Report

Teaser, summary, work performed and final results

Periodic Reporting for period 2 - Cell3Ditor (Cost-effective and flexible 3D printed SOFC stacks for commercial applications)

Teaser

The implantation of efficient and clean technologies for energy production is currently a major issue. Solid Oxide Fuel Cell (SOFC) are highly efficient systems converting chemical energy stored in a fuel into electricity and usable heat. Being a ceramic-based multi-layer...

Summary

The implantation of efficient and clean technologies for energy production is currently a major issue. Solid Oxide Fuel Cell (SOFC) are highly efficient systems converting chemical energy stored in a fuel into electricity and usable heat. Being a ceramic-based multi-layer device, its fabrication involves expensive and time-consuming multi-step manufacturing processes and several high-temperature thermal treatments. In addition, these cells are manually assembled into stacks resulting in extra steps for joining and sealing. This manufacturing stages difficult the standardisation and quality control of the final product while introducing weak parts likely to fail. Since current ceramics processing presents strong limitations in shape and extremely complex design for manufacturing (more than 100 steps), industrially fabricated SOFC cells and stacks are expensive and present low flexibility and long time to market. The Cell3Ditor project addresses the main challenge of improving production processes of SOFC systems by introducing novel manufacturing technologies such as 3D printing of ceramics. The project develops 3D printing technology for mass manufacturing of SOFC cells and stacks with the final aim of reducing costs and time to market and simplifying the design for manufacturing while giving flexibility to the final product (strongly required for the heterogeneous commercial segment).

The main goal of Cell3Ditor project is the development of a 3D printing technology for the industrial production of SOFC stacks. To achieve this, several intermediate steps has to be accomplished, including:
• Formulation of printable inks and slurries of SOFC materials
• Development of a 3D printer for multi-material ceramics:
• Fabrication of SOFC cell parts by 3D printing
• Two–step fabrication of joint-free 3D printed SOFC stack ready for integration in systems.

The Cell3Ditor project aims the higher possible impact in society by offering critical technological solutions contributing to the change of the current SOFC production schemes. The proposed Dual 3D ceramic printing technology aims to significantly reduce the costs of fabricating devices, approaching manufacturing capabilities to small and medium companies. This reinforcement of the European industrial fabric would lead to the generation of new business opportunities and jobs. Moreover, the peculiarities of the proposed technology will demand workers with singular technical skills and will open a field for creativity.

Work performed

The Cell3Ditor Project has worked in the main objectives devised for achieving the final goal of defining new manufacturing paragons for the fabrication of SOFCs.

Firstly, definition of final specification of the system to be 3D printed based on Finite Elements Simulations (FEM) was carried out. In parallel, slurries of YSZ for 3D printing and inks of nano-composites for inkjet printing have been fabricated. The production of materials for the inks, i.e. LSM (cathode) and YSZ-NiO, are carried out with the industrially scalable manufacturing technique. Printed pieces and layers of the produced materials have been tested and characterised morphological, compositional, structural and electrochemically.
A second objective is the development of a unique device for 3D printing multi-materials. Three main goals are tracked: the hybridisation of SLA 3D printing machine with an inkjet printer in a unique device, multi-material deposition of 3D parts and the optimisation of the post-printing processes of 3D printed multi-material objects. Bearing in mind the hybridisation and the multi-material deposition, specification of the overall manufacturing requirements of the final system was performed. Subsequently, selection of the inkjet print-head to be installed was made and the mechanical upgrade of the 3D printing machine was designed. Afterwards, installation of a robotic arm with the inkjet head attached took place and first trials ensuring the feasibility of the multi-material printing were carried out. Additionally, software was upgraded as well.
First, Inkjet deposited films show very promising features for the fabrication of SOFC parts. However, some limitations related with the specifications of the final stack discarded Inkjet printing for this purpose. Robocasting technology has been selected instead. Currently, the hybrid multi-material 3D printing machine is fully operative and it is being tested for producing pieces. An important work is being developed for the optimisation of the different post-printing treatments, i.e. cleaning, debinding and sintering. The results obtained allow applying modifications on the heat treatments required: decrease maximum temperature, increase heating ramps, eliminate intermediate steps, etc. First SOFC parts have been produced and characterised.
Taking into account the innovative technology developed in the Cell3Ditor project, dissemination has received a major attention. The fruits of these efforts are visible in the impact generated in the social networks: 440 followers in Twitter, 80 followers in ResearchGate and more than 1800 visits to the web from around the world. The progress of the Project has been presented in more than seven specialised events (congresses, fairs and workshops).
Finally, attention has been paid in finding the best routes for a successful exploitation of the developed technologies. Two secondary market analyses have been performed looking for the best possible approach to the market. The patent landscape and freedom-to-operate scenario is kept updated. In this context, three patents have already arisen fruit of the project developments.

Final results

The ambition of the Cell3Ditor project is the development of 3D printing of ceramics for mass production of SOFC stacks to: i) reduce the cost and initial investment required; ii) increase the SOFC design flexibility; iii) simplify the fabrication process; iv) shorten the time-to-market; v) reduce (waste) material. The simplicity of the Cell3Ditor technology for shaping the whole stack in a single multi-material 3D printing process will drastically reduce the number of fabrication steps. This will simplify the design for manufacturing, reducing the time-to-market from years to months and increasing the adaptability and flexibility of the SOFC stacks. The goals are clearly aligned with the implantation of a circular economy and present an opportunity of generating new business and highly specialized jobs.

The ambition of the Cell3Ditor project is to combine complementary aspects of SLA and inkjet techniques in a single 3D printer ready for approaching the market and especially designed to the fabrication of SOFC parts and stacks. This development will include the multi-material 3D printer, the required functional materials in printable form (inks and slurries) and the final single-step sintering of the whole stack. On the other hand, it is the aim of the project to enhance the range of materials available for being used in different additive manufacturing techniques which currently is limited. It is an important goal of the Cell3Ditor Project to develop slurries and inks of different materials capable to be fabricated by mass production processes. The successful results on the first part of the project must lead to the development of functional parts and a complete SOFC device, showing the community the feasibility of the proposed manufacturing approach.

Website & more info

More info: http://www.cell3ditor.eu/.