Skip to main content

Battery DEsign and manuFACTuring Optimization through multiphysic modelling

Periodic Reporting for period 2 - DEFACTO (Battery DEsign and manuFACTuring Optimization through multiphysic modelling)

Reporting period: 2021-07-01 to 2022-06-30

DEFACTO stands for Battery DEsign and manuFACTuring Optimization through multiphysics modelling and it is funded by the European Commission within the framework of the Horizon2020 program. The DEFACTO project aims to understand the battery cell performance and manufacturing process through multiscale and multiphysics models.
The project consortium combines competences in multiple fields of modelling and characterization of lithium-ion battery materials, electrodes and cells. As a result, the effects of the different production parameters and their interactions on the cell performance will be described and better understood, and the information provided by the models and simulation will result in an increase of the production’s overall efficiency, in a decrease of the time necessary to take an idea from its conception to the market and, consequently, in a reduction of the production process time and cost. This approach will be applied to the current G/NMC industrial cells and it will be extended to last generation 3b prototypes (high capacity and high voltage cells with a high Ni-content and a low Co-content with silicon-graphite composite anodes). Characterisation tests will also provide data for model development and validation, and for gaining understanding on manufacturing process parameters and cell ageing mechanisms.
Within the project, the consortium will not only generate significant information and computational tools for the acceleration of the cell development process, but also it will foster an environment that will allow the battery market in Europe to grow and strengthen. The resulting simulation tools will predict optimized cell design and cell manufacturing parameters which will be validated by prototyping and manufacturing data of advanced generation 3b cells. In particular, the validated computational simulations will be a powerful tool to (i) tailor new optimum cell designs, (ii) optimise manufacturing steps of electrode processing and electrolyte filling, and (iii) shape new generation 3b materials. Sensitivity analysis will demonstrate model robustness and reduce the number of experiments needed during cell development. The optimization algorithms will enhance cell performance and durability through optimised designs and manufacturing processes. In addition, one of the multiphysics model developed within the project will be released as an open-source simulation tool, where mechanical and electrochemical ageing mechanisms will be included at a reasonable computational cost.
Regarding the characterization activities, the consortium continues performing both physicochemical and electrochemical characterizations to better understand electrode manufacturing, the electrolyte filling process and to gain understanding on the electrochemical ageing mechanisms of the cells. Electrode and separator microstructures and their related transport properties are investigated by direct 3D imaging methods and indirectly by electrochemical-based analyses. The current work is focused on characterizing the mechanical and electrochemical properties of the materials in full cell configuration to identify the ageing laws. Additionally, the DEFACTO database is continuously enhanced by the ingestion of the new results in the project. In regard to the setups for the simulation of the electrode processing, the DEM and CFD- DEM models simulations published in D3.1 were further refined and parametrized for the utilization in different use cases. For the simulation of the dispersing step, algorithms for generating agglomerate and aggregate structures representing carbon black were tested. First test simulations regarding the structure formation during drying and calendering for the different cell chemistries were carried out and revealed the applicability for the use cases. The main computer codes needed for non-physics based digital reconstruction of electrode microstructures were successfully applied to the cathode material. Concerning the work dedicated to optimizing electrolyte filling processes, the LBM was extended by a homogenization approach, which allows for efficient multi-phase flow simulations in pores on different length scales. An extensive electrolyte filling study by the LBM method was published in Batteries & Supercaps. On the electrode scale, a PNM was established and further developed such that complex pore geometries are considered accurately. Also, preliminary results are in good agreement with simulations using the homogenized LBM, which under certain conditions can be used to study the cell scale. Overall, a multi-scale simulation framework was established. Furthermore, the development of simulation methods to describe the electrochemical, mechanical, thermal, and ageing behavior of the battery cells is under progress. The atomistic simulations have been pushed further to accurately describe the properties of the a-Si phases. The stability of the electrochemical-mechanical coupling of solvers BEST and FeelMath was greatly improved which allows to simulate battery performance while dynamically considering the changing microstructure. An upscaling method have developed to derive from the microscopic bulk properties to the macroscopic electrode-scale characteristics. With the release of code for p4D electrochemical simulations a crucial step was achieved. The optimization study of the cell design is in line with the work programme. So far, the “time-adaptative reduced p4D” tool published in D6.1 can be used for fast battery simulations. The “time and parameter-adaptive ROM optimisation” tool was also published in D6.2that can be downloaded through the DEFACTO website. Another ROM using the sPGD method was developed. Last, the refinement of the optimisation problem is under progress. In terms of manufacturing work, 50 G/NMC cells (60 Ah) were delivered and are currently being tested to identify the ageing laws to provide input data for the models. Concerning the prototype cells, a first batch of cells were manufactured and cycled to promote degradation mechanisms. The aged components are being studied via postmortem analysis. New high-quality coatings are being produced to deliver a final batch of prototype cells, as the former face unexpected behavior. Finally, standardized activities are carried out in two CWA format (D8.10 & D8.11). DEFACTO has been showcased in different events, trade fairs, conferences among others. Also, a second version of the Exploitation Plan contains new information regarding the KERs. A final market assessment was also delivered.
DEFACTO envisages the contribute to accelerate the development of advanced Li-ion battery technology by reducing of resources consumed in the development process (TRL7 to TRL9 in the manufacturing lines) and the overall R&I costs of cell (up to TRL6 in the RTOs, thanks to DEFACTO simulation ecosystem. The impact on the standardization landscape, supporting DEFACTO roll out in Europe, is the last expected impact addressed. The work of the DEFACTO consortium will take the research and innovation processes on cell development a step further, optimizing their design and functionality, and increasing the competitiveness of the European industry of electric vehicles.
Summary of DEFACTO project