Battery Electrode Plate Thickness Gradient for Rolling Integrity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium ion battery electrode plates tend to drape or wrinkle during rolling due to mismatched extension rates of the electrode material and current collector, leading to performance issues and potential breakage, which affects the battery's yield and safety.
Innovation Solution
A battery electrode plate design featuring a squared current collector with distinct thickness regions and a transition region, where the electrode material thickness gradually decreases from a first thickness region to a second thickness region, coated uniformly, and an insulating layer covers the transition and second thickness regions to prevent draping and enhance safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Manufacturing precision
If electrode material is coated uniformly on the current collector, then the coating quality is improved, but the edges of the electrode material region extend during rolling causing draping and breakage
Solution Approach 1:
The electrode material thickness is designed to vary locally across the current collector surface. The coating thickness decreases from the center region toward the edge region, creating different thickness zones that accommodate differential expansion during rolling. This local variation in thickness prevents edge extension and draping while maintaining uniform coating quality in each specific region.
2Reliability
If the electrode material thickness is reduced at the edges, then rolling draping is prevented, but the coating process becomes more complex
Solution Approach 1:
The coating process controls the thickness parameter of the electrode material to vary continuously from the center to the edge of the current collector. By adjusting the coating parameters (such as coating speed, material flow rate, or head position) across different spatial locations, the desired thickness gradient is achieved. This parameter variation approach maintains rolling integrity while using a relatively simple coating process.
3Reliability
If a thickness gradient is introduced in the electrode material, then rolling breakage is prevented, but the manufacturing precision of thickness control becomes more difficult
Solution Approach 1:
The thickness gradient of the electrode material is established during the coating process itself, before the rolling operation. By pre-forming the gradient structure in the coated layer, the subsequent rolling process encounters uniform thickness conditions that prevent draping and breakage. This preliminary action eliminates the need for post-coating thickness adjustment and simplifies the overall manufacturing precision requirements.
Data Source
Figure 1~2
Figure 3
AI summary
The present invention discloses a battery electrode plate and a forming method thereof and a battery having the same. The battery electrode plate comprises squared current collector with electrode material being coated on at least a portion of the current collector, the portion thereof has a first thickness region, a second thickness region which has a thickness smaller than that of the first thickness region, and a transition region tapering from the first thickness region toward the sec ond thickness region. The present invention further discloses a method of forming the electrode plate and a battery having the same. The current collector in the present invention may not break or drape or wrinkle in rolling, and as a result, the yield rate of the electrode plate may be improved and is benefit for large scale industrial production. And the battery thus formed may have improved safety performance.