Zigzag Separator Electrode Assembly for Battery Gas Venting

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Gas traps in electrode assemblies of secondary batteries cause capacity degradation, increased cell resistance, and lithium precipitation, reducing the reliability of the battery.

Innovation Solution

An electrode assembly design featuring a separator sheet with a zigzag folding part and cover parts that include through-holes, allowing gases to be discharged, preventing gas traps and improving reliability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional electrode assembly structure is used, then the manufacturing process is simple, but gas traps form causing capacity degradation and lithium precipitation

Engineering Contradiction:
Improvebattery reliabilityVSAvoidseparator sheet structure
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The separator sheet is divided into multiple functional regions: a folding part that creates ventilation channels and multiple accommodation spaces, and a cover part with through-holes for gas discharge. This segmentation allows different portions of the separator to perform specialized functions (structural support, gas venting, electrode accommodation) that collectively prevent gas traps while maintaining overall system reliability.

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The folding part of the separator sheet acts as an intermediary structure that creates ventilation channels between electrode layers. This intermediate folding structure mediates gas flow paths, preventing direct contact between gas pockets and electrode surfaces, thereby eliminating gas traps without requiring fundamental changes to the battery assembly process.

Inventive Principle:
Principle #24Intermediary (Mediator)

2Object-generated harmful factors

If the separator sheet includes folding parts and cover parts with through-holes, then gas discharge is facilitated, but the manufacturing process becomes more complex

Engineering Contradiction:
Improvegas trap formationVSAvoidmanufacturing process
Core Design Contradiction:
Object-generated harmful factorsVSEase of manufacture

Solution Approach 1:

The separator sheet is pre-formed with folding parts and through-holes before battery assembly. This preliminary preparation of the separator structure allows gas discharge pathways to be established in advance, preventing gas trap formation during subsequent battery operation without adding complex steps to the assembly process itself.

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The separator sheet exhibits local quality variations: the folding part contains localized bends creating ventilation channels, while the cover part contains localized through-holes for gas discharge. These localized structural modifications are concentrated in specific regions rather than distributed throughout, minimizing overall manufacturing complexity while effectively addressing gas trap formation at critical locations.

Inventive Principle:
Principle #3Local quality

3Speed

If through-holes are formed in the cover part, then gas can be discharged quickly, but the structural integrity of the separator may be compromised

Engineering Contradiction:
Improvegas discharge speedVSAvoidseparator structural integrity
Core Design Contradiction:
SpeedVSStrength

Solution Approach 1:

The cover part of the separator sheet incorporates through-holes that create a controlled porous structure. This porous design allows gas to discharge rapidly through defined pathways while the surrounding intact separator material maintains structural integrity, preventing both gas traps and structural failure.

Inventive Principle:
Principle #31Porous materials

Data Source

PatentEP4715954A1Electrode assembly and manufacturing method thereof
Publication Date: 2026.03.25 LG ENERGY SOLUTION LTD
  • EP4715954A1 patent drawingFigure 1
  • EP4715954A1 patent drawingFigure 2~3
  • EP4715954A1 patent drawingFigure 4

AI summary

An electrode assembly includes a separator sheet including a folding part folded in a zigzag shape to define a plurality of accommodation spaces separated in the vertical direction, and a cover part extending from the folding part and a cell structure accommodated in the plurality of accommodation spaces of the separator sheet. The cell structure includes a first electrode and a second electrode. The cover part of the separator sheet includes a first side cover part covering a first side surface of the cell structure, and the first side cover part includes a first through-hole communicating with at least one accommodation space of the plurality of accommodation spaces of the separator sheet.