European Commission logo
English English
CORDIS - EU research results

Programme Category


Article available in the following languages:


Strongly improved, highly performant and safe all solid state batteries for electric vehicles (RIA)


Activities should develop further the current solid state battery technology and present solutions beyond the current state-of the art of solid state electrolytes that are suffering from various issues, e.g. a too high operating temperature, too low ion conductivity, too high impedance of the electrode electrolyte interface, short cycle life and lack of knowledge of suitable production technologies at a competitive cost. The ideal solid state battery and electrolyte would provide a solution for all these shortcomings.

Three dominant categories of electrolyte materials seem to emerge:

  • Inorganic electrolyte materials :
    • Inorganic crystalline materials (e.g. perovskites, garnets, sulphides, Nasicon, e.g. suffering from high interfacial resistance and poor interface contacts, problems during cell assembly and/or cycling due to reactivity between solid electrolyte and electrodes);
    • Inorganic amorphous materials (e.g. LiPON, glass oxides).
  • Solid polymers/polymeric materials (e.g. polyethylene oxide, PIL, single-ion, e.g. suffering from low ionic conductivity, electrochemical stability, not suitable working temperature, Li dendrites) ;
  • All solid state hybrid systems (e.g. suffering from low polymer stability at high voltages, and/or knowledge on details and behaviour of the interface in the composite).

Solid state technology, according to a recent stakeholder proposal, has been classified in 2 sub-generations:

  • So called generation 4a with conventional Li-ion materials (as NMC/Si to be developed by 2020-2022) and
  • So called generation 4b with Li-metal as anode (to be developed by 2025-2030)

This call addresses all three main categories of electrolyte materials mentioned above, and includes also solid state batteries of the so-called ""post Lithium-ion"" batteries (generation 4a and 4b), as e.g. solid state forms of Li-S or Li-air.

The work should include:

  • Cell design;
  • Identification of problems and proposals of solutions to overcome issues hampering an optimal function of the specifically proposed electrolyte material(s) at bulk, surface, interface and grain boundary levels;
  • In depth interface optimization, characterization and integration, including multiscale modelling which should target in particular problems of the ion transport processes at the interfaces of the solid state battery system;
  • Demonstration of suitability to work with high voltage electrode materials, where applicable;
  • IP protection and know how creation. A solid analysis and description of the state of the art of specific R&I and the patent situation has to be included.

The developed cells should meet the typical EV operating conditions in a broad temperature range, i.e. 10 to 50 ºC. Moreover, the cells should demonstrate negligible loss of charge during lengthy standby periods at sub-zero temperatures. Fast charging requirements of BEV should be met. Cyclability should be suitable for application in BEV.

The choice of the electrolyte to be developed should be duly justified in terms of chances of market success in the coming years. Validation of a pre-industrial prototype in relevant industrial environment should include an assessment of the scale-up potential in view of large scale manufacturability.

The TRL level of the project should start at TRL 3 and reach TRL 6 at the end of the project.

The Commission considers that proposals requesting a contribution from the EU between EUR 6 and 8 million would allow this specific challenge to be addressed appropriately. Nonetheless, this does not preclude submission and selection of proposals requesting other amounts.

International developments towards less air pollution and CO2 production are pushing towards a rapid implementation of electrification of transport. In addition, according to market forecasts, a rapid growth of the sales and deployment of battery electric vehicles (BEV) is predicted. Considering the global competition, the rush for better technology implies also the need for a better traction battery technology as a key enabling technology. Europe has to regain its competitiveness in markets that nowadays are dominated by non-European countries. This could occur by developing a new European owned battery technology.

Furthermore, an international tendency of Original Equipment Manufacturers (OEM) is to consider more and more the solid state technology as a solution that could replace the current Li-ion technology based on liquid electrolytes. The reason is the need of higher energy density, but also of inherently safe batteries.

New chemistries, materials and production technologies have to be developed to strengthen the European industrial base, in line with the EU initiatives as the Strategic Energy Technology Plan (SET Plan) Implementation Plan for Action 7 ('Batteries') and in support of the Šefčovič battery initiative “EU Battery Alliance”, to be ready for market deployment by 2026.

This challenge is based on the results of previous calls and stakeholder consultations[[""Innovative batteries for eVehicles Workshop"", 12 May 2017, and

""European Battery Cell R&I Workshop"", 11 - 12 January 2018, European Commission DG RTD]] and is supplementary to the topic published in the Sustainable Transport Challenge of 2019 on “Next generation of high energy density, fast chargeable lithium ion batteries”.

  • For generation 4a, an energy density >350 Wh/kg and >1000 Wh/l, for generation 4b a higher energy density >400 Wh/kg and >1200 Wh/l ;
  • Fast charge rates above 10C with power density values >10000 W/kg as 2030 target;
  • Proven safety;
  • IPR protection guaranteed and demonstrated;
  • Cost euro < 100euro/kWh;
  • The European materials modelling capacity and ecosystem should be increased;
  • The European battery value chain towards cell production in Europe should be strengthened.

Relevant indicators and metrics, with baseline values, should be clearly stated in the proposal.

The proposal has to do a thorough Life Cycle Analysis cradle to cradle and consider recycling as far as possible.

This work contributes to the work developed in the running EC-EGVIA agreement and to EGVI related activities of the “Transport Challenges”.