Power Storage Package Sealing for Lid Corner Leak Prevention

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Solution Overview

Problem

There is a need for improved sealability between the corners of lids and the outer package film in electrical storage devices to enhance the manufacturing process and overall device performance.

Innovation Solution

A method for manufacturing electrical storage devices that includes a sealing process using a sealing device to bond the lid and outer package film, with additional processes such as resealing, controlled pressing, and positioning to ensure a secure seal, and the use of a positioning device for precise alignment during winding and connection of electrode terminals.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a sealing device is used to bond the lid and outer package film, then the sealability is improved, but the manufacturing process complexity increases

Engineering Contradiction:
ImprovesealabilityVSAvoidmanufacturing process complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The sealing process is divided into multiple sequential sealing operations that bond adjacent sealing surfaces one by one. This segmentation allows each sealing operation to focus on a specific area, improving sealability while maintaining manageable process complexity through systematic division of the sealing task

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The lid is heated in a process carried out earlier than the sealing process, which prepares the lid for optimal sealing conditions before the actual bonding occurs. This preliminary heating action ensures the lid material is at the appropriate temperature for bonding, improving sealability without adding complex sealing mechanisms

Inventive Principle:
Principle #10Preliminary action

2Strength

If the lid is heated before sealing, then the bond strength is improved, but the energy consumption increases

Engineering Contradiction:
Improvebond strengthVSAvoidenergy consumption
Core Design Contradiction:
StrengthVSUse of energy by moving object

Solution Approach 1:

The lid is heated in advance before the sealing process to prepare it for optimal bonding conditions. This preliminary heating ensures the lid material reaches the appropriate temperature for strong adhesion to the outer package film, improving bond strength while allowing the sealing process itself to proceed efficiently

Inventive Principle:
Principle #10Preliminary action

Solution Approach 2:

The heating process changes the temperature parameter of the lid to an optimal range for bonding. By controlling the temperature parameter before sealing, the material properties of the lid are optimized for adhesion, achieving strong bonds without requiring excessive energy during the actual sealing operation

Inventive Principle:
Principle #35Parameter changes

3Reliability

If multiple sealing surfaces are bonded in order, then the seal completeness is improved, but the manufacturing time increases

Engineering Contradiction:
Improveseal completenessVSAvoidmanufacturing time
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The sealing process bonds multiple sealing surfaces in a systematic sequence, addressing each adjacent sealing surface individually. This segmentation ensures complete sealing coverage while organizing the multi-step process to minimize total manufacturing time through efficient sequencing

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The sealing device moves continuously to bond adjacent sealing surfaces in order, maintaining continuous useful action throughout the sealing process. This continuous operation ensures all sealing surfaces are addressed without interruption, improving seal completeness while optimizing manufacturing time through uninterrupted processing

Inventive Principle:
Principle #20Continuity of useful action

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 method allows for the suitable manufacturing of electrical storage devices with enhanced sealability, reducing the risk of leaks and improving the overall integrity and performance of the device.

Implementation Method 1

a sealing process of forming the seal portion using a sealing device

Methodology Applied
Scientific EffectHeat sealing: Heating

Implementation Method 2

an amount of pressing of the sealing device with respect to the outer package film and the lid is controlled

Methodology Applied
Scientific EffectPressure bonding: Compression

Implementation Method 3

positioning of the lid with respect to at least either the electrode terminal or the electrode assembly is performed by a positioning device

Methodology Applied
Scientific EffectPositioning:

Implementation Method 4

a first sealing process of forming the seal portion while moving either the sealing device or the lid with respect to the other

Methodology Applied
Scientific EffectRelative motion sealing:

Data Source

PatentEP4679581A1Method for producing power storage device, and power storage device
Publication Date: 2026.01.14 DAI NIPPON PRINTING CO LTD
  • EP4679581A1 patent drawingFigure 1A~2
  • EP4679581A1 patent drawingFigure 3~4
  • EP4679581A1 patent drawingFigure 5~6

AI summary

Disclosed is a method for producing a power storage device that comprises an electrode body and an outer package in which the electrode body is sealed. The outer package comprises: an outer package film which enfolds the electrode body in such a manner that an opening is formed; a cover member which is disposed at the position of the opening; and a sealing part at which the cover member and the outer package film are joined to each other. This method for producing a power storage device comprises a sealing step in which the sealing part is formed using a sealing device, and the sealing step comprises a first sealing step in which the sealing part is formed, while moving one of the sealing device and the cover member relative to the other one.