Battery Pouch Forming Punch for Stable Vertex Thickness

Solution Overview

Problem

Existing rechargeable battery pouch forming technologies face challenges in securely accommodating stack type electrode assemblies, particularly in ensuring sufficient thickness at the vertex areas where side walls and the bottom connect, leading to potential structural weaknesses and safety issues.

Innovation Solution

The rechargeable battery pouch forming device employs a punch with specifically designed corner rounds and 3D rounds that form vertex areas, ensuring a stable thickness by matching the curvature and length of these features with the die, thereby securely accommodating both winding and stack type electrode assemblies.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If conventional punch designs are used for forming pouches, then the forming process is simple, but the vertex areas have insufficient thickness leading to structural weaknesses

Engineering Contradiction:

Improvethickness uniformity at vertex areasVSAvoidpunch design complexity

Core Design Contradiction:

Manufacturing precisionVSDevice complexity

Solution Approach 1:

The punch design incorporates different curvature radii at different locations: larger curvature radii (first, second, third curvature radii) at corner regions and smaller curvature radii (fourth, fifth, sixth curvature radii) at other regions. This local differentiation ensures sufficient material thickness at vertex areas where side walls connect to the bottom, while maintaining forming efficiency in other areas.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention applies curved surface geometry to the punch by defining multiple rounded corners with specific curvature radii. The vertex areas are formed with three-dimensional rounded shapes characterized by first, second, and third curvature radii that are larger than the fourth, fifth, and sixth curvature radii, creating a spherical-like geometry that prevents stress concentration and ensures uniform thickness distribution.

Inventive Principle:

Principle #14Spheroidality (Curvature)

2Reliability

If larger curvature radii are used at corner rounds, then vertex area thickness is improved, but the punch design becomes more complex

Engineering Contradiction:

Improvestructural integrity of pouchVSAvoidpunch configuration complexity

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The punch design incorporates different curvature radii at different locations: larger curvature radii (first, second, third curvature radii) at corner regions and smaller curvature radii (fourth, fifth, sixth curvature radii) at other regions. This local differentiation ensures sufficient material thickness at vertex areas where side walls connect to the bottom, while maintaining forming efficiency in other areas.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The punch features asymmetric corner rounding where the first, second, and third curvature radii are deliberately made larger than the fourth, fifth, and sixth curvature radii. This asymmetric design specifically targets the vertex areas that require enhanced thickness for structural reliability, rather than applying uniform rounding throughout the punch geometry.

Inventive Principle:

Principle #4Asymmetry

3Manufacturing precision

If the punch has multiple different curvature radii, then vertex area formability is enhanced, but manufacturing the punch becomes more difficult

Engineering Contradiction:

Improvevertex area thickness controlVSAvoidpunch fabrication ease

Core Design Contradiction:

Manufacturing precisionVSEase of manufacture

Solution Approach 1:

The punch design incorporates different curvature radii at different locations: larger curvature radii (first, second, third curvature radii) at corner regions and smaller curvature radii (fourth, fifth, sixth curvature radii) at other regions. This local differentiation ensures sufficient material thickness at vertex areas where side walls connect to the bottom, while maintaining forming efficiency in other areas.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The invention specifies particular parameter relationships: the first, second, and third curvature radii are larger than the fourth, fifth, and sixth curvature radii. These parameter changes are designed to optimize the forming process by controlling material flow and thickness distribution at critical vertex areas, while the parameters remain within manufacturable ranges for standard punching equipment.

Inventive Principle:

Principle #35Parameter changes

Data Source

PatentUS20240387853A1Rechargeable battery and pouch forming device thereof

Publication Date: 2024.11.21 SAMSUNG SDI CO LTD

AI summary

A rechargeable battery pouch forming device, including a die supporting a first surface of a pouch base material to form the pouch base material for a rechargeable battery having a first opening, a stripper holding a second surface of the pouch base material supported on the die having a second opening larger than the first opening, and a punch that descends from the second surface side of the pouch base material through the second opening and the first opening to form a pouch by forming the pouch base material, the punch including a first round at a first corner of a first direction to form a vertex area, a second round at a second corner of a second direction crossing the first direction, a third round at a third corner of a third direction crossing the second direction.