Flexible phase change material composite for thermal management systems

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Phase change material (PCM) composites used in thermal management systems for lithium-ion batteries face limitations due to the graphite matrix's low mechanical strength, brittleness, inflexibility, and non-compressibility, which can lead to mechanical stress and electrical short-circuits.

Innovation Solution

A thermal management composite is developed by incorporating a carbon or graphite matrix with a phase change material and a polymer material, where the polymer is dispersed within or coated onto the matrix, enhancing mechanical properties and electrical resistivity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Temperature

If graphite matrix is used in PCM composite, then thermal conductivity is improved, but mechanical strength and flexibility deteriorate

Engineering Contradiction:

Improvethermal conductivityVSAvoidmechanical strength

Core Design Contradiction:

TemperatureVSStrength

Solution Approach 1:

The patent uses a composite structure combining graphite particles (for thermal conductivity) with a polymer matrix (for mechanical strength and flexibility). The graphite particles are dispersed throughout the polymer matrix, creating a composite material that exhibits both high thermal conductivity and improved mechanical properties compared to pure graphite or pure polymer.

Inventive Principle:

Principle #40Composite materials

2Temperature

If graphite matrix is used in PCM composite, then thermal management performance is improved, but electrical resistivity deteriorates

Engineering Contradiction:

Improvethermal management performanceVSAvoidelectrical short-circuit risk

Core Design Contradiction:

TemperatureVSObject-affected harmful factors

Solution Approach 1:

The patent applies local quality by using graphite particles specifically for thermal conduction pathways while the polymer matrix provides electrical insulation. The graphite is distributed locally throughout the material to create thermal conduction networks, while the surrounding polymer ensures electrical resistivity and prevents short circuits between battery cells.

Inventive Principle:

Principle #3Local quality

3Temperature

If graphite matrix is used in PCM composite, then thermal contact with cells is improved, but compressibility and flexibility deteriorate

Engineering Contradiction:

Improvethermal contactVSAvoidcompressibility

Core Design Contradiction:

TemperatureVSAdaptability or versatility

Solution Approach 1:

The patent changes the physical parameters of the matrix material from rigid graphite to flexible polymer, which fundamentally alters the mechanical properties. The polymer matrix can be formulated with appropriate viscosity and elasticity to provide both good thermal contact with battery cells and the necessary compressibility to accommodate cell expansion during charging cycles.

Inventive Principle:

Principle #35Parameter changes

4Strength

If polymer material is added to graphite matrix, then mechanical strength and flexibility are improved, but thermal conductivity may deteriorate

Engineering Contradiction:

Improvemechanical strengthVSAvoidthermal conductivity

Core Design Contradiction:

StrengthVSTemperature

Solution Approach 1:

The patent utilizes a porous structure where graphite particles are embedded in the polymer matrix. The porous arrangement allows for optimized thermal pathways through the graphite particles while maintaining the mechanical properties provided by the polymer. The void spaces and particle distribution create efficient thermal conduction networks without compromising the flexibility and strength of the overall composite.

Inventive Principle:

Principle #31Porous 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 composite achieves improved flexibility, compressibility, and mechanical strength, preventing breakage under stress while maintaining thermal contact, and reducing the risk of electrical shorts, suitable for high-power applications like Li-ion pouch cells.

Implementation Method 1

The PCM absorbs large amount of heat close to its phase transition temperature thereby stabilizing and controlling battery temperature to safe operating limits

Methodology Applied

Scientific EffectPhase change: Phase Change

Implementation Method 2

The PCM absorbs large amount of heat close to its phase transition temperature

Methodology Applied

Scientific EffectLatent heat: Latent Heat

Implementation Method 3

The heat released by Li-ion cells is conducted away by the graphite matrix to the PCM

Methodology Applied

Scientific EffectThermal conduction: Conduction (thermal)

Data Source

PatentUS10597569B2Flexible phase change material composite for thermal management systems

Publication Date: 2020.03.24 BEAM GLOBAL INC

AI summary

A thermal management composite, comprising a phase change material within a carbon or graphite matrix. The matrix is coated with a polymer coating to improve flexibility. The matrix can be a molded carbon or graphite material or a carbon or graphite cloth.