Stepped-Diameter Cylindrical Battery Can for Higher Capacity
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Increasing the diameter of the exterior housing can to enhance battery capacity leads to increased weight due to the need for thicker sealing assemblies, which compromises durability and manufacturing costs.
Innovation Solution
A cylindrical battery design with a larger outer diameter for the body part and a smaller outer diameter for the opening end, allowing for a sealing assembly that matches the opening end diameter, thus maintaining durability and reducing weight.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Quantity of substance
If the diameter of the exterior housing can is increased to enhance battery capacity, then the battery capacity is improved, but the weight of the sealing assembly increases due to the need for thicker sealing assemblies
Solution Approach 1:
The exterior housing can is designed with different diameters for different sections: the body part has a larger diameter (20 mm or more) to accommodate increased battery capacity, while the opening end has a smaller diameter to reduce the size and weight of the sealing assembly. This local differentiation allows each part to have optimal dimensions for its specific function.
Solution Approach 2:
The exterior housing can is segmented into two distinct parts with different diameters: the body part and the opening end. This segmentation allows the battery to achieve increased capacity through the larger body diameter while the smaller opening end diameter reduces the sealing assembly weight requirement.
2Reliability
If the diameter of the sealing assembly is increased to maintain durability against external impact, then the durability strength is improved, but the thickness of the sealing assembly must be increased
Solution Approach 1:
The opening end of the exterior housing can has a smaller diameter specifically at the sealing assembly location, which reduces the required thickness of the sealing assembly while maintaining adequate durability strength for the application.
3Strength
If the thickness of the sealing assembly is increased to increase caulking force and durability, then the durability strength is improved, but the weight of the cylindrical battery increases
Solution Approach 1:
The exterior housing can is designed with a smaller diameter at the opening end where the sealing assembly is located, which reduces the required thickness and weight of the sealing assembly while maintaining adequate strength through optimized local geometry.
Solution Approach 2:
The exterior housing can is divided into sections with different diameters, allowing the sealing assembly section to have a smaller diameter that reduces weight while the body section maintains larger diameter for capacity.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a cylindrical battery with which it is possible to suppress an increase in weight while increasing capacity. A cylindrical battery (10) includes: an electrode body comprising a positive electrode and a negative electrode, which are wound together via a separator; an electrolyte; a bottomed cylindrical outer can (20) for accommodating the electrode body and the electrolyte; and a sealing body (30) that is fixed to an open end portion (20B) of the outer can (20) by swaging and is for sealing the outer can (20). In regard to the outer can (20), the outer diameter of a body part (20A) for accommodating the electrode body is 20 mm or greater, and the outer diameter of the open end portion (20B) for accommodating the sealing body (30) is less than the outer diameter of the body part (20A).