Flow Battery Standby Mode for Rapid Power Response
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Prior flow battery systems are slow to react when switching between ON and OFF modes, resulting in delayed access to energy capacity and reduced rate of electric power output due to the need to circulate liquid anolyte and catholyte through the electrochemical cell.
Innovation Solution
The introduction of a STANDBY mode, controlled by a software or hardware controller, allows for instant or near-instant access to a portion of the flow battery system's capacity by storing liquid anolyte and catholyte within the electrochemical cell, reducing the need for circulation and minimizing self-discharge.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If liquid anolyte and catholyte are circulated through the electrochemical cell to access energy capacity, then the system can charge and discharge, but the response time is delayed and the rate of electric power output is reduced
Solution Approach 1:
The system pre-fills a standby electrochemical cell with liquid anolyte and catholyte before operation is needed. This preliminary action ensures that when power demand arises, the cell is immediately ready to generate electricity without waiting for electrolyte circulation, thus improving both response speed and power output rate
2Quantity of substance
If liquid anolyte and catholyte are stored in external tanks and circulated into the electrochemical cell, then energy capacity is available, but the system takes time to react and access capacity
Solution Approach 1:
The standby cell is pre-filled with the required quantity of liquid anolyte and catholyte in advance. This eliminates the time delay associated with circulating electrolytes from external tanks during operation, while maintaining full energy capacity availability for immediate use
3Loss of energy
If the system operates in OFF mode to prevent self-discharge, then energy is preserved, but the system is slow to react when power is needed
Solution Approach 1:
The system divides the electrochemical storage into two separate cells: an active cell that can respond immediately to power demands, and a standby cell that remains pre-filled but inactive. This segmentation allows the active cell to operate without self-discharge concerns while the standby cell provides immediate response capability when needed
Solution Approach 2:
The standby cell is prepared in advance with electrolytes already in place, so when power is needed, it can immediately begin operation without the delay of circulating electrolytes, thus improving reaction speed while maintaining energy preservation
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
Enables rapid response to power demands, reducing the time required to fully charge or discharge the system and increasing the rate of electric power output, while maintaining energy capacity availability without circulating electrolytes.
Implementation Method 1
A basic flow battery includes a redox flow cell that has a negative electrode and a positive electrode separated by an electrolyte layer... A negative liquid electrolyte is circulated through the negative electrode and a positive liquid electrolyte is circulated through the positive electrode to drive electrochemically reversible redox reactions.
Implementation Method 2
The separator prevents the electrolytes from mixing but permits selected ions to pass through to complete the redox reactions.
Data Source
Figure 1A~2
Figure 1B~3
Figure 4
AI summary
A flow battery system includes an ON mode, and OFF mode and a STANDBY mode. The ON mode enables access to a full energy capacity of the flow battery system with regard to an amount of electric power that can be drawn from or stored to the flow battery system. The OFF mode disables access to the full energy capacity and the STANDBY mode enables access to a portion of the full energy capacity.