Secondary Battery Cap Structure for Controlled Venting
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing secondary batteries face limitations in increasing battery capacity due to shape restrictions, moisture ingress, and instability, particularly in controlling gas emission and flame direction during abnormal conditions.
Innovation Solution
A secondary battery design featuring an electrode assembly surrounded by a flexible exterior film and sealed with rigid caps, which provides structural stability, reduces moisture ingress, and controls gas and flame emission during abnormal conditions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Ease of manufacture
If a pouch film is molded to form a pouch cell, then the battery can be assembled, but cracks occur in the pouch film during molding and the film is discarded after degassing
Solution Approach 1:
The pouch cell structure is segmented into multiple components: a container formed by cup-molding upper and lower cases, a pouch film accommodating the electrode assembly, and a sealing structure. This segmentation allows each component to perform its specific function without bearing excessive stress, preventing cracks in the pouch film during molding and assembly.
2Ease of manufacture
If the pouch cell structure is used with cup-molded cases and pouch film, then assembly is achieved, but the venting direction cannot be controlled or predicted when internal pressure increases or explosion occurs
Solution Approach 1:
A venting structure is introduced as an intermediary component between the sealed pouch cell and the external environment. This structure includes a venting hole through which gas can be safely emitted in a controlled direction, preventing uncontrolled explosion while maintaining the sealed structure's integrity during normal operation.
3Quantity of substance
If the existing pouch cell design is used, then basic functionality is achieved, but battery capacity cannot be increased due to limited moldable depth of the pouch film
Solution Approach 1:
The design parameters of the container are changed by cup-molding the upper and lower cases to specific shapes that provide greater depth and volume. This allows the pouch film to accommodate a larger electrode assembly, increasing battery capacity while maintaining structural integrity through the rigid case support.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The present invention relates to a secondary battery, a method for manufacturing the same, and a battery pack including the same. The secondary battery according to an aspect of the present invention may include: an electrode assembly extending in one direction; an exterior film configured to surround a portion of the electrode assembly; and a cap configured to surround a remaining portion of the electrode assembly, wherein the cap may include: a cover part configured to cover one side in an extension direction of the electrode assembly; a connection part including a coupling portion which is provided on an outer surface of the cover part and is coupled to the exterior film; and a terminal part of which at least a portion is exposed to the outside of the cover part and which is electrically connected to the electrode assembly.