Battery Module Connector Moisture Barrier for Humid Conditions

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Moisture ingress into battery modules can lead to short circuits and damage the sensing function of connectors, posing a risk of ignition, especially under high temperature and high humidity conditions.

Innovation Solution

A battery module structure featuring a moisture barrier film formed between the connector and the module frame, which guides and discharges moisture outside the module through an inclined extension portion and a passage between the insulating cover and end plate, preventing moisture from reaching the connector.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If the connector is formed in an open form to facilitate automated assembly of FFC, then the ease of manufacture is improved, but moisture can easily ingress into the connector causing short circuits and reliability deterioration

Engineering Contradiction:
Improveease of assemblyVSAvoidresistance to moisture ingress
Core Design Contradiction:
Ease of manufactureVSReliability

Solution Approach 1:

A moisture barrier member is introduced as an intermediary component between the connector and the module frame. This barrier member selectively blocks moisture ingress while allowing the connector to maintain its open, easily-assembled structure. The barrier member acts as a mediator that protects the connector from moisture without interfering with the automated FFC assembly process.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The moisture barrier member is implemented as a thin film or shell structure that conforms to the connector geometry. This flexible barrier effectively seals the connector opening against moisture while maintaining the structural integrity and electrical functionality of the connector. The thin film approach allows easy integration into the existing connector design without requiring complex structural modifications.

Inventive Principle:
Principle #30Flexible shells and thin films

2Extent of automation

If the connector has an open upper side structure, then automated robot arm assembly of FFC is enabled, but moisture condensation on the module frame can flow directly into the connector causing short circuits

Engineering Contradiction:
Improveautomated assembly capabilityVSAvoidmoisture ingress
Core Design Contradiction:
Extent of automationVSObject-affected harmful factors

Solution Approach 1:

The moisture barrier member serves as a protective intermediary positioned between the moisture source (condensation on module frame) and the vulnerable connector. It selectively blocks the harmful moisture while allowing the automated assembly process to proceed unchanged, as the barrier is integrated in a way that does not interfere with robot arm access or FFC connection.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The moisture blocking function is extracted as a separate, dedicated component (moisture barrier member) rather than being integrated into the connector structure itself. This separation allows the connector to maintain its open, automated-friendly design while the extracted barrier function provides selective protection against moisture ingress.

Inventive Principle:
Principle #2Taking out (Extraction)

3Reliability

If moisture proofing structures are added to protect the connector, then reliability is improved, but the device complexity increases

Engineering Contradiction:
Improveprotection against moistureVSAvoidstructural complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The moisture proofing is achieved using a thin film moisture barrier member that is structurally simple yet functionally effective. This approach avoids complex multi-component assemblies or bulky protective structures, maintaining device simplicity while providing reliable moisture protection. The thin film can be easily integrated into the existing module assembly process.

Inventive Principle:
Principle #30Flexible shells and thin films

Solution Approach 2:

The moisture barrier member is designed as a simple intermediary component that fits between existing structural elements (connector and module frame). This intermediary approach adds minimal complexity compared to redesigning the entire connector or module structure, as it leverages existing spaces and interfaces for moisture protection.

Inventive Principle:
Principle #24Intermediary (Mediator)

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 prevents moisture ingress, safeguarding the connector's sensing function and preventing short circuits, ensuring safe operation under humid conditions.

Implementation Method 1

A battery module structure featuring a moisture barrier film formed between the connector and the module frame, which guides and discharges moisture outside the module

Methodology Applied
Scientific EffectCapillary action: Capillary Action

Implementation Method 2

guides and discharges moisture outside the module through an inclined extension portion and a passage

Methodology Applied
Scientific EffectGravitational flow: Gravitation

Data Source

PatentEP4099490B1Battery module and battery pack including the same
Publication Date: 2025.11.12 LG ENERGY SOLUTION LTD
  • EP4099490B1 patent drawingFigure 1
  • EP4099490B1 patent drawingFigure 2
  • EP4099490B1 patent drawingFigure 3

AI summary

A battery module according to one embodiment of the present disclosure includes: a battery cell stack in which a plurality of battery cells are stacked; a module frame for accommodating the battery cell stack; a busbar frame formed at both ends of the battery cell stack, respectively; a connecting portion that connects the busbar frames arranged at both ends, respectively, and is formed of a flexible flat cable (FFC); and a connector formed on the busbar frame and coupled to the connecting portion, wherein a film portion is formed between the connector and the upper side portion of the module frame.