Fluorescent-Coated Battery Separator for Fold Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During the preparation of lithium-ion batteries, separators can accidentally fold, causing a short circuit between the positive and negative electrode plates, which affects battery safety and reduces yield.
Innovation Solution
A separator with a fluorescent coating on specific regions is used to identify folds, and a color sensor monitors the fluorescent color to prevent folded separators from being incorporated into batteries, thereby increasing yield.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a separator is used without fluorescent coating, then the manufacturing process is simple, but folded separators cannot be identified and lead to short circuits
Solution Approach 1:
The patent applies fluorescent coating to the separator that changes optical properties when folded. The fluorescent material absorbs UV light and emits visible light, but when the separator is folded, the fluorescent coating becomes misaligned or obscured, causing the fluorescent signal to disappear or change. This color/optical property change enables automatic detection of folded separators without complex structural modifications to the separator itself.
Solution Approach 2:
The patent introduces fluorescent coating as an intermediary substance on the separator surface. This coating acts as a mediator between the separator's physical state (folded or not) and the detection system. The fluorescent coating translates the mechanical folding state into an optical signal that can be easily detected by sensors, solving the detection problem without modifying the separator's core structure.
2Reliability
If manual inspection of separators is performed, then folded separators can be detected, but production efficiency is reduced
Solution Approach 1:
The patent replaces manual mechanical inspection with an automated optical detection system. Instead of workers visually examining separators, a UV light source and fluorescent sensor automatically detect the presence or absence of fluorescent signals. This substitution eliminates the trade-off between detection accuracy and production speed, as the automated system can inspect separators at high speed without sacrificing accuracy.
Solution Approach 2:
The separator with fluorescent coating essentially inspects itself. The fluorescent coating on the separator interacts with UV light to produce a detectable signal that automatically indicates whether the separator is folded or not. This self-indicating property eliminates the need for external inspection efforts, allowing the separator to 'report' its own condition passively as it moves through the production line.
3Measurement precision
If fluorescent coating is applied to the separator, then folded separators can be identified, but manufacturing complexity increases
Solution Approach 1:
The fluorescent coating leverages optical property changes rather than structural changes to achieve fold detection. By applying a thin layer of fluorescent material to the separator surface, the patent creates a simple yet effective detection mechanism. The coating process is straightforward and does not require complex manufacturing steps, maintaining ease of manufacture while achieving high measurement precision in fold detection.
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 identifies and prevents folded separators from being used in lithium-ion batteries, enhancing safety and production efficiency by ensuring accurate identification and exclusion of faulty separators.
Implementation Method 1
at least one surface of the first region and/or at least one surface of the second region is provided with a fluorescent coating, and the fluorescent coating is used to identify whether the separator is folded or not
Data Source
AI summary
The present application provides a separator, a secondary battery, a battery module, a battery pack and an electrical apparatus. The separator may sequentially include a first region, a main region and a second region in a first direction. At least one surface of the first region and/or at least one surface of the second region may be provided with a fluorescent coating. The fluorescent coating may be used to identify whether the separator is folded or not.