Waveform Edge Active Material Layer Battery Capacity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Variations in the width of the active material layer on collector plates in secondary batteries can lead to variations in battery capacity, affecting the performance and consistency of electric storage apparatuses.
Innovation Solution
The active material layer is formed with a predetermined width on a partial region of the collector plate, and a waveform is created on the edge of the layer, ensuring a width variation ratio between 0.03 and 0.056, which prevents capacity reduction and maintains consistency across multiple batteries.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If the active material layer is applied onto the collector plate, then the battery can be manufactured, but the width of the active material layer varies causing capacity variations
Solution Approach 1:
The invention introduces a waveform structure on the edge of the active material layer, transforming the traditional straight edge into a controlled undulating pattern. This parameter change in edge geometry allows the width variation to be predictable and manageable, ensuring that even with application process variations, the capacity remains within acceptable ranges by maintaining the width variation ratio within 3-56%
Solution Approach 2:
The waveform structure is applied locally at the edge region of the active material layer rather than uniformly across the entire layer. This local modification allows the majority of the active material layer to maintain consistent properties while the edge region compensates for width variations, thus resolving the contradiction between ease of manufacture and manufacturing precision
2Quantity of substance
If the width of the active material layer is increased to improve capacity, then more active material is used, but capacity reduction occurs due to edge effects
Solution Approach 1:
The invention applies a waveform (curved) structure to the edge of the active material layer instead of a straight edge. This curvature distributes the edge effects more evenly, preventing the harmful concentration of variations at a single straight boundary. The waveform allows the active material to be extended in quantity while maintaining capacity stability by reducing the negative impact of edge effects
3Area of stationary object
If the active material layer width is made larger than collector plate width, then coverage is improved, but edge effects adversely affect charge and discharge
Solution Approach 1:
The waveform edge structure transforms the harmful straight edge into a beneficial curved pattern. When the active material layer extends beyond the collector plate width, the waveform edge distributes the excess material in a controlled manner, allowing improved coverage area while the curved geometry mitigates the adverse edge effects that would otherwise occur at a straight boundary
Data Source
AI summary
An electric storage apparatus has a positive electrode plate, a negative electrode plate, and a separator. Each of the positive electrode plate and the negative electrode plate has a collector plate and an active material layer containing an electrolytic solution, and the active material layer is formed in a predetermined width on a partial region of a collector plate. The separator is placed between the positive electrode plate and the negative electrode plate and contains an electrolytic solution. At least one of the positive electrode plate and the negative electrode plate, an edge of the active material layer in a width direction has a waveform. A set value Wn of the width of the active material layer and a variation ΔW of the width of the active material layer satisfy a condition of 0.03≦ΔW/Wn≦0.056.