Spiral-Wound Button Cell Structure for Leak-Resistant Contacts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional button cells with stacked electrode-separator assemblies face issues such as complex and costly production, high scrap rates due to faulty connections, and susceptibility to leaks under axial mechanical loads.
Innovation Solution
The button cell features a housing with a flat bottom and top area, incorporating an electrode-separator assembly wound in a spiral shape. This assembly includes a positive electrode, a negative electrode, and a separator, with a metal foil output conductor making contact with the housing. A winding core provides axial contact pressure, enhancing electrical connection and mechanical robustness.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If stacked electrode-separator assemblies are used to fill the button cell housing, then the available area within the housing is optimally utilized, but the production becomes complicated and expensive with high scrap rates due to faulty connections
Solution Approach 1:
Multiple electrode-separator assemblies are merged into a single wound configuration. The patent describes winding the electrode-separator assembly in a spiral shape around a winding core, combining what would traditionally be multiple separate stacked assemblies into one continuous wound structure. This eliminates the need for multiple separate connections and reduces production complexity while maintaining optimal space utilization within the button cell housing.
2Quantity of substance
If stacked electrode-separator assemblies are used, then the available area within the housing is optimally utilized, but faults occur when assemblies make contact with one another increasing the scrap rate
Solution Approach 1:
The patent merges multiple electrode-separator assemblies into a single wound structure, eliminating the interfaces between separate assemblies where faults typically occur. The continuous wound configuration removes the contact points between stacked assemblies, thereby reducing the scrap rate while maintaining optimal space utilization.
Solution Approach 2:
The winding core serves as a protective element around which the electrode-separator assembly is wound. This core provides structural support and prevents defects from developing during the winding process and subsequent operation, cushioning against potential faults before they can occur.
3Ease of operation
If button cells have a stack of electrodes and separators, then the electrodes can be connected to the housing poles, but the button cells very quickly start to leak under axial mechanical loads
Solution Approach 1:
The patent transitions from a linear stacked configuration to a spiral wound configuration around a central core. This curved, radial arrangement distributes axial mechanical loads more evenly throughout the structure, preventing the localized stress concentrations that cause leaks in stacked designs. The spiral geometry provides inherent mechanical robustness while maintaining electrical connectivity.
4Ease of operation
If conventional stacked electrode assemblies are used, then electrical connections can be made, but material costs increase and space is occupied by connection materials
Solution Approach 1:
The patent combines multiple electrode-separator assemblies into a single wound structure, eliminating the need for separate connection materials and components for each assembly. The continuous wound configuration requires fewer connection points and less connection material, reducing both material costs and the space occupied by non-active materials.
Solution Approach 2:
The wound electrode-separator assembly serves multiple functions simultaneously: it provides electrical connectivity, structural support, and space-efficient packaging. The spiral configuration around the winding core integrates these functions into a single structure, eliminating the need for separate connection components and reducing overall material requirements.
Data Source
AI summary
A button cell includes a housing having a cell cup with a flat bottom area and having a cell top with a flat top area. The button cell also includes an electrode-separator assembly winding disposed within the housing. The electrode-separator assembly winding includes a multi-layer assembly that is wound in a spiral shape about an axis. The multi-layer assembly includes a positive electrode formed from a first current collector coated with a first electrode material, a negative electrode formed from a second current collector coated with a second electrode material, and a separator disposed between the positive electrode and the negative electrode. The button cell further includes a winding core around which the multi-layer assembly is wound. The winding core provides a contact pressure on a first metal foil output conductor in an axial direction to facilitate electrical contact between the first metal foil output conductor and the housing.