Periodic Reporting for period 2 - Hydra (Hybrid power-energy electrodes for next generation lithium-ion batteries)
Periodo di rendicontazione: 2021-11-01 al 2023-04-30
HYDRA aims to develop the next generation of commercially viable Li-ion battery cells based on sustainable materials and manufacturing processes. Within the roadmap for future battery development, these Li-ion battery cells are referred to as generation 3b. They aim to increase the energy density of the cells by developing new materials, while also reducing the critical raw materials (CRM) content by more than 85%. To achieve this goal, high-capacity silicon is blended together with graphite in the anode and cobalt-free lithium nickel manganese oxide (LNMO) and lithium iron phosphate (LFP) materials are used in the cathode.
The problem is that although these materials can improve the energy density of the battery, they typically suffer from accelerated capacity loss over cycling. HYDRA brings together leading industry and research partners to identify novel solutions to extend the cycle life of these cells and support the growing European battery industry. By the end of the project in 2024, HYDRA aims to demonstrate cells with high energy density (>750 Wh/L) and long cycle life (>2000 cycles) while supporting fast charging from 20% - 80% SOC in 8-12 min. Through the development of sustainable and high-performance Li-ion cells, HYDRA will contribute to the future of electric mobility and help support the Green Transition.
Throughout the work foreseen in the project, it is very important to engage with both the European battery community and the public. HYDRA aims to support the community by making as much data as possible available using the FAIR data standards. Furthermore, the modelling tools developed in the project will be made open-source. In the latter phases of the project, HYDRA aims to interact directly with researchers from around Europe via the Access HYDRA program, in which researchers, engineers, or students can apply for short research stays at HYDRA partner institutes to develop skills or knowledge related to the project objectives.
In parallel, work on developing hybrid electrode materials like Si/C and LNMO/LFP was carried out to support the next generation of HYDRA.1 cells. Good material dispersions were achieved, and target performance was reached for each of the materials in half-cells. At the end of the second phase, initial activities were underway to create a batch of multi-layer pouch cells for the HYDRA.1 generation.
A technoeconomic analysis of the impacts of the HYDRA project was carried out to estimate the cost and relative benefits of the HYDRA approach. It was determined that the aqueous cathode processing could lead to significant reductions in the cost of cell manufacturing. Aqueous processing not only removes the need for NMP solvent in the cathode slurry, but also much of the supporting equipment dedicated to NMP recovery and processing. In this way, aqueous processing could be beneficial for both the ecological sustainability and economic viability of the HYDRA cells. The HYDRA partners have also participated in a Battery Ecodesign Workshop to learn methods for integrating sustainability considerations into battery development and identify critical areas of battery development that could greatly benefit from Ecodesign considerations.
The final phase of the project will focus on manufacturing the HYDRA.1 and HYDRA.2 generations of cells on the pilot scale, with the aim of demonstrating the project KPIs.
The development of cathode materials in HYDRA seeks to circumvent the problems that have so-far limited the performance of high-voltage spinel materials like LNMO. HYDRA's approach of using surface treatment layers on LNMO to increase cell power and to avoid cation dissolution is environmentally friendly, and the performance goals will be reached with no use of the CRM cobalt. Strong focus on the scalability of the approach will maximize the chances of industrial realisation.
Anode material development in HYDRA will seek to maximize the capacity of the electrode by blending significant amounts of Si with graphite. HYDRA will develop composites with low area/volume ratio and high cycling stability. In an optimised binder-system, these composites will give high energy density with the required cycling stability necessary for industrial relevance. The use of synthetic graphite reduces the reliance on mining natural graphite, which is a CRM.
Electrolytes must be able to support the unique processes at both electrodes while also being very stable and highly ionically conductive. HYDRA will develop new electrolyte systems that function at the high working voltages of our proposed high voltage cathode materials, while also being compatible with the Si-graphite anode by passivating the Si surface from continuous electrolyte reduction.
As giga-scale production of batteries is growing across Europe, the use of sustainable manufacturing processes is more important than ever. HYDRA will develop solutions for all-aqueous based electrodes for Li-ion HYBRID batteries and demonstrate them in pilot scale. The water-based chemistries will reduce the need for dry-rooms, decreasing manufacturing energy consumption. This will provide the environmentally friendly and economically sustainable production processes necessary to obtain the high energy, generation 3b Li-ion batteries necessary for a decarbonised Europe.
Taken together, these individual improvements on the state of the art will lead to a new generation of Li-ion battery cells with not only beyond state of the art performance KPIs for energy density and cycle life, but also sustainably based manufacturing processes and model-accelerated development workflows. This is essential to establishing a successful and environmentally friendly battery industry in Europe. In pursuit of this goal, HYDRA will also educate the up-and-coming generation of scientists and engineers by supporting students, post-docs, and early career researchers in the project. As the demand for batteries increases around the world, HYDRA will position European society to benefit from the Green Transition in terms of education, jobs, access to clean energy, and improved environmental quality.