Laminated Battery Terminal Notch for Stable Pressure Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing laminated batteries face issues with inconsistent and inaccurate pressure release mechanisms, leading to unpredictable tearing of the outer casing when internal pressure exceeds permissible limits, due to variations in the formation of notch-shaped heat seal portions.
Innovation Solution
The laminated battery design incorporates a surface-roughened electrode terminal with a notch portion, allowing precise adjustment of the internal pressure at which the outer casing tears, by varying the width of the surface-roughened portion and notch shape with high accuracy, ensuring stable pressure release.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a notch-shaped heat seal portion is formed by adjusting seal width, then pressure release function is achieved, but manufacturing precision and reliability deteriorate due to high accuracy requirements
Solution Approach 1:
The invention changes the parameter of the electrode terminal by adding a surface-roughened portion with controlled arithmetic average height (0.1-30 μm) and introducing a notch portion with specific width ratios (0.3-0.7 times the terminal width). This transforms the pressure release mechanism from relying on precise heat seal width control to relying on the geometric parameters of the notch portion in the surface-roughened area, which are easier to control with standard manufacturing tolerances.
Solution Approach 2:
The surface-roughened portion acts as an intermediary element between the electrode terminal and the laminated film. The roughened surface creates a larger effective bonding area that compensates for variations in heat seal width, while the notch portion in this surface-roughened area serves as the stress concentration point for controlled tearing. This intermediary structure decouples the precision requirements from the final pressure release functionality.
2Ease of manufacture
If heat seal portion accuracy is low, then manufacturing is easier, but unreliable pressure release occurs at permissible pressure or fails to release when needed
Solution Approach 1:
The invention introduces new controllable parameters: the arithmetic average height of the surface-roughened portion (0.1-30 μm) and the notch portion width ratio (0.3-0.7 times terminal width). These parameters provide manufacturing flexibility and tolerance compensation, allowing reliable pressure release functionality to be achieved even when heat seal width varies within standard manufacturing tolerances.
3Reliability
If outer casing is designed to tear at high accuracy pressure point, then stable pressure release is achieved, but device complexity increases
Solution Approach 1:
The invention applies local quality by creating a surface-roughened portion only in the specific region where the laminated film bonds to the electrode terminal, rather than modifying the entire terminal. The notch portion is localized within this roughened area. This localized modification achieves the pressure release function without requiring complex structures throughout the entire electrode terminal assembly.
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
This design stabilizes the tearing of the outer casing at a predetermined pressure, reducing variations and maintaining high bonding strength while preventing metal powder scatter and electrolyte ingress, thus enhancing reliability and safety.
Implementation Method 1
the electrode terminal has a surface-roughened portion, which has an arithmetic average height higher than an arithmetic average height of another part
Implementation Method 2
the outer casing has a weld portion in which inner surfaces of the laminated films are stacked and welded together
Data Source
AI summary
The laminated battery disclosed herein includes an electrode body, an outer casing made of a laminated film which accommodates the electrode body, and an electrode terminal. The outer casing has a weld portion in which inner surfaces of the laminated films are stacked and welded together in a peripheral edge of space which accommodates the electrode body. The electrode terminal passes between the laminated films stacked on each other in the weld portion and is inserted into the outer casing, one end of the electrode terminal is electrically connected to the electrode body, and another end of the electrode terminal is exposed to outside of the outer casing. In addition, at least a part of the electrode terminal inserted into the outer casing is plate-shaped. In the plate-shaped portion, a surface-roughened portion having a notch portion is provided at a position of the weld portion.