Redox Flow Battery System for Distributed Energy Storage

Abstract

A large stack redox flow battery system provides a solution to the energy storage challenge of many types of renewable energy systems. Independent reaction cells arranged in a cascade configuration are configured according to state of charge conditions expected in each cell. The large stack redox flow battery system can support multi-megawatt implementations suitable for use with power grid applications. Thermal integration with energy generating systems, such as fuel cell, wind and solar systems, further maximize total energy efficiency. The redox flow battery system can also be scaled down to smaller applications, such as a gravity feed system suitable for small and remote site applications.

1 - 8 . (canceled) 
     
     
         9 . A flow battery energy storage system, comprising:
 a reactant flow path having a first end and a second end; and   a plurality of flow battery cells arranged along the reactant flow path, wherein:
 an outlet of a first one of the plurality of flow battery cells is coupled to an inlet of a second one of the plurality of flow battery cells, 
 the first one of the plurality of flow battery cells comprises a first at least one of: a structural configuration and a material configuration, according to a first position along the reactant flow path, 
 the second one of the plurality of flow battery cells comprises a second at least one of: a structural configuration and a material configuration, according to a second position of the second one of the plurality of flow battery cells along the reactant flow path, and 
 the first at least one of: the structural configuration and the material configuration, and the second at least one of: the structural configuration and the material configuration are different based on the first position and the second position along the reactant flow path. 
   
     
     
         10 . The flow battery energy storage system of claim  1 , wherein the first at least one of: the structural configuration and the material configuration, and the second at least one of: the structural configuration and the material configuration each comprise a flow directing structure that causes mixing of electrolytes entering the first one of the plurality of flow battery cells and the second one of the plurality of flow battery cells to increase a total energy efficiency of the flow battery energy storage system. 
     
     
         11 . The flow battery energy storage system of claim  1 , wherein the first at least one of: the structural configuration and the material configuration and the second at least one of: the structural configuration and the material configuration each comprise a heating structure to heat a reactant in the reactant flow path and thereby increase a total energy efficiency of the flow battery energy storage system. 
     
     
         12 . The flow battery energy storage system of claim  1 , wherein the first at least one of: the structural configuration and the material configuration and the second at least one of: the structural configuration and the material configuration each comprise a first electrode having a configuration according to the first position and the second position to increase a total energy efficiency of the flow battery energy storage system. 
     
     
         13 . The flow battery energy storage system of claim  4 , wherein the first electrode has a surface area configuration according to the first position and the second position that increases the total energy efficiency of the flow battery energy storage system. 
     
     
         14 . The flow battery energy storage system of claim  4 , wherein the first at least one of: the structural configuration and the material configuration, and the second at least one of: the structural configuration and the material configuration each comprise a catalyst loading of a catalyst on the first electrode, the catalyst loading configured to increase the total energy efficiency of the flow battery energy storage system. 
     
     
         15 . The flow battery energy storage system of claim  1 , wherein the first at least one of: the structural configuration and the material configuration, and the second at least one of: the structural configuration and the material configuration each comprise a separator membrane having at least a material configuration according to the first position and the second position that increases a total energy efficiency of the flow battery energy storage system. 
     
     
         16 . The flow battery energy storage system of claim  7 , wherein the at least the material configuration of the separator membrane comprises a selectivity according to the first position and the second position that increases the total energy efficiency of the flow battery energy storage system. 
     
     
         17 . The flow battery energy storage system of claim  1  wherein the first least one of: the structural configuration and the material configuration, and the second at least one of: the structural configuration and the material configuration each comprise an electrode chamber having a dimensional size that allows a mass transport rate of reactant through the respective first one of the plurality of flow battery cells and the second one of plurality of flow battery cells that increases a total energy efficiency of the flow battery energy storage system. 
     
     
         18 . The flow battery energy storage system of claim  1 , wherein the plurality of flow battery cells comprises a first plurality of flow battery cell arrays arranged along the reactant flow path in a cascade flow orientation relative to a second plurality of flow battery cell arrays. 
     
     
         19 . A flow battery energy storage system, comprising:
 a reactant flow path having a first end and a second end; and   a plurality of flow battery cells arranged along the reactant flow path, wherein:
 an outlet of a first one of the plurality of flow battery cells is coupled to an inlet of a second one of the plurality of flow battery cells, 
 the first one of the plurality of flow battery cells comprises a first at least one of: a structural configuration and a material configuration, according to a first electrolyte state-of-charge at a first position along the reactant flow path, 
 the second one of the plurality of flow battery cells comprises a second at least one of: a structural configuration and a material configuration, according to a second electrolyte state-of-charge at a second position of the second one of the plurality of flow battery cells along the reactant flow path, and 
 the first at least one of the structural configuration; and the material configuration, and the second at least one of: the structural configuration and the material configuration are different based on the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
   
     
     
         20 . The flow battery energy storage system of  claim 11 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: the structural configuration and the material configuration each comprise a flow directing structure that causes mixing of electrolytes entering the first one of the plurality of flow battery cells to increase total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         21 . The flow battery energy storage system of  claim 11 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: a structural configuration and a material configuration each comprise a catalyst coated onto an electrode in each of the first flow battery cell and the second flow battery cell, the catalyst configured to increase a total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         22 . The flow battery energy storage system of  claim 13 , wherein the catalyst is configured with a catalyst loading selected to increase the total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         23 . The flow battery energy storage system of  claim 13 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: a structural configuration and a material configuration each comprise a catalyst activity of the first electrode-that is configured to increase the total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         24 . The flow battery energy storage system of  claim 11 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: a structural configuration and a material configuration each comprise a first electrode configured to increase a total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         25 . The flow battery energy storage system of  claim 16 , wherein the first electrode is configured with a surface area configuration that increases the total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         26 . The flow battery energy storage system of  claim 11 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: a structural configuration and a material configuration each comprise a heating structure to heat reactant and thereby increase a total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         27 . The flow battery energy storage system of  claim 11 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: a structural configuration and a material configuration each comprise an electrode porosity selected corresponding to a transport rate that increases a total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         28 . The flow battery energy storage system of  claim 11 , wherein the first at least one of: the structural configuration; and the material configuration, and the second at least one of: a structural configuration and a material configuration each comprise a separator membrane that increases a total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge. 
     
     
         29 . The flow battery energy storage system of  claim 20 , wherein the separator membrane has a selectivity that increases the total energy efficiency at the first electrolyte state-of-charge and the second electrolyte state-of-charge.