Secondary Battery Safety Member for Arcing Prevention
Solution Overview
Problem
Secondary batteries face challenges in preventing corrosion and ensuring safety during nail penetration or crush due to the electrical connection between the terminal and cap plate, which can lead to arcing and reduced sealing efficiency.
Innovation Solution
Incorporating safety members with a smaller sectional area and high contact resistance, such as hemispherical, pyramidal, or trapezoidal shapes, between the terminal and cap plate, and using insulating molding resin to enhance sealing and assembly efficiency, while ensuring the same electric potential for the terminal and cap plate.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the terminal is directly electrically connected to the cap plate, then electrical conductivity is improved, but corrosion resistance deteriorates due to arcing during nail penetration or crush
Solution Approach 1:
A safety member is introduced as an intermediary component between the terminal and the cap plate. This safety member includes an apex that contacts the terminal and a contact portion that contacts the cap plate, creating an intermediate connection path that prevents direct electrical contact between the terminal and cap plate, thereby eliminating arcing and improving corrosion resistance
Solution Approach 2:
The electrical connection path is segmented into two separate contact points: one between the safety member's apex and the terminal, and another between the safety member's contact portion and the cap plate. This segmentation breaks the direct electrical pathway, preventing current flow and arcing during penetration or crush events
2Reliability
If safety members with high contact resistance are used, then safety is improved by limiting current flow, but electrical conductivity deteriorates
Solution Approach 1:
The contact resistance parameter of the safety member is specifically optimized to be high (e.g., greater than 1 ohm) to limit current flow during penetration or crush events. This parameter change ensures that even if the battery is penetrated, the high contact resistance prevents dangerous current flow, thereby improving safety
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 effectively reduces corrosion, limits current flow during penetration or crush, and improves the safety and efficiency of the battery by preventing arcing and enhancing sealing efficiency.
Implementation Method 1
Incorporating safety members with a smaller sectional area and high contact resistance, such as hemispherical, pyramidal, or trapezoidal shapes, between the terminal and cap plate
Implementation Method 2
using insulating molding resin to enhance sealing and assembly efficiency
Data Source
Figure 1a
Figure 1b
Figure 1c
AI summary
A secondary battery (100) including an electrode assembly (110); a case (120) accommodating the electrode assembly (110); a cap plate (130) coupled with the case (120); a terminal (141) electrically connected to the electrode assembly (110) and extending through a terminal hole (131) of the cap plate (130); and at least one safety member (160, 160a, 160b, 160c, 260, 260a, 260b, 260c, 360, 360a, 360b, 360c, 460, 460a, 460b, 460c, 560, 660, 760, 860, 960, 1060, 1160, 1260) between the terminal (131) and the cap plate (120), the safety member having an apex with a base and a top smaller than the base, the base being electrically connected to one of the cap plate (130) and the terminal (141) and the top contacting the other of the cap plate (130) and the terminal (141) to electrically connect together the cap plate (130) and the terminal (141).