Battery Tab Adhesive Layering for Vibration Fracture Resistance

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Conventional tab adhesives in secondary batteries are hard, leading to stress concentration and fracture of the metal strip during mechanical vibrations due to their inability to deform, causing partial tab fracture and potential leakage.

Innovation Solution

A multi-layer tab adhesive structure with a first adhesive layer having a greater projection area than a second adhesive layer, where the adhesive overflow from the second layer falls onto the first layer, reducing stress concentration and fracture risk.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Strength

If a hard tab adhesive is used to secure the metal strip, then the tab is firmly fixed, but stress concentration occurs at the interface during mechanical vibrations leading to tab fracture

Engineering Contradiction:
Improvefixing strength of tabVSAvoidresistance to fracture during vibration
Core Design Contradiction:
StrengthVSReliability

Solution Approach 1:

The tab adhesive is divided into multiple layers with different properties: a first adhesive layer directly on the metal strip and a second adhesive layer on the first layer. This segmentation allows each layer to perform different functions - the first layer provides flexible bonding to reduce stress concentration, while the second layer provides structural support and firm fixation, thereby resolving the contradiction between fixing strength and fracture resistance

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Different regions of the tab adhesive structure are given different local qualities. The first adhesive layer has softer, more flexible properties to accommodate stress and prevent fracture at the critical metal strip interface, while the second adhesive layer has harder, more rigid properties to provide overall structural support and secure fixation, thus achieving both strong fixing and vibration resistance

Inventive Principle:
Principle #3Local quality

2Stability of the object's composition

If the tab adhesive is made hard to maintain structural integrity, then positioning is stable, but deformation of the metal strip is restricted causing stress concentration and fatigue

Engineering Contradiction:
Improvestructural integrity of tabVSAvoiddeformation capability during vibration
Core Design Contradiction:
Stability of the object's compositionVSAdaptability or versatility

Solution Approach 1:

The adhesive structure is segmented into layers with different mechanical properties. The first adhesive layer possesses softer characteristics that allow it to deform and accommodate stress during vibrations, protecting the metal strip from fatigue. The second adhesive layer maintains structural integrity and positional stability. This segmentation enables the tab to simultaneously achieve structural stability and adaptive deformation capability

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

The tab adhesive structure exhibits dynamic characteristics where the first adhesive layer can dynamically deform in response to vibrational stresses, absorbing energy and preventing stress concentration. The second layer provides a stable structural framework. This dynamic response allows the tab to adapt to mechanical vibrations while maintaining overall structural integrity

Inventive Principle:
Principle #15Dynamics

Data Source

PatentEP4318786A1Electrode assembly and electrochemical apparatus
Publication Date: 2024.02.07 NINGDE AMPEREX TECHNOLOGY LTD
  • EP4318786A1 patent drawingFigure 1~1C
  • EP4318786A1 patent drawingFigure 2~2C
  • EP4318786A1 patent drawingFigure 3~3E

AI summary

An electrode assembly includes an electrode plate and a tab disposed on the electrode plate, where the tab includes a metal strip and a tab adhesive provided on the metal strip, and along a thickness direction of the tab, the tab adhesive includes a first adhesive layer provided on the metal strip and a second adhesive layer provided on the first adhesive layer, where a projection area of the first adhesive layer along the thickness direction of the tab is greater than a projection area of the second adhesive layer along the thickness direction of the tab.