Secondary Battery Electrode Lead Venting Mechanism
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium secondary batteries face safety issues due to potential internal short circuits, overcharging, and gas generation, which can lead to deformation, explosion, or fire, necessitating improved venting mechanisms to manage pressure and prevent accidents.
Innovation Solution
The secondary battery design incorporates electrode leads with first and second vent holes, along with lead films, to create a path for gas discharge, ensuring that pressure is released externally through strategically located vent holes and folding grooves, enhancing safety by preventing pouch swelling and potential explosions.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If secondary batteries use liquid electrolytes to achieve high energy density, then energy density is improved, but safety deteriorates due to risk of internal short circuits, overcharging, and gas generation leading to explosion or fire
Solution Approach 1:
The patent pre-establishes vent holes in the electrode lead and lead films before abnormal situations occur. These vent holes are positioned to create a predetermined gas discharge path that activates only when internal pressure exceeds normal levels, allowing the battery to maintain safety features without affecting normal operation and energy density
Solution Approach 2:
The electrode lead and lead films act as intermediary components with built-in vent holes that mediate between the sealed pouch containing high-energy electrolytes and the external environment. This intermediary structure provides a controlled escape route for gas while maintaining the integrity of the sealed battery structure during normal operation
2Strength
If secondary batteries are sealed to prevent leakage and maintain structure, then structural integrity is improved, but safety deteriorates due to inability to release pressure from generated gas
Solution Approach 1:
The patent segments the sealed pouch structure by incorporating vent holes in the electrode lead and lead films, creating distinct regions: a sealed containment area for the electrolyte and electrode assembly, and controlled discharge pathways through the vent holes. This segmentation allows the pouch to maintain overall structural integrity while providing localized pressure release capabilities
Solution Approach 2:
The patent extracts the harmful function (gas accumulation leading to explosion) from the sealed system by providing dedicated extraction pathways through the vent holes in the electrode lead and lead films. This allows gas to be removed from the sealed environment through controlled channels rather than causing structural failure
3Reliability
If vent holes are added to release pressure, then safety is improved, but device complexity increases due to additional components and structures
Solution Approach 1:
The patent makes the electrode lead and lead films multi-functional by incorporating vent holes directly into these existing components. These components simultaneously serve their primary function of electrical connection and their secondary function of gas venting, eliminating the need for separate venting mechanisms and reducing overall device complexity
Solution Approach 2:
The patent merges the venting function with the existing electrode lead and lead film structures. By combining the electrical connection function and gas venting function in the same components, the design avoids adding separate venting devices, seals, or mechanisms, thereby maintaining simplicity while improving safety
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 discharges gas externally, reducing the risk of explosions and ensuring safer operation of the secondary battery, even under abnormal conditions, by concentrating pressure at the vent holes and maintaining sealing elsewhere.
Implementation Method 1
the second vent holes may overlap the first vent hole to form a path penetrating the lead films and the electrode lead
Data Source
AI summary
A secondary battery is provided. The secondary battery may include an electrode assembly; a pouch including a sealing portion along outer edges thereof and configured to accommodate and seal the electrode assembly; an electrode lead inserted through the sealing portion and connected to the electrode assembly, the electrode lead including a first vent hole opened toward the electrode assembly; and lead films disposed between the electrode lead and the sealing portion of the pouch, the lead films including second vent holes opened toward the electrode assembly. The second vent holes may overlap the first vent hole to form a path penetrating the lead films and the electrode lead.