Electrode frame and all-vanadium redox flow battery pile

Abstract

The invention relates to a novel electrode frame for an all-vanadium redox flow battery pile, which improves the utilization rate of membrane materials compared with the traditional battery pile and can not need perforation. The improvement of the utilization rate of the membrane materials leads the cost of the battery pile to be lowered, the membrane materials lead the assembly difficulty of the battery pile to be reduced without perforation, and the stability of the battery pile is improved after the battery pile is operated for a long time, thereby ensuring the further engineering magnification and the assembly of the battery pile with larger power.

Description

technical field [0001] The invention relates to an all-vanadium flow energy storage battery, in particular to an electrode frame and an all-vanadium flow energy storage battery stack. Background technique [0002] The world-wide energy shortage and the aggravated deterioration of the environment have prompted the calls of countries all over the world to develop and utilize renewable energy. However, no matter solar or wind energy, there is instability in energy supply, and an energy storage system with excellent performance is required to match it. Scale energy storage technology is also required for peak shaving and valley filling and load balancing of the power grid. [0003] Liquid flow batteries have long life, high reliability, flexible design, no special terrain requirements, low operation and maintenance costs, and are ideal large-scale energy storage devices. Compared with other types of flow batteries, all-vanadium flow batteries have unique advantages: (1) The po...

AI Technical Summary

Problems solved by technology

Bipolar plates, electrode frames, and sealing materials have good dimensional stability, but the ion-exchange membranes currently used in all-vanadium redox flow batteries, such as Nafion, Flemion, Selemion CMV, and CMS, have different degrees of swelling properties, and their dimensions Poor stability, different water content, large size change

This leads to difficulties in positioning the holes during stack assembly

Even if the precise positioning can be achieved during assembly, the size of the ion exchange membrane will change due to the change of water content during the operation of the battery, so that the ion exchange membrane will be deformed, and the electrolyte channel may be partially blocked, so that the battery stack electrolyte supply Insufficient concentration polarization is likely to occur inside the battery stack, resulting in a decrease in charge and discharge capacity

Partial blockage of the electrolyte channel may also cause uneven distribution of the electrolyte, resulting in excessive local voltage of the battery stack, causing oxidation and corrosion of the plate and electrode materials, thus affecting the long-term operation stability and life of the battery

At the same time, it will also increase the flow resistance of the electrolyte, increase the pump consumption, and reduce the energy efficiency of charging and discharging of the entire system.

[0005] In addition, the external dimensions of the ion exchange membrane used in the current battery stack are the same as the external dimensions of the electrode frame, and the membrane that can play the role of ion transfer is only the part that is in contact with the electrode, and the membrane that is in contact with the electrode frame cannot achieve ion conduction. role, which undoubtedly causes a waste of membrane materials and increases the cost of the battery stack

[0006] The existence of the above problems not only increases the difficulty of battery stack assembly, but also increases the cost of the battery stack, especially when the battery stack is further enlarged, the severity of these problems will become more prominent

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