Redox Flow Battery String State of Charge Matching
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current large-scale redox flow battery systems face challenges in maintaining consistent performance across multiple batteries in a string due to manufacturing variations and stack differences, leading to performance mismatches and capacity degradation, which affects energy storage efficiency and reliability.
Innovation Solution
A method of operating a redox flow battery string involves determining the state-of-charge (SOC) values for each battery, identifying a target SOC value based on the SOC values of all batteries, and adjusting the SOC values by using stored energy to balance the electrical load, thereby matching the SOC levels and mitigating performance degradation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If multiple redox flow batteries are connected in a string, then the energy storage capacity increases, but performance mismatches and capacity degradation occur due to manufacturing variations and stack differences
Solution Approach 1:
The patent applies parameter changes by dynamically adjusting the state of charge (SOC) of individual batteries within the string. By monitoring SOC values and selectively charging or discharging specific batteries based on their individual states, the system compensates for manufacturing variations and stack differences, maintaining performance consistency across all batteries in the string.
2Duration of action of stationary object
If SOC values of batteries in a string are not matched, then capacity degradation occurs, but implementing SOC matching requires additional control complexity
Solution Approach 1:
The patent implements feedback control by continuously monitoring the SOC values of all batteries in the string and using this information to control charging and discharging operations. The system adjusts the operation of individual batteries based on real-time SOC measurements, ensuring that all batteries reach matched SOC states while extending cycle life through this intelligent control approach.
3Productivity
If individual battery SOC values differ significantly, then energy storage efficiency decreases, but measuring and monitoring each battery's SOC adds system complexity
Solution Approach 1:
The patent applies universality by using a single control system that performs multiple functions: it monitors SOC values of all batteries, determines target SOC states, controls charging and discharging operations, and adjusts individual battery operations. This multi-functional approach improves energy storage efficiency through SOC matching while avoiding the need for separate measurement and control systems for each battery.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach enhances energy density and extends the cycle life of the battery string by maintaining stable performance across all batteries, reducing capacity loss and improving overall energy storage efficiency.
Implementation Method 1
species from one half-cell lose electrons (oxidation) to their electrode
Implementation Method 2
species from the other half-cell gain electrons (reduction) from their electrode
Implementation Method 3
RFBs are special electrochemical systems that can repeatedly store and convert megawatt-hours (MWhs) of electrical energy to chemical energy and chemical energy back to electrical energy when needed
Data Source
AI summary
A method of operating a redox flow battery string including at least first and second redox flow batteries and an outside power source includes: providing a least first and second redox flow batteries in a string electrically connected in a string, and each redox flow battery having a state-or-charge (SOC); obtaining an SOC value for each redox flow battery in the string; identifying a target SOC value in the string; and adjusting the SOC value for at least one of the first and second redox flow batteries to correspond to the target SOC value.