Battery Module Cover Layout for Venting Without Terminal Exposure
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
In battery modules, when the exterior container pressure increases, the cover member can be blown off, exposing bus bars and voltage detection lines, leading to potential electrical short circuits due to materials with metal adhering to these components.
Innovation Solution
A battery module design featuring a cover member with a first region of higher strength above electrode terminals and a second region of lower strength above gas-discharge valves, which can be selectively broken to prevent electrical short circuits by allowing gas discharge without exposing critical components.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If the cover member is made strong to protect electrode terminals, then protection of critical components is improved, but gas discharge capability deteriorates when pressure increases
Solution Approach 1:
The cover member is designed with non-uniform thickness, creating a weak portion with smaller thickness than other portions. This local quality variation allows the cover to maintain overall strength while having a specific localized area that can rupture to discharge gas, resolving the contradiction between overall strength and localized gas discharge capability.
2Stress or pressure
If the cover member is opened to discharge gas, then pressure relief is improved, but electrical short circuit risk worsens due to exposed bus bars and voltage detection lines
Solution Approach 1:
A protective film is introduced as an intermediary layer between the external environment and the electrode terminals. This film allows gas to pass through during normal operation but prevents direct contact between discharged materials and the electrical components, thus enabling pressure relief while maintaining electrical isolation and preventing short circuits.
Solution Approach 2:
The protective film is pre-installed to cover the electrode terminals before any gas discharge event occurs. This preliminary protective measure ensures that when the weak portion ruptures and gas is discharged, the electrode terminals are already protected, preventing potential short circuits from materials that may be discharged.
3Ease of manufacture
If the cover member is made uniform in strength, then manufacturing simplicity is improved, but selective gas discharge capability deteriorates
Solution Approach 1:
The cover member incorporates a localized weak portion with reduced thickness compared to the rest of the structure. This creates a predetermined rupture point that will fail first under pressure, enabling controlled gas discharge. The manufacturing process includes specific steps to create this thickness variation, balancing the added complexity with the benefit of controlled failure behavior.
Data Source
AI summary
A battery module includes: a plurality of battery cells arranged in a first direction; and a cover member provided above the plurality of battery cells. Each of the plurality of battery cells includes a housing having a gas-discharge valve, and an electrode terminal provided on the housing. The cover member includes a first region and a second region having a strength lower than a strength of the first region. The first region is located above at least one of the electrode terminals. The second region is located above at least one of the gas-discharge valves.