Pouch Battery Lead Sealing That Withstands Cell Swelling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The sealing of pouch cases in batteries is unreliable, leading to potential leakage of electrolyte and ingress of external particles due to the connection between the pouch case and electrode leads becoming loose or releasing during battery swelling.

Innovation Solution

The outer surface of the inflatable pouch case is sealingly bonded to the electrode leads, rather than the inner surface, allowing the pouch case to expand and accommodate gas, reducing the tension on the connection and improving sealing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the inner surface of the pouch case is bonded to the electrode leads, then the sealing connection is established, but the battery swelling causes tension that loosens the bonding and leads to leakage

Engineering Contradiction:

Improvesealing reliabilityVSAvoidbonding stability during swelling

Core Design Contradiction:

ReliabilityVSStability of the object's composition

Solution Approach 1:

Instead of bonding the inner surface of the pouch case to the electrode leads (conventional approach), the invention bonds the outer surface of the pouch case to the electrode leads. This inversion changes the direction of the bonding interface, allowing the pouch case to swell inward without creating tensile stress on the bonding connection, thereby maintaining sealing reliability during battery swelling

Inventive Principle:

Principle #13The other way round (Inversion)

Solution Approach 2:

The invention changes the bonding location parameter from the inner surface to the outer surface of the pouch case. This parameter change fundamentally alters how the pouch case interacts with swelling forces, transforming the bonding interface from a tension-prone location to a compression-resistant location that maintains stable bonding during battery operation

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the pouch case is sealed tightly to prevent leakage, then sealing is improved, but the battery cannot accommodate gas evolution during swelling

Engineering Contradiction:

Improvesealing reliabilityVSAvoidswelling accommodation capacity

Core Design Contradiction:

ReliabilityVSAdaptability or versatility

Solution Approach 1:

By inverting the bonding location to the outer surface, the pouch case can swell inward toward the battery components while the bonding connection remains on the outer surface. This allows the pouch case to accommodate gas evolution and swelling without compromising the sealing connection, as the swelling forces do not act on the bonding interface

Inventive Principle:

Principle #13The other way round (Inversion)

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

This configuration enhances the resistance to leakage by maintaining the connection integrity under pressure, reducing the likelihood of the pouch case detaching from the electrode leads during swelling.

Implementation Method 1

The outer surface of the inflatable pouch case is sealingly bonded to a surface of at least one electrode lead

Methodology Applied

Scientific EffectBonding: Adhesive

Data Source

PatentEP4712221A1Battery and method for manufacturing the battery

Publication Date: 2026.03.18 LG ENERGY SOLUTION LTD

Figure 1(a)~1(b)
Figure 2(a)~2(b)
Figure 3(a)~3(b)

AI summary

Disclosed is a battery, comprising battery components including an electrode assembly; an inflatable pouch case enclosing the battery components inside, the inflatable pouch case having an inner surface and an outer surface opposite to the inner surface; and at least one electrode lead electrically connected to the electrode assembly and extending through the inflatable pouch case from the inside of the inflatable pouch case to an outside of the inflatable pouch case. The outer surface of the inflatable pouch case is sealingly bonded to a surface of the at least one electrode lead.