Battery Pack Upper Cover Venting for Thermal Runaway Gas Release
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional battery packs face thermal runaway issues due to the explosion-proof valve failing to open in time, leading to uncontrolled gas release and potential explosions.
Innovation Solution
The proposed upper cover assembly features a dual-exhaust unit system, where the first exhaust unit is located on the top plate and the second exhaust unit is on the side plate, both communicating with an exhaust vent. This design allows for directional gas discharge, ensuring quick release of high-temperature gases.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If an explosion-proof valve is provided in the upper cover to release pressure, then the battery pack can discharge gas during rapid gas swelling, but the explosion-proof valve often cannot open in time, causing high-temperature or sparked gas to accumulate and spread thermal runaway
Solution Approach 1:
The exhaust system is segmented into multiple independent exhaust units distributed at different locations (top plate and side plate) of the upper cover. Each exhaust unit includes exhaust holes that directly communicate with the external environment, eliminating the single-point failure risk of traditional explosion-proof valves and ensuring timely gas discharge from multiple directions simultaneously.
Solution Approach 2:
The exhaust system transitions from a single-point vertical exhaust (top-only) to a multi-dimensional exhaust structure with exhaust units on both the top plate and side plates. This spatial distribution creates multiple exhaust pathways in different directions, enabling comprehensive gas discharge and preventing thermal runaway spread through enhanced ventilation efficiency.
2Productivity
If a single explosion-proof valve is used, then the structure is simple, but the exhaust efficiency is insufficient and gas cannot be discharged quickly enough
Solution Approach 1:
The exhaust system is divided into multiple exhaust units with multiple exhaust holes distributed across different surfaces of the upper cover. This segmentation increases the total exhaust area and provides parallel discharge pathways, significantly enhancing gas discharge speed while maintaining relatively simple individual unit structures that are easy to manufacture.
Solution Approach 2:
Multiple exhaust units are combined on the upper cover, integrating both top and side exhaust functions into a unified system. The exhaust units work simultaneously to discharge gas, achieving high exhaust efficiency without requiring complex control mechanisms or movable parts, thus balancing productivity improvement with structural simplicity.
3Reliability
If the upper cover is hermetically sealed, then the battery pack is protected from external contamination, but gas generated during battery malfunction cannot be discharged, leading to internal pressure buildup and potential explosion
Solution Approach 1:
The upper cover maintains hermetic sealing overall but incorporates localized exhaust regions with exhaust holes at specific positions (top and side plates). These localized non-sealed areas allow gas to escape while the majority of the cover remains sealed, protecting against external contamination. The exhaust holes are strategically positioned to maximize pressure relief without compromising overall structural integrity and safety.
Solution Approach 2:
The exhaust holes act as intermediary channels between the sealed battery pack interior and the external environment. These controlled openings provide a designated pathway for gas discharge, mediating between the need for hermetic sealing (safety) and the need for pressure relief. The exhaust units serve as the interface that allows selective communication while maintaining overall system protection.
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 dual-exhaust unit system effectively directs gas release, preventing thermal runaway by ensuring timely discharge of high-temperature gases, thereby reducing the risk of explosions in battery packs.
Implementation Method 1
the first exhaust unit is disposed on the top plate, the second exhaust unit is disposed on the side plate, and the first exhaust unit communicates with the exhaust vent through the second exhaust unit
Data Source
AI summary
This application relates to the technical field of energy storage devices, and in particular, to an upper cover assembly and a battery pack. The upper cover assembly includes: an upper cover body, including a top plate and a side plate connected to an outer periphery of the top plate, wherein an exhaust vent is provided in the side plate; and an exhaust unit, including a first exhaust unit and a second exhaust unit that communicates with each other, wherein the first exhaust unit is disposed on the top plate, the second exhaust unit is disposed on the side plate, and the first exhaust unit communicates with the exhaust vent through the second exhaust unit. The upper cover assembly provided in this application allows gas (in battery cells) to be quickly discharged from the first exhaust unit and the second exhaust unit to the exhaust vent.