Flow Battery Electrolyte Composition for Low Hydrogen Gas Generation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Flow battery systems generate excessive gases such as hydrogen and hydrogen sulfide due to side reactions, which is undesirable and affects battery efficiency and performance.
Innovation Solution
An electrolyte for flow batteries with controlled concentrations of specific impurity element ions, such as those from groups 1 to 8 and 13 to 16 in the periodic table, is developed, keeping their total concentration at 610 mg/L or less, along with vanadium ions, sulfuric acid, phosphoric acid, ammonium, and silicon within specific ranges, to minimize gas generation during charging and discharging.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Object-generated harmful factors
If conventional electrolytes with higher impurity ion concentrations are used, then battery reaction efficiency is maintained, but gas generation increases
Solution Approach 1:
The patent applies parameter changes by precisely controlling the concentration of impurity element ions in the electrolyte. Specifically, it limits the total concentration of ions from groups 1-8 and 13-16 (5th period) and groups 1, 2, and 4-8 (6th period) to 610 mg/L or less, while maintaining vanadium ion concentration at 1-3 mol/L and free sulfuric acid at 1-4 mol/L. This parameter optimization reduces gas generation while preserving battery reaction efficiency.
2Object-generated harmful factors
If impurity element ion concentration is reduced, then gas generation decreases, but manufacturing complexity increases
Solution Approach 1:
The patent applies preliminary action by pre-controlling the concentration of impurity element ions during electrolyte preparation. The electrolyte is formulated with vanadium ions, free sulfuric acid, phosphoric acid, and controlled impurity ions (total ≤610 mg/L) before being supplied to the flow battery. This advance preparation ensures low gas generation without requiring complex in-situ adjustments during battery operation.
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
The electrolyte effectively reduces gas generation in the negative electrode, maintaining good battery characteristics and preventing precipitation of active material compounds, thus enhancing the performance and efficiency of the flow battery system.
Implementation Method 1
containing, as an active material, ions whose valence is changed by oxidation-reduction
Implementation Method 2
a generation rate of hydrogen is less than 10 cc/h/m2 and a generation rate of hydrogen sulfide is less than 5.0×10−3 cc/h/m2, the hydrogen and the hydrogen sulfide being generated in a negative electrode of the flow battery during charging and discharging
Data Source
AI summary
Provided is an electrolyte for a flow battery, the electrolyte being supplied to a flow battery, in which a total concentration of ions of elements of groups 1 to 8 and ions of elements of groups 13 to 16 in the fifth period of the periodic table, and ions of elements of groups 1, 2, and 4 to 8 and ions of elements of groups 13 to 15 in the sixth period of the periodic table, the ions being impurity element ions involved in generation of a gas containing elemental hydrogen, may be 610 mg/L or less and a concentration of vanadium ions may be 1 mol/L or more and 3 mol/L or less.