Battery Pack Vent Spring Holder for Faster Thermal Event Closure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Pressure equalization devices in traction battery packs of electrified vehicles face challenges in preventing gas escape during battery thermal events, as existing solutions fail to efficiently close the gas path to prevent moisture and contaminants from entering or escaping.
Innovation Solution
A spring holder design for the pressure equalization device, featuring a housing with a valve and a spring made of shape-memory alloy, where the spring holder includes differently spaced openings to direct fluid towards the spring, allowing it to close the valve more rapidly during thermal events, thereby preventing gas escape.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If a conventional spring holder design is used, then the device structure is simple, but the valve closes slowly during battery thermal events allowing gas escape
Solution Approach 1:
The spring holder features non-uniform opening distributions with different densities in different regions. The first opening is positioned closer to the spring than the second opening, creating localized fluid concentration zones that accelerate spring response in critical areas without requiring uniform complexity throughout the entire structure.
Solution Approach 2:
The spring holder is divided into distinct functional zones with different opening patterns. The first region contains openings optimized for rapid fluid delivery to the spring, while the second region has different opening characteristics. This segmentation allows each zone to perform its specific function optimally, achieving fast valve closure without unnecessary overall complexity.
2Loss of time
If the spring is positioned far from the openings, then the spring holder structure is simpler, but the fluid takes longer to reach the spring delaying valve closure
Solution Approach 1:
The spring holder is designed with pre-positioned openings that direct fluid flow toward the spring's location before the thermal event occurs. The first opening is strategically placed to deliver fluid to the spring in advance, ensuring immediate spring response when the thermal event triggers valve closure, thereby minimizing response time.
Solution Approach 2:
The spring holder acts as an intermediary component that mediates between the fluid source and the spring. By incorporating strategically positioned openings, it accelerates fluid delivery to the spring without requiring direct contact or complex mechanical linkages, thus reducing time loss while maintaining structural simplicity.
3Reliability
If the valve closes slowly during thermal events, then the spring mechanism is simpler, but moisture and contaminants can enter or escape the battery pack
Solution Approach 1:
The spring holder implements local quality by concentrating openings in specific regions where fluid delivery is most critical for spring activation. The first opening is positioned to provide rapid fluid supply to ensure quick valve closure and reliable protection, while the second opening provides supplementary flow. This localized optimization achieves high reliability without requiring uniform complexity across the entire spring holder.
Solution Approach 2:
The spring holder is designed to cushion and prepare the spring for rapid action before the thermal event fully develops. The strategically positioned openings ensure fluid is already positioned to act on the spring at the critical moment, providing a buffer that ensures the valve closes fast enough to prevent contaminant ingress while maintaining a relatively simple overall structure.
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 spring holder design enhances the speed at which the valve closes, reducing the time for pressure equalization and preventing undesirable gas escape during battery thermal events, ensuring the integrity of the traction battery pack.
Implementation Method 1
a spring made of shape-memory alloy, where the spring holder includes differently spaced openings to direct fluid towards the spring, allowing it to close the valve more rapidly during thermal events
Data Source
AI summary
A traction battery pack may include an outer enclosure assembly. A traction battery pack may include a pressure equalization device received within a wall of the outer enclosure assembly. The pressure equalization device may include a housing and a valve configured to close a gas path through the housing during a battery thermal event of the traction battery pack. The valve may include a spring configured to urge the valve to close during the battery thermal event. The spring is held in place by a spring holder. The spring holder includes a first set of openings spaced-apart from the spring by a first distance, and a second set of openings spaced-apart from the spring by a second distance less than the first distance.