Development Of Multi-physical Field Coupled Model And Performance Investigation Of Microfluidic Fuel Cell

Microfluidic fuel cell(MFC)has a promising future with the advantages of small size,portable structure,sustainable operation and lower pollution.Generally used to power portable electronic equipment,such as medical test paper.One of the main reasons restricting the commercialization of MFC is the limited output power density and voltage.To meet the requirements of miniaturized electrical equipment in practical application,structure of MFC which can be further assembled into cell stack is proposed in this paper.A multi-physical field coupling model is established to numerically solve the dual-cell and its cell stack.The research results are helpful to reveal the basic mechanisms of MFC convection-diffusion-reaction process and then provide significant theoretical suggestions for the practical applications.This paper puts forward H-shaped self-breathing dual cell structure.A coupling model of mass transfer,diffusion and electrochemical reaction is established.And the model is validated by an experimental of breathing formic acid MFC building by soft lithography and laser processing.The influence of electrode morphology and amount on single MFC is studied and the operation rules of single and dual MFC is summarized.This study clarifies the advantages of asymmetric electrode in MFC and gain the maximum power density of 7.72 m W/cm~2.The performance of single MFC was improved effectively.By incorporating adjacent entrance,effectively assemble the cell stack with the parallel and series model is established.Output performance and fuel efficiency of cell stack are compared and the mechanism of cell stack construction and operation is clarified.In this study,a flow-along and flow-inverse single modular MFC structure is proposed.Two cell structures with the same size but different electrolyte crisscross are created.Four basic single cell structures are constructed according to the flow direction of electrolyte and the position of anode and cathode electrodes.Flow-over electrode structure numerical simulation model which combines the transfer and diffusion of substances as well as the electrochemical reaction is established and calculated.The working rules of four basic single cell structures under different operating conditions are studied.Suggestions and opinions for the actual use of cells are summarized.Structure of the cell stack is further discussed.Depending on the number of the cell stack,in turn,double cell stack and treble cell stack are established as an example.Output current density of single cell and cell stack under different reaction conditions is studied combined with fuel efficiency as well as the distribution of reactants between individual cells within the cell stack.Modular MFC stack assembly is flexible and provides users high freedom when operation.Based on the results of the model,the basic rules and reasonable suggestions for cell stack assembly are put forward.All these discussions provide references for the design,assembly and application of MFC stacks in the future.