Electrode Assembly Stiffness via Laser-Fused Wrapping Separator
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium secondary battery electrode assemblies experience bending issues due to insufficient adhesion between electrodes and separators, leading to potential interference with the battery case, necessitating an enhancement in stiffness to prevent such deformations.
Innovation Solution
An electrode assembly with a stack configuration where separators protrude beyond electrodes, wrapped by a separator that is fused with the edges of the inner separators using a laser beam, providing increased stiffness and minimizing bending.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the overall length of the stack-type electrode assembly is increased, then the battery capacity is improved, but bending occurs due to insufficient adhesion between the electrode and the separator
Solution Approach 1:
The patent divides the long electrode assembly into multiple segments by introducing a wrapping separator that circumferentially wraps around the stack at regular intervals. This segmentation provides localized support points along the length of the electrode assembly, preventing bending while maintaining the overall increased length for higher capacity.
Solution Approach 2:
The wrapping separator acts as a thin film structure that circumferentially wraps around the electrode stack. This thin film provides structural reinforcement and prevents bending of the long electrode assembly while maintaining flexibility for battery packaging and assembly.
2Stability of the object's composition
If the stiffness of the electrode assembly is increased to prevent bending, then structural stability is improved, but the complexity of the manufacturing process increases
Solution Approach 1:
The patent combines the function of the separator and the wrapping structure into a single integrated component. The wrapping separator both separates electrodes and provides structural reinforcement, eliminating the need for separate adhesive materials or additional stiffening structures, thus simplifying the manufacturing process.
Solution Approach 2:
The wrapping separator serves multiple functions simultaneously: it acts as a separator between electrodes, provides structural reinforcement to prevent bending, and serves as a wrapping structure for securing the electrode assembly. This multi-functionality reduces the number of components needed and simplifies manufacturing.
3Stability of the object's composition
If a wrapping separator is added to increase stiffness, then structural stability is improved, but the use of energy increases due to additional materials and processing
Solution Approach 1:
The patent optimizes the parameters of the wrapping separator including its length (greater than 0.5 times the stack length), width, and fusion characteristics to achieve the minimum necessary structural reinforcement. This parameter optimization ensures adequate stiffness while minimizing material usage and associated manufacturing energy consumption.
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 solution effectively enhances the stiffness of the electrode assembly, reducing the likelihood of bending and ensuring proper alignment, while also eliminating the need for separate adhesives and maintaining high energy density.
Implementation Method 1
fusing the edges of at least some of the plurality of separators with the wrapping separator by using a laser beam
Data Source
AI summary
An electrode assembly includes a stack, in which a plurality of electrodes and a plurality of separators are alternately stacked on each other and edges of the separators protrude further outward than the electrodes, and a wrapping separator, which surrounds the stack. The edges of at least some of the plurality of separators may be fused with the wrapping separator to form fused portions.