Polymer electrolyte membrane fuel cell research stack

Anovion developed and built a Polymer Electrolyte Membrane Fuel Cell (PEMFC) stack for research and development purposes. In order to enable a fast-pace development without expensive and cumbersome hardware test-design iterations, Anvion’s model-based design framework was employed. Here, the physical behaviour of the stack and its underlying components is modeled and resolved by means of numerical simulations. Thermodynamic sizing, integral system design and detailed component design are carried out in an iterative manner until benchmark analyses results are achieved. The purpose of the stack is to conduct research and development for next generation fuel cell technologies. The specific areas of utilization are multi-fold. For example, the easy de- and reassembly feature allows to test different bipolar plate flow field designs or novel materials associated with the membrane electrode assembly. Also, the stack can serve as a reference product for developing automated manufacturing solutions. Generation of real-world performance data for either developing system identification approachs to extract key physical quantities or for developing self-learning controller are further possible research applications.

Year

2022

Results
  • 2.5 kW PEMFC Research Stack
  • Fully modeled and simulated
  • Utilization possibilities
Collaboration
  • Albert & Hummel GmbH
Background

Fuel cell technologies present one crucial element for successfully transforming our energy generation landscape from predominatnly conventional/fossil to renewable/CO2 neutral. This is mainly due to the potential of fuel cells to convert renewably generated hydrogen into electricity (and heat) in a highly efficient manner. However, a sustainable and large-scale establishment of fuel cell technologies has yet to occur, and requires to overcome a few considerable technological obstacles. Thus, further research and development efforts leading respective technological breakthrouhgs are necessary. Specifically, the main areas of fuel cell research are material design of the electrochemically active layers in terms of microscopic efficiency and resistance against degradation, bipolar design for optimal flow fields and flow-MEA interactions as well as system design and control for optimal efficiency. Advancing in these fields yields the potential of achieving high electrical conversion efficiencies, which will imply a strong step towards market competitiveness of fuel cell technology, and the accompanied transformation towards net-zero CO2 energy generation.

Project

Anovion developed a PEMFC research stack employing a hybrid model-based development approach, i.e. designing the stack and all underlying components guided by numerically obtained performance results based on respective physical models. The goal was to develop a robust stack in a short amount of time without the need of experimental prototypes for design iterations and finalization. Specifically, this model-based development approach consisted of five phases:

  1. Definition of integral performance targets. These were the nominal power output along with the operating cell voltage as well as a target efficiency and volumetric power density.
  2. Modeling of integral electrochemical and thermo-fluidic performance yielding electrical currents, flow rates, fuel and air excess ratios, temperature levels and cell power densities. These quantities served as the design targets for the detailed component design.
  3. Sizing and geometrical design of stack components, in particular the bipolar plates including the flow field structure and the membrane electrolyte assembly. This was accompanied by designing the entire stack including fixation concept, flow manifold system, base plates, and current collector.
  4. Numerical simulations based on the available physical models of the components and the entire stack to iteratively adapt the respective CAD designs. These iterative design adaptions were carried out until respective simulations results satisfied predefined benchmarks.
  5. Building the stack alongside with the development of a diagnostics kit that allows a rigorous and convenient experimental characterization.

The central outcome of this work is a PEMFC hardware stack of 2.5kW nominal electrical power. One unique feature is the easy to de- and reassembly possibility, which enables to implement and test novel component design of e.g. bipolar plates, unit cells and associated materials.

Conclusion

A research PEMFC stack was developed based on Anovion’s model-based design framework and is readily available for the purpose of developing and advancing fuel cell technologies. Specifically, the stack can be used for experimental characterization in the context of the following research areas:

  1. Development of novel materials for of electrodes and electrolytes
  2. Design and optimization of bipolar plates in terms of flow field and geometrical compactness
  3. Automated production technologies for fast pace industrialization
  4. Data generation and validation for self-learning and adaptive controller designs
  5. Data generation and validation for the development of system identification techniques for degradation mechanisms
  6. Data-generation for training self-learning algorithm

Lastly, the stack is usable as a hands-on device for learning and teaching purposes, e.g. if one seeks to enter the field of fuel cell technology for gaining understanding of the subject.

Anovion research stack integrated into Fuel Cell Stack Test Equipment developed by Noffz Technologies and Albert & Hummel Technologies.