Vanadium Redox Flow Batteries(VRFB) are one of the most sustainable solutions for stationary energy storage. They provide a long operational lifetime, negligible degradation and self-discharge, and low levelized cost of storage(LCOS).
In addition, the batteries are simple to recycle even after 20 years of use. The combination of sustainability and low lifetime costs makes VRFBs perfect for long duration (4+ hours) stationary energy storage.
Instead of the energy being stored in solid materials the energy is stored in liquid electrolyte which is pumped through a battery cell. This reduces the energy density compared to some other battery technologies, meaning that you wont see VRFBs in mobile units such as cellphones or electric cars. However, in stationary applications where the energy denisity is not as crucial it provides great benefits.
The capacity of VRFBs does not fade away by charging or discharging the system. This results in practically unlimited cycles over 20 years of use.
Since the electrolyte does not degrade by being used its easy to upcycle, resycle or in some cases imidatly reuse it in new systems.
Most of the system weight consits of liquid non-flammable materials, making the system robust against fire - even external flames.
VRFBs lifespan is 2-4 times longer than most competing technologies. In addition, no capacity fade reduces to the cost of services and mainainance. This combination gives VRFBs one of the lowest lifetime costs (LCOS).
The power and capacity components of the system are completely independant from each other. If you need more power, you install more battery stacks, if you need more capacity, you install bigger tanks with elecotrlyte. The overall system cost per kwh is lower the more capacity is included. Therefore most flow batteries are designed for 4, 8, 12 hours or more.
VRFBs have practically no self-discharge, enabling new opportunities for long-duration or even seasonal energy storage.