Battery Module Venting Screen Structure for Fire Propagation Control

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Lithium secondary battery modules used in electric vehicles and similar applications face challenges in stability against fire and explosion, where a single cell's fire or explosion can lead to thermal runaway and propagate to adjacent cells, posing a risk of secondary explosions.

Innovation Solution

A battery module design featuring a vent unit that discharges gas externally when internal pressure exceeds a threshold, a cell frame with exposure holes, a screen member that seals and opens exposure holes by gas pressure, and a protection plate with communication holes to ensure safe gas discharge, along with a heat-resistant sheet and adhesive or perforating features to prevent gas buildup and ensure reliable venting.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If a battery module includes multiple battery cells, then the capacity and energy storage are increased, but the risk of fire propagation and thermal runaway to adjacent cells increases

Engineering Contradiction:
Improvebattery capacityVSAvoidfire propagation risk
Core Design Contradiction:
Quantity of substanceVSObject-affected harmful factors

Solution Approach 1:

The battery module is divided into independent cell compartments within the cell frame, with each cell isolated from others. The exposure holes and screen members create segmented pathways that allow gas venting from individual cells without enabling fire or thermal runaway propagation to adjacent cells, thus maintaining high capacity while reducing fire risk through spatial segmentation.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The screen member acts as an intermediary component between the exposure holes and the external environment. It selectively allows gas passage while blocking fire and thermal runaway propagation. The screen member material and structure are designed to withstand thermal and chemical conditions, providing mediation that enables safe gas discharge while preventing harmful factor transmission between cells.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Stress or pressure

If exposure holes are opened in the cell frame to allow gas discharge, then the pressure relief function is improved, but the risk of fire entering adjacent cells through the same holes increases

Engineering Contradiction:
Improvegas pressure reliefVSAvoidfire entry risk
Core Design Contradiction:
Stress or pressureVSObject-affected harmful factors

Solution Approach 1:

The screen member is positioned specifically at the exposure holes with localized functional properties. The screen member material and structure are designed to be permeable to gas molecules while being impermeable to fire and thermal runaway. This local quality differentiation allows the same component to simultaneously achieve pressure relief and fire protection functions at different scales.

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The screen member functions as a thin film or mesh structure that covers the exposure holes. This flexible yet resilient structure allows gas molecules to pass through while physically blocking larger fire particles and thermal runaway propagation. The screen member can deform under pressure but maintains its barrier function, enabling dynamic pressure relief while sustaining fire protection.

Inventive Principle:
Principle #30Flexible shells and thin films

3Object-affected harmful factors

If a screen member is used to seal exposure holes, then the fire protection is improved, but the gas discharge function may be blocked when not needed

Engineering Contradiction:
Improvefire protectionVSAvoidgas discharge capability
Core Design Contradiction:
Object-affected harmful factorsVSStress or pressure

Solution Approach 1:

The screen member is designed with dynamic characteristics that allow it to adapt its state based on operating conditions. Under normal conditions, the screen member maintains a sealed position to prevent fire entry. When gas pressure builds up, the screen member dynamically opens or deforms to allow gas passage, then returns to its sealed state when pressure is relieved. This dynamic behavior enables the same component to provide both fire protection and gas discharge functions as needed.

Inventive Principle:
Principle #15Dynamics

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 prevents fire or thermal runaway from propagating to adjacent cells by ensuring safe discharge of gases, enhancing the safety and stability of the battery module by ensuring gases are directed outside and not recycled into other cells.

Implementation Method 1

a vent unit that is opened to discharge gas to the outside when an internal pressure increases over a predetermined level

Methodology Applied
Scientific EffectPressure-driven gas discharge: Pressure Gradient

Implementation Method 2

configured to open a region thereof corresponding to the exposure hole by a gas pressure when gas is discharged from the vent unit of the battery cell

Methodology Applied
Scientific EffectGas pressure acting on solid material: Pressure Increase

Data Source

PatentEP4057434B1Battery module, battery pack comprising same, and automobile
Publication Date: 2024.10.02 LG ENERGY SOLUTION LTD
  • EP4057434B1 patent drawingFigure 1
  • EP4057434B1 patent drawingFigure 2
  • EP4057434B1 patent drawingFigure 3

AI summary

Disclosed is a battery module with enhanced stability against fire and explosion, a battery pack comprising the same and a vehicle. The battery module includes a plurality of battery cells configured to have electrode terminals respectively formed at one end and the other end thereof and have a vent unit that is opened to discharge gas to the outside when an internal pressure increases over a predetermined level; a cell frame configured to have an accommodation space for accommodating the plurality of battery cells and have a plurality of exposure holes opened so that the gas discharged from the battery cell moves to the outside; a screen member fixed to the cell frame to seal the exposure hole and configured to open a region thereof corresponding to the exposure hole by a gas pressure when gas is discharged from the vent unit of the battery cell; and a protection plate configured to fix the screen member and have a plurality of communication holes located corresponding to the exposure holes.