Composite Battery Separator With Embedded Fillers Against Delamination
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Secondary batteries and electric devices face challenges in reliability performance, particularly due to delamination of base films in separators and vulnerability to nail penetration and heat resistance issues.
Innovation Solution
A separator design featuring a porous coating between two porous base films, with filler particles embedded to a depth of at least 1 μm in each film, enhancing the binding force and incorporating a higher melting point for one film to improve heat resistance and puncture resistance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a porous coating is disposed between two porous base films with filler particles embedded to a depth of at least 1 μm, then the binding force between films is improved and heat resistance is enhanced, but the device complexity and manufacturing difficulty increase
Solution Approach 1:
The separator employs a composite structure consisting of two porous base films with different melting points and a porous coating layer containing filler particles. This composite design combines the advantages of multiple materials to achieve both high binding force and heat resistance while managing the complexity through systematic material integration
Solution Approach 2:
The porous coating is selectively applied only in specific regions between the base films, and filler particles are embedded to specific depths (at least 1 μm) in localized areas. This local quality approach enhances binding force and heat resistance where needed without unnecessarily complicating the entire separator structure
2Strength
If the embedding depth of filler particles is increased to at least 1 μm in the porous base film, then the binding force and nail penetration resistance are improved, but the manufacturing precision requirements increase
Solution Approach 1:
The patent specifies a quantitative parameter for filler particle embedding depth (at least 1 μm) to optimize the balance between binding force and manufacturing feasibility. This parameter change transforms a qualitative requirement into a measurable control target, facilitating precise manufacturing while ensuring adequate strength
3Temperature
If a higher melting point material is used for the first porous base film compared to the second porous base film, then heat resistance is improved, but the manufacturing cost and material selection complexity increase
Solution Approach 1:
The first porous base film with higher melting point is strategically positioned and used only where enhanced heat resistance is most critical, while the second porous base film uses a different melting point material. This local quality differentiation optimizes heat resistance performance without requiring all components to use expensive high-temperature materials
Solution Approach 2:
The separator uses a composite of two different porous base films with different melting points, combining materials with optimal properties for their specific functions. This approach balances heat resistance requirements with manufacturing ease by not over-specifying material properties throughout the entire structure
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 improves the reliability and cycle performance of secondary batteries by increasing the binding force between films, enhancing heat resistance, and preventing separator puncture, thus improving overall battery stability.
Implementation Method 1
an embedding depth of at least part of the filler particles in the first porous base film is greater than or equal to 1 μm and/or an embedding depth of at least part of the filler particles in the second porous base film is greater than or equal to 1 μm... the binding force between the porous coating and the first porous base film and/or the second porous base film is effective improved
Implementation Method 2
the heat resistance performance and nail penetration performance of the separator are effectively improved
Implementation Method 3
a first porous base film; a second porous base film; and a porous coating disposed between the first porous base film and the second porous base film
Data Source
AI summary
A separator is provided, comprising a first porous base film, a second porous base film, and a porous coating positioned between the first and second porous base films. The porous coating includes a binder and filler particles. At least a portion of the filler particles is embedded into the first porous base film and/or the second porous base film to a depth of at least 1 μm. The binder facilitates adhesion between the porous coating and the base films. The embedding of filler particles enhances the bonding strength between the porous coating and the base films, which in turn improves the separator's thermal stability and resistance to nail penetration. These improvements contribute to enhanced safety and reliability of the battery incorporating the separator.