A proton exchange membrane fuel cell stack steel belt fastening device

Abstract

The invention discloses a proton exchange membrane fuel cell stack steel strip fastening device. Its structure includes, from back to front, a rear end plate, a rear end copper bar, a graphite plate membrane electrode group, a front end copper bar, a front end plate, and a dish. Spring and disc spring pressure plate, and then use U-shaped steel belt to lock the above parts. A certain arc surface is designed on the rear end plate. In order to allow the steel belt to apply the binding force to the graphite plate membrane electrode group more evenly, in A groove is made at the joint of the steel strip on the rear end plate to facilitate the clamping of the steel strip; a slot is made on the front end plate so that the disc spring pressure plate can be inserted, in order to allow the first bolt to be screwed into the crossbar. Prevent the steel belt from twisting and the steel belt will not touch the graphite plate. When the length of the graphite plate membrane electrode group becomes shorter, the disc spring is loosened by a certain length to offset the change in the length of the graphite plate membrane electrode group; when the length of the graphite plate membrane electrode group becomes longer, the disc spring is compressed to offset the length change of the graphite plate membrane electrode group. The change in the length of the group ensures that the performance of the stack will not be affected too much.

Description

technical field [0001] The invention relates to the field of proton exchange fuel cells, in particular to a proton exchange membrane fuel cell stack steel belt fastening device. Background technique [0002] A fuel cell is a device that directly converts the chemical energy of an oxidizing agent and a reducing agent into electrical energy through an electrocatalytic reaction. It is a new type of power generation device that is efficient, safe, clean and flexible. Among them, the proton exchange membrane fuel cell has a wide range of application prospects in ground power stations, electric vehicles and portable power supplies due to its significant advantages such as high efficiency, high energy density, low reaction temperature, no noise, and no pollution. The interior of the fuel cell is mainly composed of proton exchange membrane, electrochemical reaction catalyst, diffusion layer and bipolar plate. When the fuel cell is working, the following reaction process occurs insi...

AI Technical Summary

Problems solved by technology

[0009] 1. Use a stainless steel strip with a thickness of 0.1-0.5cm. The steel strip must be bent into that shape before use. Once bent, the length of the straight line in the middle of the steel strip will be fixed, but the "graphite" in the middle of the fuel cell The ideal compression length of the "plate and membrane electrode" cannot be accurately known in advance and needs to be adjusted during the activation test. Therefore, once the steel strip in this patent is installed, it cannot be fine-tuned, and the performance of the stack cannot be well controlled.

[0010] 2. As the temperature changes, thermal expansion and contraction occur, the elasticity of the membrane electrode decreases, and the sealant on the surface of the graphite plate deforms, resulting in a change in the length of the "graphite plate and membrane electrode" in the middle of the fuel cell. However, this steel strip structure cannot Adapting to this length change will have a certain performance impact on the fuel cell

[0012] 1. After the battery is assembled by the assembly equipment, after the battery is removed from the assembly equipment, it needs to use a large rotational force to tighten it further. The wrench is limited by the side of the battery, and the rotation can only be within a certain angle.

[0013] 2. During the fastening process, the steel strip will be twisted and hit the graphite plate

Images