Stack-Folding Electrode Assembly With Separator Edge Insulation

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Lithium metal batteries face safety degradation due to lithium dendrite growth and dead lithium exposure during charging and discharging, leading to short circuits and reduced lifespan in stack-folding configurations.

Innovation Solution

Attaching insulation tape to the upper and lower sides of the folding separation film in a stack-folding type electrode assembly to prevent lithium dendrite exposure and suppress dead lithium protrusion, thereby maintaining battery integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If a stack-folding scheme is used for lithium metal battery, then energy capacity is improved, but lithium dendrites and dead lithium are exposed on upper and lower sides causing short circuits

Engineering Contradiction:
Improveenergy capacityVSAvoidshort circuit prevention
Core Design Contradiction:
Use of energy by moving objectVSReliability

Solution Approach 1:

An insulation tape is introduced as an intermediary component between the folding separation film and the external environment. This insulation tape specifically covers the upper and lower sides where lithium dendrites and dead lithium are exposed, preventing direct contact between these harmful elements and the positive electrode, thus resolving the short circuit issue while preserving the stack-folding configuration's energy capacity benefits

Inventive Principle:
Principle #24Intermediary (Mediator)

2Reliability

If insulation tape is attached to upper and lower sides of folding separation film, then lithium dendrite exposure is prevented, but device complexity increases

Engineering Contradiction:
Improveshort circuit preventionVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The insulation measure is segmented by applying insulation tape only to the specific upper and lower sides of the folding separation film where lithium dendrites are exposed, rather than insulating the entire battery structure. This targeted approach prevents short circuits while minimizing the increase in device complexity and maintaining manufacturing efficiency

Inventive Principle:
Principle #1Segmentation

Data Source

PatentEP3745521B1Stack-folding type electrode assembly and lithium metal battery comprising same
Publication Date: 2023.12.20 LG ENERGY SOLUTION LTD
  • EP3745521B1 patent drawingFigure 1
  • EP3745521B1 patent drawingFigure 2A
  • EP3745521B1 patent drawingFigure 2B

AI summary

The present invention relates to a stack-folding type of electrode assembly and a lithium metal battery including the same. In detail, according to an exemplary embodiment of the present invention, the lithium metal battery is realized as a stack-folding type, and the insulation tape is respectively attached to the upper side and the lower side of the folding separation film, thereby solving the drawback of exposure of the lithium dendrite and the dead lithium produced on the surface of the negative electrode during the charging and discharging process.