Battery Pack Protective Sheet for Thermal Runaway Safety

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional battery packs face issues with thermal runaway, where gases and spark particles from one cell assembly can transfer to others, leading to potential explosions and heat transfer, and existing solutions like opening holes do not adequately prevent this.

Innovation Solution

A battery pack design with a cell assembly that includes a module frame with opening holes covered by a protective sheet and an upper case with an elastic member pressing the sheet against the module frame, allowing gas discharge while preventing spark particle transfer.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Object-generated harmful factors

If opening holes are formed in the cell assembly to discharge gases, then gas discharge capability is improved, but spark particles can transfer to other cell assemblies causing safety issues

Engineering Contradiction:
Improvegas discharge capabilityVSAvoidspark particle transfer
Core Design Contradiction:
Object-generated harmful factorsVSObject-affected harmful factors

Solution Approach 1:

A protective sheet is introduced as an intermediary component between the opening holes and the external environment. This sheet selectively allows gas molecules to pass through while blocking larger spark particles and flames, thus resolving the contradiction between gas discharge capability and spark particle prevention

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The protective sheet is designed with a porous structure having specific pore sizes that permit gas molecules to escape during thermal runaway while being small enough to trap spark particles and prevent their transfer to adjacent cell assemblies

Inventive Principle:
Principle #31Porous materials

2Object-affected harmful factors

If the protective sheet is made rigid to effectively block spark particles, then spark particle prevention is improved, but the sheet cannot adapt to module frame deformation during thermal runaway

Engineering Contradiction:
Improvespark particle preventionVSAvoidadaptability to deformation
Core Design Contradiction:
Object-affected harmful factorsVSAdaptability or versatility

Solution Approach 1:

The protective sheet is designed with elastic properties allowing it to dynamically deform and follow the contour changes of the module frame during thermal runaway events, while maintaining its spark particle blocking capability through its elastic recovery and continuous contact with the frame surface

Inventive Principle:
Principle #15Dynamics

3Adaptability or versatility

If the protective sheet is made elastic to follow module frame deformation, then adaptability to deformation is improved, but the sheet may not effectively block spark particles

Engineering Contradiction:
Improveadaptability to deformationVSAvoidspark particle prevention
Core Design Contradiction:
Adaptability or versatilityVSObject-affected harmful factors

Solution Approach 1:

The protective sheet utilizes composite material construction combining base fabric layers with coating materials that provide both elastic deformation capability and spark particle blocking functionality, achieving a balance between adaptability and protection effectiveness

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 design effectively suppresses heat transfer to neighboring cell assemblies during thermal runaway, enhancing safety by discharging gases and preventing spark particle transfer.

Implementation Method 1

an elastic member at the lower end that presses against an upper part of the cell assembly

Methodology Applied
Scientific EffectElasticity: Elasticity

Data Source

PatentEP4645565A1Battery pack
Publication Date: 2025.11.05 LG ENERGY SOLUTION LTD
  • EP4645565A1 patent drawingFigure 1
  • EP4645565A1 patent drawingFigure 2
  • EP4645565A1 patent drawingFigure 3

AI summary

The present invention relates to a battery pack in which a cell assembly is accommodated. The battery pack includes: a pack case in which a cell assembly is seated; and an upper case coupled to the pack case so as to cover the top portion of the cell assembly seated in the pack case, wherein the upper case includes, at the bottom thereof, an elastic member for pressing the top portion of the cell assembly seated in the pack case.