Optimization of interconnect flow channels width in a planar solid oxide fuel cell Xiaolian Li a,b , Wangying Shi a,b , Minfang Han a,b,* a Department of Energy and Power Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing, 100084, PR China b Tsinghua Innovation Center in Dongguan, Guangdong, 523808, PR China article info Article history: Received 16 May 2018 Received in revised form 21 August 2018 Accepted 11 September 2018 Available online xxx Keywords: Solid oxide fuel cell Interconnect flow channels Simulation Channel width abstract Finite element analysis is an effective method to investigate the uniformity of species distribution in solid oxide fuel cells. This paper presents a 3-D model with coupled mass transport, electron transfer and electrochemical reaction. Based on a working anode- supported SOFC with gas channels and porous electrodes, the model is validated by measured IeV curves. The simulated results deviate no more than 3% from the measured data and indicate significant dependency of current density distribution on the gas composition distribution. Meanwhile, the simulated results also indicate that the ridges of the interconnect have negative effects on electrochemical reaction due to the limitation of mass transport. In further study, cases of various channel widths are calculated and analyzed, finding that the optimal width ratios for electrochemical in cathode and anode are 0.5. © 2018 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. Introduction Solid oxide fuel cell is a device that directly converts chemical energy to electricity at high electric efficiency and with low emission. As an electrochemical reactor, the distribution of species, electron and heat directly affects the electrochemical performance of a SOFC [1]. Regions with high reactant con- centration show high reaction rates and thus high current density and temperature. While the sites lacking of reactants have limited reaction rate [2,3]. Secondly, the variation in temperature induced by non-uniform distribution of species significantly contributes to the deterioration of materials in long-term operations [4e8]. It is important to ensure the uni- formity of species and temperature. The studies found that the species transportation and distribution in fuel cells strongly depend on the design of electrodes, interconnector and the external manifold [5,6,9e11]. Zeng et al. [12], Huang et al. [13] explored the effects of anode porosity on thermal stress and found that increased porosity resulted in decreased von mises stress. Zhao et al. [14] constructed a model to investigate the in- fluence of the external manifold on flow distributions and pressure variations. The results indicated that flow uniformity strongly depends on geometric shapes of the manifold, including gas inlet position and dimensions. In these studies, numerical simulations based on various commercial software were done to investigate the coupled physical process and to suggest geometrical optimization of the cells [9,10]. Considering the high costs and long time * Corresponding author. Department of Energy and Power Engineering, State Key Laboratory of Power Systems, Tsinghua University, Beijing, 100084, PR China. E-mail address: hanminfang@mail.tsinghua.edu.cn (M. Han). Available online at www.sciencedirect.com ScienceDirect journal homepage: www.elsevier.com/locate/he international journal of hydrogen energy xxx (2018) 1 e11 https://doi.org/10.1016/j.ijhydene.2018.09.061 0360-3199/© 2018 Published by Elsevier Ltd on behalf of Hydrogen Energy Publications LLC. Please cite this article in press as: Li X, et al., Optimization of interconnect flow channels width in a planar solid oxide fuel cell, In- ternational Journal of Hydrogen Energy (2018), https://doi.org/10.1016/j.ijhydene.2018.09.061