Secondary Battery Vent Plate Segmentation for Pressure Relief
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium ion secondary batteries face challenges in maintaining effective venting properties while preventing deformation when internal pressure increases, which can lead to safety issues and reduced performance.
Innovation Solution
A secondary battery design featuring a cap assembly with a vent plate having two plates of different rigidities and thicknesses, where the first plate is softer and thinner, and the second plate is stiffer and thicker, allowing for effective gas release while minimizing deformation during increased internal pressure.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If a single rigid vent plate is used to maintain structural integrity under pressure, then deformation is prevented, but venting effectiveness is reduced
Solution Approach 1:
The vent plate is segmented into two distinct plates: a first vent plate with lower rigidity for effective venting, and a second vent plate with higher rigidity for maintaining structural integrity under pressure. This segmentation allows each plate to perform its specialized function independently, resolving the contradiction between venting effectiveness and structural strength.
Solution Approach 2:
Different regions of the vent plate structure are assigned different rigidity qualities. The first vent plate region has lower rigidity to facilitate gas release, while the second vent plate region has higher rigidity to prevent deformation. This local differentiation of material properties allows the system to simultaneously achieve both venting effectiveness and structural integrity.
2Stability of the object's composition
If a thick rigid plate is used for the vent plate, then deformation is prevented, but venting properties are compromised
Solution Approach 1:
The vent plate is divided into two separate plates with different thicknesses. The first vent plate is thinner to allow for effective venting, while the second vent plate is thicker to provide deformation resistance. This segmentation resolves the contradiction by distributing different functional requirements to separate components.
Solution Approach 2:
The vent plate assembly functions as a composite structure combining two plates with different mechanical properties. This composite approach allows the system to achieve both venting effectiveness (through the thinner first plate) and deformation resistance (through the thicker second plate) simultaneously.
Data Source
AI summary
A secondary battery includes: a cylindrical case; an electrode assembly in the cylindrical case; and a cap assembly configured to seal the cylindrical case and including a cap-down electrically connected to the electrode assembly, a cap-up coupled to an upper portion of the cap-down, and a vent plate between the cap-down and the cap-up, wherein the vent plate includes: a first plate; and a second plate coupled to the outside of the first plate, wherein the first plate has rigidity less than that of the second plate.