Optical Battery Pack Pressure Sensing for Thermal Runaway Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery systems lack effective methods to promptly detect thermal runaway conditions, which can lead to irreversible damage and potential explosions due to rapid temperature increases and gas ejection, posing significant safety risks.
Innovation Solution
A thermal runaway detection system within the battery pack utilizing a sensor unit with a first and second cover element forming a measurement chamber, containing a light emitter and sensor, which detects pressure changes through light path interruption, coupled with a control unit to analyze data and trigger safety measures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If traditional temperature monitoring is used to detect thermal runaway, then the detection system is simple, but the detection speed and reliability are insufficient due to the rapid temperature increase during thermal runaway
Solution Approach 1:
The patent replaces traditional temperature-based detection with an optical detection system. A light source emits light through a window in the battery housing, and a photodetector measures light transmission. During thermal runaway, gas expansion bends the window, altering light transmission characteristics. This mechanical-optical substitution enables faster, more reliable detection without complex electronic sensors inside the battery.
Solution Approach 2:
The patent introduces an intermediary measurement chamber filled with gas that transmits light between the light source and photodetector. The bending window modulates the light signal in response to pressure changes during thermal runaway. This intermediary mechanism translates internal battery pressure changes into detectable optical signals without requiring direct contact with hazardous battery materials.
2Measurement precision
If pressure sensors are installed inside the battery pack to detect thermal runaway, then the detection accuracy is improved, but the device complexity and potential interference with battery cells increase
Solution Approach 1:
The patent replaces direct mechanical pressure sensing with an optical sensing mechanism. Instead of placing pressure sensors inside the battery pack that could interfere with cell operation, the system uses a bending window to modulate light transmission. This indirect optical measurement achieves pressure detection precision without the complexity and interference risks of direct pressure sensor installation.
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
Enables early detection of thermal runaway, allowing for timely intervention and safety measures, reducing the risk of damage and fire by monitoring pressure changes and gas release within the battery pack.
Implementation Method 1
a light emitter and a light sensor arranged within the space such that light emitted from the light emitter is receivable at the light sensor via a light path that extends across the space
Implementation Method 2
the first cover element is designed to bend towards the second cover element and into the light path in the event of a pressure increase in the battery pack
Data Source
Figure 1~2
Figure 3~4
AI summary
The present disclosure refers to a battery system for an electric vehicle, an electric vehicle including the same, and a method for determination of a thermal runaway in the battery system. The battery system includes a battery pack including a plurality of battery cells accommodated within a housing. The battery system further includes a thermal runaway detection system including a sensor unit and a control unit. The sensor unit and control unit are configured for transmitting and receiving data from the sensor unit to the control unit. The sensor unit is positioned within the battery pack of the battery system and includes a first cover element and a second cover element arranged on and connected to the first cover element in such a way that a space is formed between the first cover element and second cover element; a light emitter and a light sensor arranged within the space such that light emitted from the light emitter is receivable at the light sensor via a light path that extends across the space; and the first cover element is designed to bend towards the second cover element and into the light path in the event of a pressure increase in the battery pack. The control unit is configured to detect a possible thermal runaway based on a change in data transmitted by the sensor unit.