From Yahoo boardVionx has received 5 patents in VRFB- we know that others have failed in this industry but any break through in VRFB will have to incorporate some of the Vionx patents. Vanadium flow batteries offer heavy-duty energy storage and are designed for use in high-utilization applications, such as industrial-scale solar PV generation for distributed, low-emissions energy projects. Energy is stored in a non-flammable, liquid electrolyte and the batteries do not degrade with cycling like lithium-ion options and they can be scaled and located with greater flexibility than pumped hydro energy storage. Here are Vionx Patents
Systems and methods for electrolyte storage and detecting faults in flow batteries
Patent number: 10714785
Electrochemical-based purification of electrolyte solutions, and related systems and methods
Patent number: 10333164
Systems and methods for selective cell and/or stack control in a flowing electrolyte battery
Patent number: 9325021
Flowing electrolyte battery with electric potential neutralization
Patent number: 9263753
Energy storage systems and associated methods
Patent number: 9257846