Battery Pack Cell-Level Fusing Arc Suppression
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In battery packs, unintended short circuits can lead to arcing, which may cause damage and thermal runaway due to uncontrolled fuse blowing, especially in large packs with closely packed cells, resulting in increased cost, complexity, and weight in attempts to mitigate these risks.
Innovation Solution
Designing a battery pack where specific fusible interconnects associated with a single battery or cell have lower impedance than others, ensuring they are the last to fuse during a short circuit, and employing arc suppression systems such as non-conductive isolation, capacitors, thyristors, or permanent magnets to minimize sustained arcing.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional fusing methods are used in battery packs, then circuit protection is provided, but the risk of arcing and thermal runaway increases
Solution Approach 1:
The battery pack is divided into multiple independent cell groups, each with its own fusible interconnect. This segmentation ensures that a short circuit in one group does not propagate to other groups, isolating the fault and preventing cascading thermal runaway events across the entire battery pack.
Solution Approach 2:
Different interconnect designs are used for different cell groups based on their specific locations and risk profiles. The controller can selectively activate arc suppression mechanisms for specific interconnects that are at higher risk, rather than implementing uniform protection across all interconnects, thereby optimizing protection while minimizing overhead.
2Object-affected harmful factors
If multiple arc suppression mechanisms are implemented, then arcing risk is reduced, but cost and complexity increase
Solution Approach 1:
The system employs passive arc suppression mechanisms that automatically activate when needed without requiring active control. For example, fusible interconnects automatically blow to break circuits during overcurrent events, and non-conductive barriers passively prevent arc propagation without requiring power or control logic, thereby reducing system complexity.
Solution Approach 2:
Arc suppression mechanisms are pre-positioned and pre-configured in the battery pack design before operation. Non-conductive barriers are pre-installed in strategic locations, and the controller is pre-programmed with suppression algorithms, so that when an arc event occurs, the suppression action is immediately available without requiring complex real-time decision-making or additional components.
3Reliability
If cell-level fusing is implemented, then thermal runaway propagation is prevented, but manufacturing complexity increases
Solution Approach 1:
The battery pack is organized into discrete cell groups with dedicated fusible interconnects for each group. This modular segmentation allows for standardized manufacturing processes where each cell group can be assembled and tested independently before being integrated into the full battery pack, thereby managing manufacturing complexity through modularity.
Solution Approach 2:
The fusible interconnects serve multiple functions: they provide electrical connection between cells, act as overcurrent protection devices, and serve as isolation barriers during thermal runaway events. This multi-functionality reduces the need for separate components for each function, thereby simplifying the overall manufacturing process despite the enhanced safety capabilities.
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
This approach minimizes the risk of damage, excessive heating, and thermal runaway while maintaining battery pack performance, reliability, and safety with minimal impact on cost, complexity, weight, and size.
Implementation Method 1
The risk of sustained arcing for the predetermined interconnect(s) is minimized through the use of rapid clearing interconnects
Implementation Method 2
The battery pack includes an electrically non-conductive isolation structure that separates a selected cell from other cells in the battery pack
Data Source
AI summary
A battery pack, or battery pack module, is provided that achieves improved battery pack performance, system reliability and system safety while impacting only a small region of the battery pack/battery module, and thus having only a minor impact on battery pack cost, complexity, weight and size. The battery pack/battery module is designed such that the fusible interconnects associated with a single battery, or a specific fusible interconnect associated with a single battery, will be the last interconnect(s) to fuse during a short circuit event. The risk of sustained arcing for the predetermined interconnect(s) is minimized through the use of rapid clearing interconnects. As a result, the risk of damage and excessive heating is also minimized.