Unlock instant, AI-driven research and patent intelligence for your innovation.

Preparation method of diffusion layer used for reducing phosphoric acid loss in high-temperature fuel cell

A diffusion layer and microporous layer technology, applied in battery electrodes, battery components, circuits, etc., can solve the problems of PEMFC fuel cell performance degradation, battery performance degradation, etc., to prevent the loss of phosphoric acid, improve performance and stability Effect

Active Publication Date: 2019-06-25
DALIAN INST OF CHEM PHYSICS CHINESE ACAD OF SCI
View PDF2 Cites 2 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

Therefore, phosphoric acid plays a very important role in the high-temperature fuel cell of the PBI membrane system. If a large amount of phosphoric acid is lost during the application process, the performance of the battery will inevitably decrease. Document 1 reports that the performance of high-temperature PEMFC fuel cells will be greatly reduced when the loss of phosphoric acid is serious.

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Preparation method of diffusion layer used for reducing phosphoric acid loss in high-temperature fuel cell
  • Preparation method of diffusion layer used for reducing phosphoric acid loss in high-temperature fuel cell
  • Preparation method of diffusion layer used for reducing phosphoric acid loss in high-temperature fuel cell

Examples

Experimental program
Comparison scheme
Effect test

Embodiment 1

[0025] Toray060 carbon paper is treated with 5wt% PTFE emulsion hydrophobically, and the PTFE content in the carbon paper is 7wt%, and it is used after heat treatment at 340°C. XC‐72, 30wt% PTFE emulsion and ethylene glycol prepared microporous layer slurry 1 at a ratio of 1:1:10, XC‐72, 30wt% PTFE and ethanol prepared microporous layer slurry 2 at a ratio of 1:1:20 . The slurry 1 is scraped on the surface of carbon paper by scraping method, and the carbon powder loading is calculated as 0.5mgcm ‐2 That is, after drying, scrape the slurry 2, and scrape it several times until the carbon powder loading is 2mgcm ‐2 . After heat treatment at 340°C, it can be used to prepare the catalytic layer. figure 1 ‐4 is the scanning electron microscope image of the microporous layer obtained during the four coating processes in turn. It can be seen from the figure that the pore size of the microporous layer gradually decreases during the multiple coating processes. The prepared diffusion...

Embodiment 2

[0027] Toray030 carbon paper adopts 7wt% PTFE emulsion to hydrophobically treat, and the PTFE content in the carbon paper is 10wt%, and it is used after heat treatment. Microporous layer slurry 1 was prepared with BP2000, 30wt% PTFE emulsion and ethylene glycol at a ratio of 1:1:15, and microporous layer slurry 2 was prepared with XC‐72, 30wt% PTFE and n-butanol at a ratio of 1:1:30. Print slurry 1 on the surface of carbon paper by screen printing, and weigh and calculate the carbon powder load to be 0.4mgcm ‐2 That’s right, after drying, print slurry 2, and print multiple times until the toner loading is 1cm ‐2 . After heat treatment, it can be used to prepare the catalytic layer. The prepared diffusion layer can reduce the loss of liquid electrolyte phosphoric acid used to conduct protons in the high-temperature membrane and catalytic layer during the operation of the high-temperature fuel cell, thereby improving the performance and stability of the high-temperature fuel c...

Embodiment 3

[0029] Toray120 carbon paper adopts 3wt% PTFE emulsion to hydrophobically treat, and the PTFE content in the carbon paper is 5wt%, and it is used after heat treatment. XC‐72, 30wt% PTFE emulsion and glycerol were prepared in the ratio of 1:1:20 to prepare the microporous layer slurry 1, and acetylene black, 30wt% PTFE and isopropanol were prepared in the ratio of 1:1:40 to prepare the microporous layer slurry 2. Print slurry 1 on the surface of carbon paper by screen printing, and weigh and calculate the carbon powder load to be 0.3mgcm ‐2 That’s right, print the slurry 2 after drying, and print multiple times until the toner loading is 2.5cm ‐2 . After heat treatment, it can be used to prepare the catalytic layer. The prepared diffusion layer can reduce the loss of liquid electrolyte phosphoric acid used to conduct protons in the high-temperature membrane and catalytic layer during the operation of the high-temperature fuel cell, thereby improving the performance and stabi...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

PUM

No PUM Login to View More

Abstract

The invention relates to a preparation method of a diffusion layer capable of reducing the phosphoric acid loss in a high-temperature fuel cell. The method comprises the steps of base material pretreatment and slurry and microporous layer preparation. The diffusion layer prepared through the pretreatment of a base material, the optimization of slurry and the improvement of the preparation method can reduce the loss of a liquid electrolyte used for conducting protons, namely, phosphoric acid, in a high-temperature membrane and a catalysis layer in the operation process of the high-temperature fuel cell, thereby improving the performance and stability of the high-temperature fuel cell. The porosity and pore size distribution of the diffusion layer are controlled through the slurry and the preparation method so as to obtain a diffusion layer which prevents the loss of phosphoric acid in the catalysis layer while ensuring the gas transmission. In the method, the base material is various types of carbon paper and carbon cloth, and the pretreatment of the base material is hydrophobic treatment. The microporous layer is prepared on the surface of the hydrophobically treated base material,the preparation of the microporous layer adopts carbon powder and PTFE slurry which are different in viscosity and solid content, and the microporous layer is prepared by means of coating for multiple times.

Description

technical field [0001] The invention belongs to the technical field of high-temperature fuel cells, and in particular relates to a method for preparing a diffusion layer for reducing phosphoric acid loss in high-temperature fuel cell applications. Background technique [0002] High-temperature (120‐200°C) proton exchange membrane fuel cells have gradually become a research hotspot in recent years due to their high resistance to CO poisoning, compared with the simple water and heat management system of low-temperature proton exchange membrane fuel cells. Phosphoric acid (H 3 PO 4 ) doped polybenzimidazole (PBI) membrane is recognized as one of the best materials for high-temperature proton exchange membranes, and is currently widely used in high-temperature proton exchange membrane fuel cells. In high-temperature proton exchange membrane fuel cells, PBI membrane itself has no conductivity and the ability to conduct protons. PBI membranes must be doped with phosphoric acid b...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More

Application Information

Patent Timeline
no application Login to View More
Patent Type & Authority Applications(China)
IPC IPC(8): H01M4/88H01M2/14
CPCY02E60/10Y02E60/50
Inventor 王素力景粉宁孙公权
Owner DALIAN INST OF CHEM PHYSICS CHINESE ACAD OF SCI