Double-Cover Battery Pack Venting for Flame and Particle Blocking

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing battery packs fail to effectively vent gases and prevent leakage of flames or high temperature particles during a fire, leading to thermal damage and fire spread to adjacent modules.

Innovation Solution

A battery pack design featuring a top plate portion with a flame-retardant pad layer, a flame barrier mesh layer, and a vent slit, which allows gases to be vented outdoors while blocking flames and high temperature particles, using a double cover structure with a pack tray and cover.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a single cover structure is used, then the device complexity is low, but gases cannot be effectively vented and flames/high temperature particles leak during fire

Engineering Contradiction:
Improvefire safetyVSAvoidcover structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The cover is divided into an upper cover and a lower cover, forming a double cover structure. The lower cover includes a vent passage with a vent hole, while the upper cover has a flame arrester with mesh structure. This segmentation allows gases to vent through the lower cover while the upper cover's flame arrester blocks flames and high temperature particles, resolving the contradiction between simple structure and fire safety.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

A flame arrester is introduced as an intermediary component between the vent passage and the external environment. The flame arrester includes a mesh structure that allows gases to pass through while blocking flames and high temperature particles. This intermediary element enables the system to achieve both effective gas venting and fire prevention simultaneously.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Object-generated harmful factors

If venting holes are provided in the cover, then gases can be vented, but flames and high temperature particles leak causing thermal damage to adjacent modules

Engineering Contradiction:
Improvegas pressureVSAvoidthermal damage
Core Design Contradiction:
Object-generated harmful factorsVSObject-affected harmful factors

Solution Approach 1:

The flame arrester acts as an intermediary component that allows gas passage while blocking harmful thermal elements. The mesh structure of the flame arrester permits gases to escape from the pressurized battery module while intercepting flames and high temperature particles, preventing thermal damage to adjacent modules.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The flame arrester is positioned specifically at the vent passage opening, creating a localized safety zone. The mesh structure provides different functional qualities: it is permeable to gases while being impermeable to flames and particles. This local quality differentiation resolves the contradiction between gas venting and thermal protection.

Inventive Principle:
Principle #3Local quality

3Object-affected harmful factors

If a flame arrester with mesh structure is added, then flames and particles are blocked, but the device complexity increases

Engineering Contradiction:
Improveflame leakageVSAvoidcover components
Core Design Contradiction:
Object-affected harmful factorsVSDevice complexity

Solution Approach 1:

The cover system is segmented into functional components: the lower cover with vent passage for gas escape, and the upper cover with flame arrester for thermal protection. This segmentation distributes the safety functions across separate components, making the overall system more manageable and maintainable despite the increased complexity.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The flame arrester utilizes a composite structure combining a support frame with a mesh layer. The mesh structure can be made of flame-retardant materials that provide both structural integrity and thermal blocking capability. This composite approach achieves effective flame and particle blocking while keeping the component design integrated and manageable.

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

Effectively vents gases to prevent flame and particle leakage, minimizing thermal damage and delaying fire spread to adjacent modules, enhancing durability and reducing maintenance costs.

Implementation Method 1

a flame barrier mesh layer (330) between the upper and lower plates (310, 320) to prevent leakage of flames or high temperature particles

Methodology Applied
Scientific EffectPhysical barrier (mesh structure): Filter (physical)

Implementation Method 2

the vent slit is configured to be torn when higher pressure than an allowable pressure is applied

Methodology Applied
Scientific EffectPressure-induced fracture: Fracture Mechanics

Data Source

PatentEP4391184B1Battery pack having double top cover with venting gas passage
Publication Date: 2025.11.05 LG ENERGY SOLUTION LTD
  • EP4391184B1 patent drawingFigure 1
  • EP4391184B1 patent drawingFigure 2
  • EP4391184B1 patent drawingFigure 3

AI summary

A battery pack according to the present disclosure includes a pack tray accommodating at least one battery module; a pack cover covering a top of the pack tray, and having a vent passage of venting gas; and a top plate portion disposed between the pack tray and the pack cover and having a lower part facing the battery module and an upper part communicating with the vent passage, wherein the top plate portion is configured to selectively vent the venting gas among flame, high temperature particle and the venting gas generated from the battery module.