Battery Pack Temperature Fault Detection Using Dual Thermistors
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery systems struggle to accurately distinguish between temperature increases caused by external environmental changes and malfunctions within the battery pack.
Innovation Solution
A battery system equipped with first and second detection devices to measure internal and external temperatures, respectively, and a control device to compare their rate of increase, determining whether the temperature rise is due to external changes or malfunctions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a single temperature detection device is used to monitor battery cell temperature, then the device complexity is reduced, but the measurement precision of temperature increase cause cannot be determined
Solution Approach 1:
The temperature monitoring system is segmented into two distinct detection devices: a first detection device monitoring battery cell temperature and a second detection device monitoring ambient temperature. This segmentation allows independent measurement of internal and external temperature conditions, enabling accurate identification of whether temperature increase originates from the battery cell or external environment.
Solution Approach 2:
The control device acts as an intermediary that receives temperature data from both detection devices, compares the temperature increase rates, and determines the cause of temperature increase. This intermediary processing enables differentiation between internal battery issues and external environmental factors without adding physical complexity to the sensing system.
2Measurement precision
If multiple detection devices are used to monitor both internal and external temperatures, then the measurement precision of temperature increase cause is improved, but the device complexity increases
Solution Approach 1:
The control device merges the data from multiple detection devices into a unified analysis process. By combining temperature readings from both the battery cell monitor and ambient temperature sensor, the system achieves accurate cause identification while consolidating the complexity into a single control unit rather than distributing it across multiple independent systems.
Solution Approach 2:
The control device performs multiple functions: it monitors battery cell temperature, monitors ambient temperature, compares temperature increase rates, and determines the cause of temperature increase. This multi-functionality reduces overall system complexity by consolidating multiple specialized devices into a single universal control unit.
3Measurement precision
If the first detection device is placed close to the battery cell for accurate internal temperature monitoring, then the measurement precision is improved, but the detection device is affected by gas discharge from the battery cell
Solution Approach 1:
The first detection device is positioned at a specific location that optimizes temperature monitoring while avoiding gas discharge paths. This localized placement strategy ensures the device remains close enough to accurately capture internal temperature changes but far enough from gas discharge points to avoid interference, achieving both measurement precision and resistance to harmful factors.
Solution Approach 2:
The system design acknowledges the presence of gas discharge as an inevitable phenomenon and positions the detection device to exploit the spatial relationship between gas discharge paths and temperature monitoring requirements. By strategically placing the sensor, the harmful gas discharge effect is converted into a design constraint that actually improves measurement accuracy by preventing direct contamination of the sensor while maintaining thermal coupling.
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 precise identification of the cause of temperature increases, distinguishing between external and internal factors with high accuracy.
Implementation Method 1
a first detection device that detects a first temperature indicating a temperature of the housing
Implementation Method 2
a second detection device that detects a second temperature indicating a temperature in the housing
Data Source
AI summary
A battery system includes: a battery stack; a housing that houses the battery stack and that is installed in a vehicle; a first thermistor that detects a first temperature of the housing; a second thermistor that detects a second temperature in the housing; and a battery ECU that compares a result of detection by the first thermistor with a result of detection by the second thermistor to determine whether a temperature increase in the battery stack is due to a change in an external environment of a battery pack or due to a malfunction in a battery cell.