Battery Pack Foam Spacer for Cell Fixation and Expansion Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing elastic members for battery packs face challenges in simultaneously fixing battery cells during contraction and absorbing deformation during expansion, as adjusting the foaming ratio affects the balance between repulsive force and deformation absorption, making it difficult to achieve both effectively.
Innovation Solution
An elastic member made of foam with specific properties, including Asker C hardness between 20 and 40, a foaming ratio of 3.0 to 5.0 times, a closed cell ratio of 50% to 95%, and elliptical bubbles in the cross-section, which allows for optimal hardness and stress reduction, enabling both fixation and deformation absorption.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Force
If the foaming ratio is reduced to increase repulsive force, then the hardness of the foam increases and biasing force improves, but the stress during compression increases making it difficult to compress and deform the elastic member
Solution Approach 1:
The patent applies parameter changes by precisely controlling the foaming ratio within 3.0-5.0 times and Asker C hardness within 20-40 to achieve optimal balance between repulsive force and compressibility. This quantitative parameter optimization resolves the contradiction by finding the sweet spot where the foam is hard enough to provide biasing force but soft enough to be compressible for deformation absorption.
Solution Approach 2:
The patent introduces local quality through the elliptical bubble structure with specific aspect ratios (1.2-3.0), creating non-uniform internal architecture that provides different mechanical properties in different directions and compression stages. The elliptical shape allows the foam to exhibit appropriate stiffness for biasing while maintaining compressibility for deformation absorption.
2Stability of the object's composition
If the foaming ratio is increased to improve deformation absorption, then the hardness of the foam decreases and compressibility improves, but the repulsive force at low compression decreases making fixation insufficient
Solution Approach 1:
The patent resolves this contradiction through parameter changes by setting the foaming ratio to 3.0-5.0 times and Asker C hardness to 20-40, which optimizes the balance between softness for deformation absorption and hardness for providing repulsive force. This quantitative control ensures the foam can both absorb expansion deformation and maintain fixation during contraction.
Solution Approach 2:
The patent employs composite material principles by creating a foam with specific closed cell ratio (50-95%) combined with elliptical bubble structure, resulting in a material that exhibits both energy absorption capability through bubble collapse and structural integrity for maintaining repulsive force.
3Reliability
If the closed cell ratio is increased to improve structural integrity, then the foam becomes harder and more stable, but the ability to compress and deform follows the battery cell expansion worsens
Solution Approach 1:
The patent applies parameter changes by optimizing the closed cell ratio to 50-95%, which provides sufficient structural integrity while maintaining adequate compressibility. This parameter optimization resolves the contradiction by finding the balance point where the foam structure is stable enough for reliability but still flexible enough to follow battery cell deformation.
Solution Approach 2:
The patent introduces dynamics through the elliptical bubble structure that can dynamically adjust its compression behavior. The elliptical shape allows the foam to progressively collapse and deform in response to battery expansion, providing adaptive deformation following capability while maintaining structural integrity through the controlled closed cell 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 elastic member effectively fixes battery cells during contraction and absorbs deformation during expansion, maintaining insulation and performance while being suitable for limited spaces within the battery pack.
Implementation Method 1
an elastic member that may be elastically deformed following the deformation of the battery cells
Implementation Method 2
when the battery cell is discharged (contracted), the elastic member needs to be able to absorb the deformation of the battery cell by compressing and deforming itself
Implementation Method 3
the battery cell is fixed by a biasing force of the elastic member when being charged (expanded)
Data Source
AI summary
An elastic member for battery pack is arranged in a battery pack in which multiple battery cells are arranged side by side in a predetermined direction and is in elastic contact with the battery cells. The elastic member for battery pack (4) is made of a foam that satisfies the following (a) to (d): (a) an Asker C hardness is 20 or more and 40 or less; (b) a foaming ratio is 3.0 times or more and 5.0 times or less; (c) a closed cell ratio is 50% or more and 95% or less; (d) with a direction of elastic contact with a battery cell as a thickness direction, a structure of a bubble in a cross-section in the thickness direction has an elliptical bubble having an elongated elliptical shape in the thickness direction.