Secondary Battery Compressing Member for Uniform Electrode Load
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional secondary batteries face issues with uniform load distribution on the wound electrode body due to case deformation, leading to insufficient battery performance and power generation capability, especially at the ends where higher rigidity causes gaps and reduced load application.
Innovation Solution
Incorporating a compressing member, such as thick portions on a film sandwiched between the electrode body and the case, which applies load on a wider area and ensures even pressure distribution, thereby overcoming the case deformation and gap issues.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Stability of the object's composition
If the case is made rigid to maintain structural stability, then the case deformation is reduced, but the load application on the electrode body becomes insufficient due to gap formation
Solution Approach 1:
A compressing member is introduced as an intermediary element between the case and the electrode body. This mediator transmits the binding load from the case to the electrode body effectively, ensuring sufficient load application even when the case maintains high rigidity to prevent deformation.
Solution Approach 2:
The compressing member is strategically positioned at specific locations where gap formation is most likely to occur, such as between the case and the electrode body winding. This localized intervention ensures that load is applied precisely where needed without requiring changes to the overall case structure.
2Productivity
If the binding load is increased to improve load distribution, then the battery performance is enhanced, but the case deformation increases leading to gap formation
Solution Approach 1:
The compressing member acts as a mediator that allows high binding load to be applied to the electrode body without transmitting excessive deformation to the case structure. It absorbs and distributes the compressive forces, maintaining both battery performance and case integrity.
Solution Approach 2:
The compressing member is pre-positioned between the case and electrode body to cushion against deformation before it occurs. This preventive measure allows the binding load to be applied effectively while the compressing member absorbs the deformation stress, preventing gap formation.
3Device complexity
If the pressing members are placed only at specific locations, then the device complexity is reduced, but the load distribution on the electrode body becomes insufficient
Solution Approach 1:
The compressing member is divided into multiple segments or sections that can be positioned at different locations around the electrode body. This segmentation allows load to be applied at multiple points without requiring a complex array of separate pressing members, maintaining simplicity while improving load distribution.
Solution Approach 2:
The compressing member is designed to serve multiple functions: it applies load to the electrode body, prevents gap formation, and accommodates the binding load from the case. This multi-functionality eliminates the need for additional specialized pressing members, reducing device complexity while ensuring adequate load distribution.
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 ensures sufficient load is applied across the entire electrode body, enhancing battery performance and power generation capability by eliminating load shortages and variations, resulting in improved performance of both individual batteries and battery assemblies.
Implementation Method 1
a compressing member that is located between an inner surface of the case and the electrode body and presses part of a surface of the electrode body
Data Source
AI summary
A secondary battery comprises a flat wound electrode body, a flat-type hard case housing the wound electrode body, and a film sandwiched between them. The film is formed with thick portions each of which is located at a boundary region between a flat portion and a curved portion of the surface of the wound electrode body. When a plurality of the secondary batteries are bound, therefore, load is applied widely on almost the entire wound electrode body, thereby enabling exertion of sufficient generation capability. Thus, a secondary battery with improved battery performance is provided in which load is sufficiently applied on an electrode body. The secondary battery can also be used as a battery assembly, a battery to be mounted on a vehicle, and a battery to be mounted on a battery mounting device.