Graphite micro-crystalline carbon coating for metal bipolar plates of fuel cells and application thereof

Patent metadata

Field	Value
Publication number	US-11799094-B2
Application number	US-201916966717-A
Country	US
Kind code	B2
Filing date	Jan 23, 2019
Priority date	Jul 23, 2018
Publication date	Oct 24, 2023
Grant date	Oct 24, 2023

Abstract

The invention relates to a graphite micro-crystalline carbon coating for metal bipolar plates of fuel cells and an application thereof. The graphite micro-crystalline carbon coating is a graphite-like coating deposited on the surface of a metal bipolar plate, includes, by weight, 5%-50% of graphite micro-crystals, and has good compactness. Based on conventional magnetron sputtering technologies, the energy of deposited particles is changed by changing a target sputtering power source, the intensity of a sputtering magnetic field and the deposition temperature of the coating to change the structure of the carbon coating, so that the carbon coating with high conductivity, corrosion resistance, and stability is prepared. Compared with the prior art, under a precondition where the preparation cost of the coating is not increased, the contact resistance of the metal bipolar plate of a fuel cell and a gas diffusion layer can be reduced, and the corrosion resistance of the carbon coating in an acidic environment of the fuel cell and the conductive stability of the carbon coating after a long-time test can be improved, which is of great significance for promoting the commercialization of fuel cells.

First claim

What is claimed is:

1. A graphite carbon coating for metal bipolar plates of fuel cells, being deposited on a surface of a metal bipolar plate, the graphite carbon coating comprising:
amorphous carbon; and
by weight, 5%-50% of graphite micro-crystals, wherein a grain size of the graphite micro-crystals is 1-2000 nm, wherein
the graphite carbon coating having a contact resistance of less than 1.6 mΩ.cm 2 , and the graphite carbon coating is prepared by changing energy of deposited particles during deposition of the graphite micro-crystals and has high conductivity, corrosion resistance, and stability, and
the energy of the deposited particles is 1-100 eV, the energy of the deposited particles is changed by changing a deposition temperature in a coating deposition process, and the deposition temperature is changed to 150-600° C. by means of a heater in the coating deposition process.

2. The graphite carbon coating for metal bipolar plates of fuel cells according to claim 1 , wherein the graphite carbon coating
has a thickness of 1-500 nm, and
the graphite micro-crystals account for 10%-30% of a total weight of the carbon coating.

3. The graphite carbon coating of claim 1 , wherein the graphite carbon coating having an intensity ratio of D peak at 1360 cm −1 over G peak 1580 cm −1 of 3.3.

Assignees

• Univ Shanghai Jiaotong

Inventors

• Peng Linfa
• Li Xiaobo
• Yi Peiyun
• Qiu Diankai
• Lai Xinmin

Classifications

• H01M8/0228 Primary

  in the form of layered or coated products · CPC title

• C23C14/025

  Metallic sublayers · CPC title

• C23C14/0605

  Carbon · CPC title

• C23C14/35

  by application of a magnetic field, e.g. magnetron sputtering {(C23C14/3457 takes precedence)} · CPC title

• H01M8/0206

  Metals or alloys · CPC title