Redox Flow Battery Electrolyte Impurity Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Redox flow batteries face issues with precipitate generation and hydrogen production during battery reactions, leading to decreased performance and energy density, due to unidentified impurity ions in the electrolyte.

Innovation Solution

The electrolyte for redox flow batteries is formulated with a total concentration of impurity element ions below 220 mass ppm and platinum-group element ions below 4.5 mass ppm, specifically adjusting concentrations of metal, non-metal, and platinum-group element ions to suppress precipitate and hydrogen generation, thereby enhancing battery performance and energy density.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the concentration of impurity element ions in the electrolyte is not controlled, then the battery can operate with simpler electrolyte preparation, but precipitate is generated during battery reactions causing performance degradation

Engineering Contradiction:
Improvebattery performance stabilityVSAvoidelectrolyte preparation complexity
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The patent specifies precise concentration parameters for impurity element ions (total concentration of 220 mass ppm or less and platinum-group element ions of 4.5 mass ppm or less) to prevent precipitate formation during battery reactions, thereby maintaining reliable battery performance while providing clear manufacturing guidelines

Inventive Principle:
Principle #35Parameter changes

2Quantity of substance

If the electrolyte contains higher concentrations of active materials to increase energy density, then the battery capacity increases, but precipitate generation is accelerated causing performance degradation

Engineering Contradiction:
Improveenergy densityVSAvoidbattery performance stability
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent establishes specific concentration thresholds for impurity element ions (220 mass ppm or less total, 4.5 mass ppm or less for platinum-group) that enable high energy density operation while preventing the accelerated precipitate formation that would otherwise occur at higher active material concentrations

Inventive Principle:
Principle #35Parameter changes

3Productivity

If charging is maximized to increase utilization, then the battery capacity is optimized, but hydrogen generation occurs through water decomposition side reactions

Engineering Contradiction:
Improvebattery utilizationVSAvoidhydrogen generation
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent controls the concentration of platinum-group element ions at 4.5 mass ppm or less, which suppresses catalytic activity for water decomposition, thereby enabling maximized charging and utilization without significant hydrogen generation from side reactions

Inventive Principle:
Principle #35Parameter changes

4Reliability

If the electrolyte is purified to remove all impurities, then precipitate and hydrogen generation are suppressed, but the manufacturing cost and complexity increase significantly

Engineering Contradiction:
Improveprecipitate suppressionVSAvoidelectrolyte purification process
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent defines practical concentration thresholds (220 mass ppm or less for total impurity element ions, 4.5 mass ppm or less for platinum-group element ions) that provide effective precipitate suppression while establishing achievable purification targets that balance performance with manufacturing feasibility

Inventive Principle:
Principle #35Parameter changes

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 formulation effectively reduces precipitate formation and hydrogen production, leading to improved battery performance and increased energy density by optimizing the concentrations of impurity and platinum-group element ions in the electrolyte.

Implementation Method 1

a total concentration of impurity element ions contributing to generation of precipitate during a battery reaction is 220 mass ppm or less

Methodology Applied
Scientific EffectPrecipitation: Precipitation

Implementation Method 2

a total concentration of platinum-group element ions is 4.5 mass ppm or less

Methodology Applied
Scientific EffectElectrolysis: Electrolysis

Data Source

PatentEP2876717B1Redox flow battery including an electrolyte and the use of an electroylte in a redox flow battery
Publication Date: 2016.11.09 SUMITOMO ELECTRIC INDUSTRIES LTD
  • EP2876717B1 patent drawingFigure 1

AI summary

Provided are an electrolyte for a redox flow battery, the electrolyte allowing suppression of generation of precipitate and suppression of generation of hydrogen during a battery reaction; and a redox flow battery including the electrolyte. In the electrolyte for a redox flow battery, the total concentration of impurity element ions contributing to generation of precipitate during a battery reaction is 220 mass ppm or less, and the total concentration of platinum-group element ions is 4.5 mass ppm or less. In a case where the impurity element ions contributing to generation of precipitate include metal element ions, the total concentration of the metal element ions may be 195 mass ppm or less.