Battery Internal Short Test Cell With Embedded Metal Terminals
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing methods for testing internal shorts in secondary batteries, such as nail penetration and ISC devices, fail to accurately simulate the condition at room temperature and are limited by the wax layer's melting point, making it difficult to evaluate safety after long cycle or high temperature storage.
Innovation Solution
A method and apparatus for testing internal shorts in secondary batteries, where metal terminals are strategically placed to cause a controlled internal short, allowing for accurate simulation and measurement of short circuit current and resistance without relying on temperature-dependent wax layers, enabling evaluation at any desired state, including room temperature.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Temperature
If wax layer is used in ISC device to cause internal short, then internal short can be induced at high temperature, but internal short cannot be caused at room temperature and testing is limited by melting point
Solution Approach 1:
The patent removes the wax layer component from the ISC device, replacing it with a metal terminal that directly contacts the separator. This extraction eliminates the temperature-dependent melting mechanism and enables internal short induction across all temperature ranges, particularly at room temperature where the original wax-based system failed.
Solution Approach 2:
The invention changes the physical state and properties of the short-circuiting mechanism from a temperature-dependent wax layer to a temperature-independent metal terminal. This parameter change allows the device to function reliably across the entire temperature spectrum without being constrained by the melting point of any material.
2Ease of manufacture
If nail penetration method is used to induce internal short, then internal short can be caused easily, but it cannot perfectly simulate field conditions and causes over internal short
Solution Approach 1:
The patent applies local quality by placing the metal terminal at a specific location within the battery cell, allowing controlled contact with the separator at a defined point. This localized approach enables precise simulation of field conditions while avoiding the excessive and uncontrolled internal shorting caused by nail penetration methods.
Solution Approach 2:
The metal terminal acts as an intermediary element between the external testing apparatus and the internal battery components. It provides a controlled interface that enables accurate simulation of internal short conditions without the need for direct nail penetration, thereby improving both ease of manufacture and measurement precision.
3Reliability
If ISC device with wax layer is inserted into secondary battery, then internal short can be induced, but manufacturing process becomes complex and requires disassembly
Solution Approach 1:
The metal terminal is pre-installed within the battery cell during the manufacturing process, before the battery is sealed. This preliminary action eliminates the need for subsequent disassembly and insertion of ISC devices, simplifying the manufacturing process while maintaining reliable internal short induction capability.
Solution Approach 2:
The metal terminal serves multiple functions: it acts as both an electrical conductor and an internal short induction mechanism. This multi-functionality eliminates the need for separate ISC device components, reducing overall device complexity and streamlining the manufacturing process.
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 approach allows for precise simulation and evaluation of internal shorts in secondary batteries, ensuring safety assessment and design validation without the limitations of existing methods, enabling reliable safety evaluation and design improvements.
Implementation Method 1
When an internal short occurs, the shorted part is expanded by Joule heat involved in the short circuit current and abnormal heat generation occurs
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Provided is a secondary battery for testing an internal short, and a method and apparatus for testing an internal short of a secondary battery using the same. The secondary battery for testing an internal short according to the present disclosure includes a positive electrode side metal terminal having one end disposed between a positive electrode plate and a separator of the secondary battery, and a negative electrode side metal terminal having one end disposed between a negative electrode plate and the separator of the secondary battery, and is used to cause an internal short by contact between the other end of the positive electrode side metal terminal and the other end of the negative electrode side metal terminal. According to the present disclosure, it is possible to perform an internal short test in a desired state of the secondary battery after long cycle and high temperature storage without being affected by the testing temperature condition.