What are the advantages of all vanadium redox flow battery energy storage technology?

The all vanadium redox flow battery stores the vanadium ion solutions of different valence states as the active substances of the positive and negative electrodes respectively in the electrolyte storage tank. The electrolyte stored in the tank is pumped into the stack to make it circulate in the closed circuits of different liquid storage tanks and half cells. The ion conduction membrane is used as the battery diaphragm. The electrolyte flows through the electrode surface in parallel and produces electrochemical reaction, and the current is collected and conducted through the bipolar plate, Realize the conversion of electrolyte chemical energy and electric energy.

All vanadium flow battery is a fixed high-capacity energy storage system suitable for power system. Compared with other energy storage technologies, vanadium battery energy storage technology has the following main characteristics:

1. High safety. The energy storage active material of the battery is dilute sulfuric acid aqueous solution containing vanadium ion. It operates at room temperature and pressure. After long-term operation, even if the positive and negative active materials are mixed with each other, there will be no explosion and combustion. During operation, the electrolyte circulates between the stack and the electrolyte storage tank, the heat generated by the stack can be effectively discharged, and the heat management is simple. Good consistency between single cells. So far, none of the systems installed in the world have been on fire.

2. Long cycle life, good battery uniformity and deep discharge. Because the electric energy is stored in the electrolyte instead of on the electrode, it can be charged and discharged infinitely in theory. The capacity decline after a certain period of operation can be recovered online or offline.

3. The cost performance of the life cycle is high, and the electrolyte accounting for about 30% ~ 50% of the whole cost (depending on the length of energy storage) can be recycled.

5. Good charge and discharge characteristics, fast response speed, energy efficiency of 80%, deep discharge. In addition, vanadium ion has high electrochemical reversibility and small electrochemical polarization, which is suitable for high current rapid charge and discharge. The charge and discharge switching takes only 0.02 seconds.

6. The power and capacity can be designed independently. The power and capacity are determined by the number of stacks and electrolyte respectively, which makes the design more flexible. The energy storage capacity is hundreds of kW to hundreds of MW, and the output power is hundreds of kW to hundreds of MW, which is especially suitable for large-scale energy storage.

7. The life cycle is environment-friendly, the electrolyte can be recycled and recycled, vanadium resources and other materials are abundant, the processing technology is mature and easy to recycle. This technology is an important direction of comprehensive utilization of vanadium resources.