Battery Pack Mechanical Power Cutoff for Collision Isolation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In electric vehicles, battery packs can deform during collisions, leading to potential fires due to short circuits. The battery management system (BMS) must cut off power, but if it fails, the risk of electric shock or short circuits increases.
Innovation Solution
A battery pack design that includes a frame, multiple battery modules, a battery disconnect unit (BDU), and a power cutoff portion. The power cutoff portion features a guide plate, power terminals, a connector portion, and a weight member that automatically blocks the electrical connection between the battery modules and the BDU during a vehicle collision.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the battery management system (BMS) is used to cut off power during collision, then the power cutoff operation can be performed, but the BMS may fail due to battery pack impact and the cutoff operation may not be performed
Solution Approach 1:
The power cutoff function is segmented into two independent systems: the BMS (electrical control) and the mechanical power cutoff device (physical impact response). This segmentation ensures that if one system fails, the other can still perform the cutoff function, thereby improving reliability without excessive complexity.
Solution Approach 2:
The mechanical power cutoff device acts as an intermediary between the collision impact and the electrical connection. It uses a weight member that moves under impact force to physically separate the connector portion from the power terminals, providing a direct mechanical response that bypasses the need for electrical system intervention during critical failure scenarios.
2Object-affected harmful factors
If the contactor remains in a closed state due to BMS failure, then the battery pack structure is simple, but the risk of electric shock or short circuit increases
Solution Approach 1:
The mechanical power cutoff device is pre-configured with the weight member positioned to be moved by collision impact. The guide plate and connector portion are pre-arranged so that when impact occurs, the weight member automatically moves to separate the electrical connection, performing the protective action before damage can occur without requiring complex real-time control systems.
Solution Approach 2:
The collision impact, which is a harmful event, is converted into a beneficial force that activates the weight member to move and separate the electrical connection. The impact force that would otherwise cause damage is utilized to trigger the protective cutoff mechanism, eliminating the need for additional sensors or control systems.
3Reliability
If a mechanical power cutoff device is added to the battery pack, then the power can be automatically blocked during collision, but the device complexity increases
Solution Approach 1:
The mechanical power cutoff device is merged with the existing battery pack structure by integrating the weight member, guide plate, and connector portion into the housing and electrical connection system. This consolidation allows the new functionality to be achieved without adding separate independent components, thereby minimizing the increase in overall device complexity.
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
The solution effectively prevents accidents such as explosions by automatically disconnecting power to the battery pack during a collision, thereby reducing the risk of electric shock or short circuits.
Implementation Method 1
a weight member movable along the guide plate in an event of a vehicle impact, the weight member being configured to transfer an impact force of the vehicle to the connector portion
Implementation Method 2
a connector portion slidably inserted between the first power terminal and the second power terminal and configured to electrically connect the first power terminal and the second power terminal to each other
Data Source
AI summary
A battery pack includes a frame portion configured to be installed in a vehicle, with a plurality of battery modules accommodated in the frame portion. A battery disconnect unit (BDU) is installed inside of the frame portion, with the battery disconnect unit being configured to transmit or block a voltage of the battery module. A power cutoff portion is configured to electrically connect the battery disconnect unit and the battery module and to block an electrical connection of the battery module and the battery disconnect unit in an event of a vehicle collision.