What is required for automated assembly and non-destructive disassembly of fuel cell systems at the end of their product life ?

03/16/2023

Source: Energy & Management Powernews

How can fuel cells be installed in such a way that they can be dismantled and reused without destruction? This is what researchers in the "Stack2P" alliance are investigating.

Intelligent product design and efficient dismantling processes, according to a recent announcement by the Fraunhofer Institute for Machine Tools and Forming Technology (IWU), are crucial prerequisites for ensuring that as many components as possible from disused fuel cell stacks make it into a second product life. In the "Stack2P" (Stack to Piece) research alliance, four Fraunhofer institutes are now jointly investigating which machines, systems and processes are required to be able to automatically assemble fuel cell systems and to dismantle them again non-destructively at the end of their product life.

The project objective is to develop a comprehensive concept for reuse, refurbishment, repair or - where unavoidable - recycling for all parts and components of the stack. For example, housings should be designed to be reusable. Seals should be largely recyclable in the future.

The goal: mass-produced systems for separating all components

Currently, fuel cell systems are still largely disassembled manually, which is not suitable for efficient future recovery of parts and components on an industrial scale. Disassembly is challenging because a stack consists of multiple fuel cells connected in series. During the non-destructive disassembly of a stack, it is necessary to loosen numerous joining connections while not damaging the bipolar plates, which are no more than 0.1 millimeters thin and enclose the membrane electrode assembly (MEA) inside the cell.

The researchers in "Stack2P" want to look at the entire process chain, from data acquisition (type of stack) to unstacking (removal) and automated separation of all components to removal of the MEA. For this, the project involves:

- the Fraunhofer IKTS (Institute for Ceramic Technologies and Systems), which tests the condition of the fuel cells at the end of their use
- the Fraunhofer IST (Institute for Surface Engineering and Thin Films): It is developing a recycling line and sustainable recycling concepts for PEM fuel cells. Thereby a focus is on chemical processes for the disassembly of the MEA to recover the precious metal platinum.
- the Fraunhofer IWU: It develops the process for mechanical separation of the components, i.e. automated disassembly processes including detection and release of joint connections. It also designs guidelines and processes for product and production. For this purpose, the IWU in Wolfsburg, together with the industrial partner Aumann Limbach-Oberfrohnau GmbH, is setting up a research facility for the fully automated disassembly of fuel cell stacks
- The Fraunhofer IFAM (Institute for Manufacturing Technology and Applied Materials Research) is simultaneously setting up a destacking module at the Bremen site to gain knowledge about adhesive joints.

On completion of the project, it should be possible to develop series plants for the separation of all components of a fuel cell system by type on an industrial scale. The project is part of the National Fuel Cell Production Action Plan (H2GO).

Author: Katia Meyer-Tien