodic protection).

The third line of research within the axis of stationary electrochemical storage technologies corresponds to the development of a new generation of flow batteries based on aqueous organic electrolyte.

The scientific objective pursued is the research on the development of materials and the optimization of their electrochemical behavior and stability under cycles that will allow obtaining an alternative to Vanadium flow battery technology, and, in addition, that offers real guarantees for sizing a large-scale stationary storage system based on this technology.

The organic electrolyte designed ad-hoc by CIC energiGUNE allows working in a desirable potential window, while increasing its stability and solubility and, therefore, the energy density of the battery, as it is a non-aggressive and environmentally friendly aqueous support medium, which improves the performance and durability of the rest of the cell components (membrane and electrode).

Thermal storage technologies for improving heat pumps

The power generation and heating and cooling sectors play an important role in the transformation to a low-carbon economy.

The use of heat pumps combined with thermal energy storage is internationally recognized as the best technology to efficiently connect both sectors. It is a key technology for the decarbonization of the heating sector, as well as contributing to the development of low-cost alternative solutions to the use of fossil fuels and favoring the use of clean energy sources.

In line with the axis of thermal storage technologies within the CICe2020 project, we have carried out research on the new generation of solid-solid phase change materials for thermal storage.

This working line aims to contribute to the future development of new thermal storage systems for domestic or industrial heat pumps that will allow progress in the electrification of heat.

The research developed will make it possible to drastically reduce the volume of storage tanks and/or their investment costs.

Collaboration:

Elkartek CICe2020 has the leadership of CIC energiGUNE as a reference center in energy storage, and the participation of other BRTA centers such as Tecnalia, Tekniker, Ikerlan and Cidetec, the UPV/EHU and MU-EPS universities and the BERC Polymat center.