Electrode Tab Connection with Safety Slurry
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium rechargeable batteries face instability and risk of explosion due to overcharge, high temperature, or external short circuits, with existing solutions either compromising battery performance or requiring additional installation processes.
Innovation Solution
An electrode assembly with a conductive adhesion portion between electrode tabs, incorporating a safety element material like a gas generation material or positive temperature coefficient material, applied as a slurry to ensure safety without increasing resistance in normal operation states.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a material is added inside the cell to control abnormal operation, then battery stability is improved, but battery performance deteriorates
Solution Approach 1:
The safety element material is applied locally only at the electrode tabs where connection occurs, rather than distributing material throughout the entire cell. This localized application provides safety functionality at critical points while minimizing interference with the bulk electrode active material and preserving battery performance.
Solution Approach 2:
The conductive adhesion portion acts as an intermediary layer between the electrode tabs and the electrode lead. This intermediate layer provides both mechanical connection and electrical conductivity while incorporating safety functionality, thus mediating between the structural requirements and safety requirements without directly interfering with the electrochemical performance.
2Reliability
If a PTC element or CID element is mounted at the outer side of the cell, then battery stability is improved, but device complexity increases
Solution Approach 1:
The safety element material is merged with the conductive adhesion portion that already exists in the battery structure. Instead of adding separate PTC or CID elements as distinct components, the safety functionality is integrated into the existing connection structure between electrode tabs and electrode lead, thereby combining multiple functions into a single element.
Solution Approach 2:
The conductive adhesion portion is designed to serve multiple functions simultaneously: providing mechanical connection between electrode tabs and electrode lead, ensuring electrical conductivity, and incorporating safety functionality through the safety element material. This multi-functionality eliminates the need for separate safety devices.
3Reliability
If a conductive adhesion portion with safety element material is applied, then battery stability is improved, but manufacturing precision requirements increase
Solution Approach 1:
The safety element material is applied in a slurry form rather than as a solid component. This parameter change in physical state allows the material to be easily coated and conform to the electrode tab surfaces, reducing the precision requirements for application compared to placing solid components with specific dimensional tolerances.
Solution Approach 2:
The slurry form of the safety element material allows it to self-level and conform to the electrode tab surfaces during application. The material's flow properties enable it to automatically distribute and adhere to the correct areas, reducing the need for highly precise external control during manufacturing.
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 electrode assembly effectively prevents abnormal operation states like overcharge by generating gas or increasing resistance, ensuring battery stability while maintaining performance and minimizing manufacturing complexity.
Implementation Method 1
A gas may be generated when the gas generation material reaches a decomposition voltage, thereby increasing a volume of the conductive adhesion portion.
Implementation Method 2
the conductive adhesion portion includes a safety element material, and wherein the safety element material is applied in the form of a slurry
Data Source
AI summary
An electrode assembly having an improved connection structure between electrode tabs includes: an electrode laminate including a plurality of unit cells, each unit cell of the plurality of unit cells formed of a positive electrode having an electrode tab extending from an end thereof, a negative electrode having an electrode tab extending from an end thereof, and a separator disposed between the positive electrode and the negative electrode; and a conductive adhesion portion connecting the electrode tabs of the positive electrode to each other or connecting the electrode tabs of the negative electrode to each other, wherein the conductive adhesion portion includes a safety element material, and wherein the safety element material is applied in the form of a slurry.