Battery Electrode-Separator Adhesion Near the Electrode Terminal
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In secondary batteries like lithium ion batteries, the adhesive force between electrode plates and separators is lower at the outer peripheral portions due to heat dissipation, leading to unintended detachment and increased resistance, particularly affecting the electrode terminal area, which decreases battery output performance.
Innovation Solution
A secondary battery design where the electrode plate and separator are thermally adhered with a higher heat application per unit area near the electrode terminal portion compared to other areas, enhancing adhesive strength in that region.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If uniform thermal compression is applied to the stack of electrode plates and separator, then the manufacturing process is simple, but adhesive force between electrode plate and separator decreases at the outer peripheral portion due to heat dissipation
Solution Approach 1:
The patent applies different thermal compression conditions to different regions of the electrode assembly. Specifically, the thermal compression device applies greater heat and pressure to the outer peripheral portions (first and second regions) compared to the central portion, creating non-uniform local quality in the adhesion process. This resolves the contradiction by ensuring sufficient adhesive force at the outer periphery where heat dissipation occurs, while maintaining manufacturing feasibility through a controlled thermal compression process.
2Productivity
If thermal compression is applied from above and below, then the stacking process is efficient, but heat dissipation at outer peripheral portions reduces adhesive strength
Solution Approach 1:
The thermal compression device is designed to apply non-uniform thermal compression, with higher heat and pressure applied to the outer peripheral portions (first and second regions) than to the central portion. This local quality approach ensures that the outer periphery, which experiences greater heat dissipation, receives enhanced thermal energy to maintain reliable adhesive strength, while the central portion receives standard compression. This resolves the contradiction by maintaining stacking efficiency while ensuring adhesive reliability across all regions.
3Ease of manufacture
If adhesive force is insufficient at electrode terminal portion, then manufacturing is easier, but detachment occurs increasing resistance and decreasing output performance
Solution Approach 1:
The patent specifically targets the outer peripheral portions including the electrode terminal region by applying enhanced thermal compression to these areas. The thermal compression device applies greater heat and pressure to the first and second regions (outer periphery) compared to the central portion, ensuring that the electrode terminal portion achieves sufficient adhesive force. This prevents detachment at critical current concentration areas, maintaining battery output performance while keeping the manufacturing process feasible.
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
This approach improves adhesive strength between the electrode plate and separator near the electrode terminal, thereby stabilizing the distance between plates and maintaining battery output performance.
Implementation Method 1
a separator adhered to the electrode plate... in the thermally adhering, an amount of heat applied to the first region per unit area is larger than an amount of heat applied to the second region per unit area
Data Source
AI summary
A secondary battery includes: an electrode plate including a main body portion and an electrode terminal portion protruding from the main body portion along a first direction; and a separator adhered to the electrode plate, wherein the main body portion of the electrode plate includes a central region located in a vicinity of a center in the first direction, a first region located on a side close to the electrode terminal portion with respect to the central region in the first direction, and a second region located on a side opposite to the first region with respect to the central region in the first direction, and adhesion strength per unit area between the electrode plate and the separator in the first region is higher than adhesion strength per unit area between the electrode plate and the separator in the second region.