Zigzag Electrode Assembly With Balanced Bonding to Reduce Bending
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional zigzag-shaped electrode assemblies experience bending issues due to differences in bonding strength between the upper and lower surfaces of the separator, leading to potential detachment and safety problems, and increased electrical resistance when subjected to heat and pressure.
Innovation Solution
The electrode assembly is designed with a zigzag-shaped separator, where the upper surfaces of the positive and negative electrodes have smaller bonding strengths than the lower surfaces, and the upper surfaces of the electrodes face each other with the separator interposed, ensuring balanced bonding strength across both surfaces.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If heat and pressure are increased to prevent bending of the electrode assembly, then bonding strength is improved, but separator permeability is reduced and electrical resistance rises
Solution Approach 1:
The invention applies different bonding strengths to different surfaces of the separator by controlling coating conditions. The first surface is coated with coating slurry under specific conditions to achieve a first bonding strength, while the second surface is coated under different conditions to achieve a second bonding strength that is 0.8 to 1.2 times the first bonding strength. This local differentiation resolves the contradiction by preventing bending without requiring excessive heat and pressure that would harm separator permeability.
2Stability of the object's composition
If coating conditions are adjusted to balance bonding strength, then bending is reduced, but manufacturing complexity increases
Solution Approach 1:
The invention controls bonding strength balance by adjusting coating parameters such as coating slurry composition, coating speed, and drying conditions for each surface. By optimizing these parameters, the bonding strength on the second surface is controlled to be 0.8 to 1.2 times that of the first surface, achieving bending reduction without significantly complicating the manufacturing process.
3Strength
If the separator is compressed to prevent detachment, then bonding strength is improved, but electrical resistance increases due to reduced permeability
Solution Approach 1:
The invention applies different bonding strengths to different surfaces of the separator, with the second surface having 0.8 to 1.2 times the bonding strength of the first surface. This local differentiation ensures adequate bonding without requiring excessive compression that would reduce separator permeability and increase electrical resistance.
Data Source
Figure 1~2
Figure 3~4
AI summary
The present disclosure provides an electrode assembly including a separator bent in a zigzag shape; a negative electrode disposed between first surfaces of the separator; and a positive electrode disposed between second surfaces of the separator, wherein each of the positive electrode and the negative electrode include an upper surface and a lower surface having smaller surface bonding strength than the upper surface, and the upper surface of the positive electrode is disposed to face the upper surface of the negative electrode with the separator interposed therebetween, to provide an electrode assembly having structurally reduced bending.