Battery Sub-Pack Venting Structure for Ignition Containment
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Secondary battery cells generate heat during charging and discharging, leading to increased temperature and internal pressure, which can cause ignition and potential explosions, especially when multiple cells are mounted in devices like electric vehicles, resulting in uncontrolled flame propagation and safety risks.
Innovation Solution
A battery sub-packing unit design that includes a case with a sub-vent hole for flame and gas discharge to an external space, featuring a metal surrounding cover and insulating slit openings, along with an inner pad generating carbon dioxide or nitrogen to block oxygen inflow and extinguish flames, minimizing the risk of ignition propagation.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If battery cells are mounted in a compact arrangement to increase energy density, then productivity and space utilization are improved, but the risk of heat accumulation and ignition propagation increases
Solution Approach 1:
The patent divides the battery system into isolated sub-packing units, each containing individual battery cells separated by insulating materials. This segmentation prevents heat and ignition from propagating between cells, allowing compact arrangement while maintaining safety. The case structure creates discrete compartments that physically isolate each cell.
Solution Approach 2:
The patent introduces intermediary elements including insulating materials positioned between battery cells and a case structure surrounding each cell. These intermediaries act as thermal and electrical barriers, preventing direct heat transfer and ignition propagation while allowing the cells to be mounted in close proximity for high energy density.
2Reliability
If a sealed case structure is used to protect battery cells, then reliability is improved, but the ability to discharge internal pressure and flames externally is reduced
Solution Approach 1:
The patent incorporates vent holes in the case structure before ignition occurs, creating predetermined pathways for pressure and flame discharge. This preliminary anti-action prevents uncontrolled explosion by providing a safe escape route for internal pressure buildup, while the case remains sealed to protect cells from external damage.
3Reliability
If insulating materials are placed between battery cells to prevent ignition propagation, then safety is improved, but electrical connectivity for electrode tabs is compromised
Solution Approach 1:
The patent applies local quality by using insulating materials only in specific regions between battery cells where thermal isolation is needed, while leaving electrode tab regions exposed and accessible. The case structure provides localized insulation at cell boundaries while maintaining electrical connectivity paths for current collection, achieving both safety and operational functionality.
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 design effectively prevents the propagation of ignition and minimizes the impact of flames on adjacent cells and occupants by directing high-temperature and high-pressure flames and gases externally, enhancing safety in applications like electric vehicles.
Implementation Method 1
a lower end portion in which a sub-vent hole is formed for communication between the external space and an internal space in which the at least one battery cell is disposed
Implementation Method 2
an inner pad disposed in the internal space of the case, contacting the at least one battery cell accommodated in the case, and generating at least one of carbon dioxide or nitrogen during oxidation to block inflow of external oxygen
Implementation Method 3
an end panel on which an electrode tab of the at least one battery cell is fastened to extend into an external space
Data Source
AI summary
A battery sub-packing unit includes at least one battery cell; and a case accommodating the at least one battery cell, wherein the case comprises an end panel on which an electrode tab of the at least one battery cell is fastened to extend into an external space, and having a lower end portion in which a sub-vent hole is formed for communication between the external space and an internal space in which the at least one battery cell is disposed.