Perfluoropolyether-Alkoxy-Perfluoroalkane Mixture for Battery Cooling

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current heat transfer liquids for batteries and electrical components in electric vehicles face inefficiencies in cooling and longevity due to low heat capacity, high viscosity, and hygroscopicity, as well as the need for separate conduits which decrease cooling efficiency.

Innovation Solution

A liquid heat transfer mixture comprising a mixture of liquid perfluoropolyether and liquid alkoxy-perfluoroalkane, with a volume ratio of 20:80 to 80:20, providing improved electrical insulation, low evaporation, high boiling point, and increased heat capacity, allowing direct contact with electrical components for efficient cooling and heating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If dielectric oil is used for cooling batteries, then electrical insulation is provided, but heat capacity is low and cooling efficiency is limited

Engineering Contradiction:
Improveelectrical insulationVSAvoidheat capacity
Core Design Contradiction:
ReliabilityVSQuantity of substance

Solution Approach 1:

The patent uses a composite heat transfer fluid comprising perfluoropolyether and alkoxy-perfluoroalkane components. This composite formulation combines the electrical insulation properties of perfluorinated compounds with enhanced heat capacity, resolving the contradiction between insulation reliability and heat transfer quantity.

Inventive Principle:
Principle #40Composite materials

2Productivity

If liquid coolant in conduit is used, then cooling efficiency is improved, but separate conduit is required which decreases heat flow

Engineering Contradiction:
Improvecooling efficiencyVSAvoidconduit structure
Core Design Contradiction:
ProductivityVSDevice complexity

Solution Approach 1:

The patent merges the coolant function with direct contact with battery cells by using a battery cooling system where the heat transfer fluid directly contacts the battery cells through cooling plates, eliminating the need for separate conduits and maximizing heat flow while maintaining high cooling efficiency.

Inventive Principle:
Principle #5Merging (Combining)

3Reliability

If perfluoropolyether is used, then electrical insulation and high boiling point are achieved, but viscosity is high and heat capacity is low

Engineering Contradiction:
Improveelectrical insulationVSAvoidviscosity
Core Design Contradiction:
ReliabilityVSSpeed

Solution Approach 1:

The patent changes the physical and chemical parameters of the heat transfer fluid by formulating a mixture of perfluoropolyether and alkoxy-perfluoroalkane in specific ratios. This parameter optimization reduces viscosity while maintaining electrical insulation properties and enhances heat capacity through the synergistic combination of components.

Inventive Principle:
Principle #35Parameter changes

4Quantity of substance

If alkoxy-perfluoroalkane is used, then heat capacity is increased, but electrical insulation properties deteriorate and hygroscopicity increases

Engineering Contradiction:
Improveheat capacityVSAvoidelectrical insulation
Core Design Contradiction:
Quantity of substanceVSReliability

Solution Approach 1:

The patent formulates a composite heat transfer fluid where perfluoropolyether and alkoxy-perfluoroalkane are combined in specific proportions. The perfluoropolyether component provides electrical insulation and high boiling point, while the alkoxy-perfluoroalkane contributes enhanced heat capacity, creating a synergistic mixture that balances all required properties.

Inventive Principle:
Principle #40Composite materials

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 mixture offers enhanced electrical insulation, reduced evaporation, and improved heat transfer capabilities, extending the usable life to two to three years while maintaining high cooling efficiency, outperforming individual components in terms of heat capacity and longevity.

Implementation Method 1

a liquid heat transfer mixture comprising a mixture of a liquid perfluoropolyether and a liquid alkoxy-perfluoroalkane... for cooling or heating batteries and other electrical components

Methodology Applied
Scientific EffectHeat transfer: Conduction (thermal)

Implementation Method 2

passing a coolant fluid through a conduit arranged in the battery along the battery cells

Methodology Applied
Scientific EffectConvection: Convection

Implementation Method 3

cooling the batteries during charging, prior to use, and during discharging as the electric vehicle is used

Methodology Applied
Scientific EffectHeat absorption: Absorption (physical)

Implementation Method 4

providing improved electrical insulation... outperforming individual components in terms of heat capacity and longevity

Methodology Applied
Scientific EffectElectrical insulation: Dielectric

Data Source

PatentEP3757190B1Liquid heat transfer mixture and use thereof
Publication Date: 2021.10.13 SADAIR SPEAR

AI summary

A liquid heat transfer mixture comprises a mixture of a liquid perfluoropolyether and a liquid alkoxy-perfluoroalkane, wherein the volume ratio of the liquid perfluoropolyether to the liquid alkoxy-perfluoroalkane is from 20:80 to 80:20. Use of the liquid heat transfer mixture is also disclosed.