The Re-cell project focuses on developing materials capable of storing energy while simultaneously reducing aircraft weight. The initiative concerns the development of supercapacitors and structural batteries based on recycled carbon fibre, which can store energy while also forming part of the aircraft structure. The work is being carried out by a consortium comprising Sofitec, AimPlas and I2con and is to culminate in the validation of a full-scale demonstrator linked to the aircraft landing gear assembly. The project addresses two major challenges facing the aviation sector, weight reduction and improved energy efficiency, both of which are crucial as the industry moves towards more sustainable operating models. In this case, the use of multifunctional materials is intended to change the approach to designing aeronautical components by combining mechanical properties with energy-storage capability.
Transport electrification is one of the main routes to reducing CO2 emissions, but in aviation it remains particularly difficult because of battery weight and limitations in energy density. The Re-cell project is intended to address this issue through the development of structural composites capable of storing energy, making it possible to eliminate separate systems and optimise total aircraft weight. As Esteban Castro, R&D engineer at Sofitec, explains, "The main challenge related to aviation electrification is not only to store more energy, but also to do so without increasing weight. Structural batteries make exactly that possible, the component itself performs both a structural and an energy function." According to the project assumptions, these solutions will initially be targeted at non-critical applications such as cabin lighting systems, which is intended to provide a basis for broader integration in the future.
Recycled carbon fibre and multifunctional materials
One of the distinguishing elements of the project is the use of recycled carbon fibre as the basis for developing new materials. This approach is intended both to reduce waste in sectors that make intensive use of composites and to support the development of a circular-economy model in the aeronautics industry. As Fernando Ramos, a researcher in sustainable and future mobility at AimPlas, emphasises, "In the Re-cell project, we are seeking not only to develop new materials with higher efficiency, but also more sustainable ones. We are working to give carbon fibre a second life and transform it into a high-value resource for demanding applications such as aeronautics."
To achieve this, the project is developing advanced fibre recycling and treatment processes, as well as their integration into polymer matrices that are intended to provide structural properties and electrochemical performance at the same time. The scope of work includes not only the development of new materials, but also solving some of the main scientific problems that have so far limited the practical application of structural batteries. These issues include the development of functional solid electrolytes, the variability of the properties of recycled fibres and the complexity of the coupled mechanical and electrochemical behaviour of the material.
Technology modelling and validation
Florin Ardelean, a researcher in computational modelling and simulation at I2con, points out that "One of the project's main advances is the combined approach to phenomena that until now have been studied separately, such as ionic conduction and the mechanical behaviour of the material. This integrated approach is essential to move towards real applications." To meet these challenges, the consortium combines materials design, multiphysics modelling and experimental validation, bringing the technology closer to industrial application.
The project is to culminate in the manufacture and validation of a full-scale aeronautical demonstrator integrated into a component linked to an aircraft landing gear. This stage is intended to make it possible to assess the technology's performance under representative conditions and to serve as a step towards future industrialisation. As Esteban Castro of Sofitec notes, "Developing a real demonstrator is crucial for verifying not only the material itself, but also its processing and integration into industrial aeronautical environments."
Re-cell is part of the 2023 public-private partnership programme, funded by the Spanish State Research Agency, AEI, and co-funded by the European Union. Through this initiative, the project supports the development of new aeronautical applications based on recycled materials. AimPlas contributes expertise in recycling, polymer-material development and advanced-composite manufacturing. I2con is responsible for the development of numerical models used to design and optimise the solution, while Sofitec leads industrial validation.
