A Numerical Simulation of Evolution Processes and Entropy Generation for Optimal Architecture of an Electrochemical Reaction-Diffusion System: Comparison of Two Optimization Strategies

Employment of electrochemical energy devices is being expanded as the world is shifting toward more sustainable power resources. To meet the required cost efficiency standards for commercialization, there is a need for optimal design of the electrodes. In this study, a topology optimization method is proposed to increase the performance of an electrochemical reaction-diffusion system. A dimensionless model is developed to characterize the transport and rate processes in the system. Two optimization strategies are introduced to improve system performance using a heterogeneous distribution of constituents. In addition, an entropy generation model is proposed to evaluate the system irreversibilities quantitatively. The findings show that the system performance could be enhanced up to 116.7% with an optimal tree-root-like structure. Such a heterogeneous material distribution provides a balance among various competing transport and rate processes. The proposed methodology could be employed in optimal design of electrodes for various electrochemical devices. This study also offers a fundamental comprehension of optimal designs by showing the connection between the optimal designs and the entropy generation. It is revealed that a less dissipating system corresponds to a more uniform current and entropy generation. Some recommendations are also made in choosing a proper optimization approach for electrochemical systems.