Reliability and durability are key considerations to successfully deploy Proton Exchange Membrane Fuel Cells (PEMFCs). Since the link between materials defects and performances at the scales of the Membrane Electrode Assembly (MEA) and the stack is now well documented, LOCALI shall provide information about the propagation of these defects to other materials or to other locations in the stack. LOCALI aims to improve the existing systems and will ultimately provide effective tools to control their mass-production, the quality of the stacks and their diagnosis for on-site maintenance (stationary) or for on-board (transportation) applications. To these goals, the study focuses on three main axes, developed for PEMFCs (but which can easily be implemented for E-PEM). Firstly, LOCALI will develop instrumentation dedicated to local current density measurement and local electrochemical impedance spectroscopy: well-instrumented segmented cells and magnetic fields measurement are the core competences to these goals. The second challenge of LOCALI is, by using tailored defective MEAs or thanks to specific operating conditions (flooding, reagent exhaustion, ...) to characterize how local and overall performances of the MEA are affected, and to identify the signatures of the various anomalies. Our target is to identify the source of the heterogeneities as well as to locate degraded areas inside a stack. Finally, LOCALI will enable to track, during ageing, how the initial and controlled defects do propagate upon operation. A particular attention will be paid on two points: (i) does a defect in the one material of the MEA (e.g. a hole in the PEM) influence the local degradation of its neighboring materials (e.g. the catalyst layer); (ii) does the defect propagate spatially, and if so, does it happen only at the MEA scale (e.g. from the inlet to the outlet regions) or at the stack scale (i.e. from the defective cell to its neighboring ones).

The market introduction of high temperature wide bandgap power semiconductor devices with junction temperature exceeding 200°C significantly accelerates the trend towards high power density and severe ambient temperature electronics applications. Such evolution may have a great impact in aeronautics applications, especially with the development of More Electric Aircraft (MEA), since it can allow to reduce the mass and volume of power electronics systems. As a consequence, the aircraft operating cost can decrease. However, for electronics used under such harsh conditions, the package reliability and the heat evacuation are very critical issues. The goal of this project is to design and fabricate high performance double sided cooled power electronics modules with optimized thermomechanical properties. The assembly is based on copper joints and a copper heat sink and integrates several technological breakthroughs. Three main technological bricks will be deeply addressed in order to reach the target: 1) Synthesis of nanoporous copper films, either freestanding or directly deposited on metallized substrates with controlled microstructure: In order to limit the risks, three independent strategies will be investigated during the project: the synthesis of nanoporous copper free standing films using melt-spinning and chemical dealloying techniques, the direct on-substrate electroforming of copper-alloy followed by anodic dealloying, and the direct growth of nanoporous structures without any additional treatment by tuning electrolyte formulation and plating parameters. 2) Thermocompression of the nanoporous copper films for die attach: Conventional heating will be achieved at low pressure and in inert/reductive atmosphere. An alternative method based on laser induced fast heating will also be evaluated to thermocompress the nanoporous copper in air. Both solutions allow to limit the oxidation copper issues. The underlying physical mechanisms taking place during the thermocompression of the various morphologies and microstructures of nanoporous copper films will be in-depth investigated. The joint stability under electro-thermo-mechanical aging conditions will be evaluated. 3) Deposition of thick copper layers for substrate/heatsink assembly using electroforming process: A thick dense metal layer will be deposited on a designed sacrificial polymer preform allowing to create a wide range of complex shapes directly on the metallized substrate with low residual stresses. This technology combined to virtual prototyping will allow us to fabricate high performance heat sink patterns (liquid forced convection without phase change) in terms of high local heat transfer coefficient and low pressure drop. The thermal-hydraulic performances of the heat sinks will be analyzed with an experimental setup. The robustness of the assembly (substrate/heat-sink) under repetitive temperature variations will be also evaluated. Silicon Carbide (SiC) devices based power modules (inverter phase leg) using the aforementioned technological bricks will be realized and evaluated in the project. Electrical, thermal and robustness tests are planned to estimate the module performances. The COPPERPACK project will contribute to validate and push our concept from Technology Readiness Level (TRL) 2 up to a TRL 3-4 with a functional technological demonstrator.

The negative capacitance (NC) effect has been presented as a possible solution to the necessary reduction of the switching voltage in field effect transistors and could thus contribute to the future development of low power switching devices. The work that we plan to carry out is mainly positioned in the development of mature static NC structures. This maturity will be reached if we can control and stabilize the physical phenomenon at the origin of this NC. To succeed, it will be necessary to develop heterostructures alternating layers of a few nanometers thick made of ferroelectric (FE) materials on the one hand and paraelectric (PA) materials on the other hand, and to control the quality of the interfaces essential to the stabilization of the NC effect. The choice of materials, the control of epitaxial stresses and electrostatic effects will be crucial to bring the NC phenomenon back to near-ambient temperature ranges. The consortium set up for this project intends to take up this challenge and for that it gathers competences and strengths in the elaboration of heterostructures, the fine characterization at the elementary scale of the materials, of their interfaces, of the structure in ferroelectric domains, the electrical characterization of these structures at the local and macroscopic scale in wide frequency and temperature ranges, clean room technologies for the realization of specific test vehicles. In this context, the objectives of the NEGCAP project are: (i) to fabricate model FE/PA structures in superlattice (for direct measurement of negative capacitance) and multilayer (for indirect measurement of NC), (ii) to determine and model the dielectric response of these structures in a wide frequency range, (iii) to probe the properties at the FE/PA interfaces in order to understand the physical phenomena involved, (iv) to identify the fields of application of these structures and to propose "negative capacitance effect at room temperature" structures.

The context of wide bandgap power semiconductor devices necessitates to reinvent current packaging technologies. An innovative solution, based on the integration of power components within heat sinks, seems to be an excellent candidate to increase the power density of static converters. It is also highly modular, which makes it possible to envisage easier design and maintenance. In the DESTINI project, research works will be proposed to set up electrostatic, electrothermal and electromagnetic modeling methods of this kind of package. Reliability aspects will be addressed through the implementation of tools and methods for the study of damage. Technological works will be carried out to make test setups.

To guarantee the voltage quality at all electric grid levels, the safe and reliable operation and to avoid costly expansion of future electric grids, volatile renewable energy sources and storage systems must be intelligently and informatively connected. The project AI4DG aims to research and develop a distributed AI on the edge platform for an autonomous and secure battery storage control system in low voltage grids with a high share of renewable energy sources using smart meter data. Due to the distributed AI on the edge approach, the system is more fail-safe and able to preprocess sensible smart meter data to ensure data protection regulations than a centralized approach. After project preparations, the partners analyze the AI requirements defined for the energy system and AI methodology for the project. In parallel, the project partners develop a detailed hardware low voltage grid simulation and a cognitive edge architecture for distributed AI to implement and validate the distributed AI system. After successful validation, the AI system will be evaluated in the field. The project results will be disseminated at scientific open access journals and conferences. The partner AtosWorldgrid will review the further development of the project results of the AI on the edge system to achieve market readiness. Due to the AIbattery storage control, costly grid expansions will be minimized in the electric grid of Stadtwerke Versmold