Battery Pack Monitoring via PCM Phase Change Fault Detection
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery packs face challenges in detecting and managing faults such as cell imbalances, internal short circuits, and thermal runaway, leading to reduced performance and safety hazards due to undetected malfunctions.
Innovation Solution
A battery monitoring system utilizing a phase change material (PCM) that changes phase at a specific temperature, coupled with a phase change recognition device and control unit, to detect local phase changes and determine the state of each battery cell by imparting an electrical load and analyzing the presence or absence of phase changes.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If traditional monitoring methods are used for battery packs, then device complexity is reduced, but measurement precision and reliability of fault detection deteriorate
Solution Approach 1:
A phase change material (PCM) is introduced as an intermediary between battery cells and the monitoring system. The PCM absorbs heat from malfunctioning cells and undergoes phase change, which is then detected by temperature sensors. This intermediary mechanism amplifies subtle thermal signals into detectable phase transitions, significantly improving fault detection precision without requiring complex direct monitoring of each cell.
Solution Approach 2:
The system utilizes phase transitions of the PCM as a detection mechanism. When battery cells malfunction and overheat, the PCM absorbs the excess heat and transitions from solid to liquid phase. This phase change provides a clear, binary signal that is easily detectable by temperature sensors, enabling high-precision fault detection with simple sensing equipment.
2Measurement precision
If electrical load is imparted to detect phase changes, then measurement precision improves, but loss of energy increases
Solution Approach 1:
The electrical load is applied periodically rather than continuously. The control unit imparts electrical load at specific intervals to induce phase changes in the PCM, then pauses to allow the system to return to baseline. This periodic application minimizes total energy consumption while still providing sufficient stimulation to detect cell malfunctions through phase change observations.
Solution Approach 2:
The system performs preliminary detection using minimal electrical load before escalating to higher load levels. By first applying a small electrical load and observing whether phase changes occur, the system can identify obvious faults with minimal energy expenditure. Only when preliminary detection is inconclusive does the system apply higher loads, thus optimizing the balance between detection precision and energy loss.
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
Efficiently identifies malfunctioning battery cells by detecting local phase changes, preventing overheating and enabling timely replacement, thus ensuring reliable battery operation and safety.
Implementation Method 1
a phase change material having a phase change temperature, wherein each battery cell of the plurality of battery cells is in contact with the PCM, such that a local phase change occurs in the PCM, when the PCM is heated by an adjacent battery cell to or above the phase change temperature
Implementation Method 2
The PCM may have a latent heat of fusion of at least 100 J/g. The relevant phase change may be from a solid phase to a liquid phase and vice versa
Implementation Method 3
The control unit is configured to impart an electrical load on the battery pack, such that functional battery cells of the plurality of battery cells heat the PCM locally to or above the phase change temperature
Data Source
AI summary
A battery monitoring system includes a battery pack with a plurality of battery cells, a phase change material, at least one phase change recognition device configured to detect a local phase change of the PCM, and a control unit communicatively coupled to said phase change recognition device. Each battery cell is in contact with the PCM, such that the local phase change occurs in the PCM when the PCM is heated by an adjacent battery cell to or above a phase change temperature of the PCM. The control unit is configured to impart an electrical load on said battery pack, such that functional battery cells heat the PCM locally to or above said phase change temperature, and a respective state of each battery cell may be determined based on a detected presence or absence of local phase change determined by the phase change recognition device.