Battery Pack Protection Circuit for Cell Voltage and Temperature Control
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Battery packs often enter a failed state due to unstable voltage and temperature conditions, leading to ineffective charging and discharging, which existing technologies struggle to manage efficiently.
Innovation Solution
A battery pack system with a protection device and a battery management system (BMS) that permanently cuts off charging and discharging paths and compulsorily discharges battery cells when they exceed reference voltage or temperature thresholds, using voltage and temperature measuring devices to maintain stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the protection device permanently cuts off charging and discharging paths when abnormal conditions are detected, then battery safety is improved, but the battery pack cannot be restored and must be replaced
Solution Approach 1:
The protection device is divided into two independent parts: a first protection circuit that permanently cuts off charging/discharging paths for safety, and a second protection circuit that can be reset to restore functionality. This segmentation allows the system to maintain both safety through permanent protection and restoration capability through the resettable second circuit.
Solution Approach 2:
The second protection circuit is designed to be resettable, allowing the battery pack to recover from abnormal states without complete replacement. After an abnormal condition triggers protection, the system can recover by resetting the second protection circuit once the abnormality is resolved, discarding the temporary protective state in favor of normal operation.
2Reliability
If the battery pack discharges all cells when one cell exceeds voltage or temperature thresholds, then safety is improved, but energy waste increases
Solution Approach 1:
The protection device operates independently on each battery cell based on its own voltage and temperature conditions. When one cell exceeds thresholds, only that specific cell is discharged through its dedicated discharge path, while other cells within normal ranges continue to function normally. This localized approach maintains safety for abnormal cells without wasting energy from healthy cells.
Solution Approach 2:
The battery pack uses multiple independent discharge paths, each associated with a specific battery cell. This segmentation allows selective discharge of only the problematic cell rather than forcing discharge of the entire battery pack, thereby preserving energy in cells that do not require discharge.
3Reliability
If voltage and temperature thresholds are set low for early protection, then safety is improved, but operational time is reduced
Solution Approach 1:
The protection device dynamically monitors voltage and temperature of each battery cell in real-time and activates discharge only when specific abnormal thresholds are exceeded. This dynamic approach allows the battery to operate freely within safe ranges, maximizing operational time, while providing immediate protection when abnormal conditions arise, thus balancing safety and duration.
Data Source
AI summary
A battery pack including a plurality of battery cells and a method of controlling the battery pack are provided. The method includes: permanently cutting off charging and discharging paths of the battery pack; and discharging one or more of the battery cells when a condition of which satisfies a reference condition. Therefore, state of the battery pack changes from its failure state to a stable state.