Fuel cell stack with comprehensive cross-cocurrent-convection optimization characteristic

Abstract

The invention discloses a fuel cell stack with a comprehensive cross-cocurrent-convection characteristic. The fuel cell stack comprises a fuel inlet main pipeline, a fuel outlet main pipeline, two groups of air inlet main pipeline channels, two groups of air outlet main pipeline channels, a stack top cover, cell units, connecting pieces and a bottom cover, wherein the fuel outlet main pipeline, the fuel inlet main pipeline, air outlet main pipelines and air inlet main pipelines are respectively arranged on different side edges; parallel snake-shaped channels are arranged on a fuel side; and a disperse columnar straight channels are arranged on an air side. Therefore, a comprehensive cocurrent and convection mode between fuel and air is formed. The two groups of air main pipelines are oppositely arranged; the first group of air main pipelines supplies the air to the fuel cell units in odd layers; the second group of air main pipelines supplies the air to the cell units in even layers; relative flowing exists between the adjacent cell units; and the first group of air inlet / outlet main pipelines and the second group of air outlet (inlet) main pipelines are alternately arranged to ensure good heat exchange. Structures of all the connecting pieces in the stack are identical except the top cover, so that performance improvement and processing simplification requirements are met.

Description

technical field [0001] The invention relates to the field of solid oxide fuel cells. Background technique [0002] A fuel cell is a power generating device that converts the chemical energy of reactants directly into electricity. As an efficient, clean and stable energy technology, its biggest advantage compared with the traditional power generation type is that it avoids the combustion process and directly converts the chemical energy of the fuel into output electric energy, and its energy conversion efficiency is not affected by the "Carnot cycle". limits. [0003] Solid oxide fuel cell (SOFC) is one of the most commercial potential types among many fuel cells. Its main advantages include: it has a fuel efficiency as high as 50-60%, and its products are mainly water and high-quality waste heat. The total efficiency of secondary utilization can be as high as more than 80%; the output power is large, the operation is stable and noiseless; the source of fuel is flexible, no...

AI Technical Summary

Problems solved by technology

However, it should be pointed out that since the fuel and air main pipes are closely distributed on the same side of the stack, it is difficult to ensure the total inlet pipe under the parallel flow model, except for the sealing problem between adjacent fuel and air main pipes. The cross-sectional area is always smaller than the cross-sectional area of ​​the outlet main pipe, which will greatly reduce the fluid distribution quality of the fluid between the battery cells (stack level)

In addition, the following typical features are also obtained by referring to the currently reported fuel cell stack structural design schemes: 1) In general stack design, the cathode and anode connectors often use the same connector shape design, which often fails to combine fuel and anode. The different flow and electrochemical working characteristics of the air side are designed; 2) the general stack design often adopts the scheme of a single set of air flow channels, which is not conducive to the uniform distribution of the stack temperature. The research results show that due to the high molar mass of the air, The utilization rate is low, so the air flow is the main heat-carrying fluid inside the stack, and the temperature rises sharply along the direction of the air flow

Images