Battery Pack Fuse Layout for Fast High-Voltage Current Interruption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional protecting devices for lithium ion secondary batteries face challenges in safely and quickly interrupting current paths during high voltage and large current applications, due to the risk of electrode damage and extended blow-out time of the fuse element.
Innovation Solution
The protecting device incorporates an insulating substrate with a fuse element, a heat-generator, a heat-generator feeding electrode, an insulating layer, and a heat-generator lead-out electrode. The heat-generator lead-out electrode is designed such that the overlapping area with the heat-generator is smaller on the high potential side than on the low potential side, reducing the likelihood of spark occurrence and allowing for safe and quick current path interruption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If the heat-generator lead-out electrode has a large overlapping area with the heat-generator on the high potential side, then the thermal connection is improved, but the likelihood of spark occurrence increases
Solution Approach 1:
The patent applies local quality by creating asymmetric overlapping areas of the heat-generator lead-out electrode with the heat-generator. The overlapping area on the low potential side is made larger to optimize thermal connection, while the overlapping area on the high potential side is made smaller to reduce spark risk. This localized differentiation of geometric properties resolves the contradiction between thermal efficiency and spark prevention.
Solution Approach 2:
The patent directly applies asymmetry by designing the heat-generator lead-out electrode with unequal overlapping areas on opposite sides of the heat-generator. The asymmetric configuration creates different thermal coupling strengths on the high potential side versus the low potential side, allowing simultaneous optimization of heat transfer (on the low potential side) and spark suppression (on the high potential side).
2Power
If the protecting device is designed for large current capacity, then the current handling capability is improved, but the blow-out time of the fuse element is extended
Solution Approach 1:
The patent applies parameter changes by modifying the geometric parameters of the heat-generator lead-out electrode, specifically the overlapping area with the heat-generator. By optimizing this geometric parameter, the thermal connection efficiency is enhanced, which accelerates the heating rate of the fuse element. This allows the system to handle large currents while reducing the blow-out time, resolving the contradiction between current capacity and response speed.
3Use of energy by moving object
If the overlapping area of the heat-generator lead-out electrode with the heat-generator is increased, then the heat transfer efficiency is improved, but the risk of electrode damage increases
Solution Approach 1:
The patent applies local quality by differentiating the overlapping area of the heat-generator lead-out electrode with the heat-generator across different spatial locations. The larger overlapping area on the low potential side maximizes heat transfer efficiency, while the smaller overlapping area on the high potential side minimizes electrode damage risk. This localized optimization resolves the contradiction between heat transfer and reliability.
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 configuration reduces the likelihood of spark occurrence and enables safe and quick interruption of the current path, even under high voltage conditions, thereby preventing accidents such as fire.
Implementation Method 1
a heat-generator 4 formed on the insulating substrate 2 to blow the fuse element 3 by heat generation
Data Source
AI summary
To provide a protecting device and a battery pack using the same, which are less likely to cause a spark even when a high voltage is applied and can safely and quickly interrupt the current path. A protecting device includes: an insulating substrate 2; a fuse element 3; a heat-generator 4 which generates heat to blow the fuse element 3; a heat-generator feeding electrode 5 which serves as a power-feeding terminal to the heat-generator 4; an insulating layer 6 which covers the heat-generator 4; and a heat-generator lead-out electrode 7 which is formed along the heat-generator 4 on the insulating layer 6 and holds the melted conductor 3a of the fuse element 3, wherein, when the heat-generator 4 is energized, the heat-generator feeding electrode 5 side thereof works as a high potential portion and the heat-generator lead-out electrode 7 side thereof works as a low potential portion, and in the heat-generator lead-out electrode 7, an overlapping area in which a distal end portion 7a extending in the high potential portion side of the heat-generator 4 overlaps the heat-generator 4 is smaller than an overlapping area in which a proximal end portion 7b extending in the low potential portion side of heat-generator 4 overlaps the heat-generator 4.