Battery Pack Sealing and Venting for Gas Release Without Air Ingress
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing battery packs face issues with explosion due to high gas jet speeds from battery cells and burning due to outside air inflow when gas is released, as well as inadequate waterproofing and sealing mechanisms.
Innovation Solution
A battery pack design featuring a circuit board, battery cells, shoulder screws with specific elastic members, and an exterior case configuration that includes a first and second elastic member to maintain a hermetically sealed state while allowing rapid gas release and preventing outside air ingress.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a hermetically sealed structure is used to prevent moisture entry, then waterproofness is improved, but gas release capability deteriorates when battery cell abnormality occurs
Solution Approach 1:
A gas discharge hole is preliminarily formed in the battery pack case before any abnormality occurs. This pre-established discharge path ensures that when gas generation is detected, the gas can immediately escape through the pre-prepared channel, resolving the contradiction between maintaining hermetic sealing for waterproofness and enabling rapid gas release for safety.
Solution Approach 2:
A gas discharge channel acts as an intermediary structure that selectively allows gas to pass through while maintaining the hermetic seal against moisture and air. The channel includes a gas discharge hole formed in the battery pack case and extends into the battery cell, creating a controlled pathway that mediates between the conflicting requirements of sealing and gas venting.
2Object-generated harmful factors
If gas is released from the battery pack to prevent explosion, then internal pressure is reduced, but outside air inflow causes burning
Solution Approach 1:
The gas discharge channel serves as a one-way intermediary that allows internal gas to escape to the external atmosphere while preventing external air from entering the battery pack. The channel structure, extending from the battery cell through the battery pack case, creates a pressure-driven flow path that naturally vents internal pressure without allowing reverse flow of outside air that could cause combustion.
Solution Approach 2:
The gas discharge mechanism converts the potentially harmful high-pressure gas buildup into a beneficial controlled release process. By providing a dedicated discharge path, the system transforms the dangerous pressure accumulation into a safe venting mechanism that protects the battery pack while preventing the harmful effect of outside air ingress and subsequent combustion.
3Object-affected harmful factors
If a blocking member is used to prevent outside air inflow, then burning is suppressed, but gas release capability is reduced when gas jet speed is high
Solution Approach 1:
The gas discharge hole is preliminarily formed with sufficient diameter and structural strength to handle high gas jet speeds before any abnormality occurs. This pre-engineered opening is designed to accommodate the maximum expected gas flow rate, ensuring that when gas generation occurs, the blocking member does not obstruct the rapid release needed to prevent explosion.
Solution Approach 2:
The gas discharge channel structure acts as an intermediary that simultaneously addresses both concerns: it provides a robust opening large enough to vent high-speed gas jets and prevent explosion, while its design (extending into the battery cell and positioned strategically) inherently restricts outside air from flowing backward into the battery pack, thus preventing combustion.
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
Prevents explosion by quickly releasing gas and restricts outside air entry, enhancing waterproofness and safety through effective sealing and rapid pressure equalization.
Implementation Method 1
a first elastic member is disposed in a compressed state at a contact portion between the upper case and the lower case, and a second elastic member is disposed in a compressed state between the head portion and the upper case
Data Source
AI summary
A battery pack includes: a battery cell; one or more shoulder screws having a head portion, a screw portion, and an intermediate portion between the head portion and the screw portion, the intermediate portion being larger than an outer diameter of the screw portion and smaller than an outer diameter of the head portion; and an exterior case including an upper case and a lower case fastened to each other with the one or the plurality of shoulder screws. A first elastic member is disposed in a compressed state at a contact portion between the upper case and the lower case, and a second elastic member is disposed in a compressed state between the head portion and the upper case.