Bi-Layer Solar Cell Encapsulant Adhesion and Shock Absorption
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current solar cell encapsulant materials face challenges such as low adhesion to solar cell laminate layers, creep resistance issues, and limited weatherability and light stability, particularly with ethylene acrylate ester copolymers, which require additional primers and cross-linking for effective bonding, and higher modulus ionomers that compromise shock absorbance.
Innovation Solution
A thermoplastic bi-layer film or sheet comprising a first surface layer of an acid copolymer or ionomer and a second surface layer of an ethylene acrylate ester copolymer, with specific weight percentages of polymerized residues and neutralization of carboxylic acids with metallic ions, providing enhanced adhesion and flexibility without the need for adhesion primers.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Strength
If ethylene acrylate ester copolymers are used as encapsulant material, then shock absorbance is improved, but adhesion to solar cell laminate layers deteriorates
Solution Approach 1:
The patent uses a composite structure consisting of an ethylene acrylate ester copolymer layer (providing shock absorbance) combined with an adhesion promoter layer containing silane coupling agents (providing adhesion). This composite material approach allows both requirements to be satisfied simultaneously by combining materials with complementary properties.
Solution Approach 2:
The patent introduces an intermediary substance (adhesion promoter containing silane coupling agents) between the ethylene acrylate ester copolymer and the solar cell laminate layers. This intermediary mediates the bonding interface, enabling the low-modulus material to achieve adequate adhesion without compromising its shock absorbance properties.
2Reliability
If cross-linking agents are added to improve adhesion, then adhesion to solar cell laminate layers is improved, but device complexity increases
Solution Approach 1:
The patent combines the adhesion promoter functionality with the encapsulant material itself by incorporating silane coupling agents directly into the ethylene acrylate ester copolymer matrix. This merging eliminates the need for separate adhesion promoter applications and cross-linking processes, thereby improving adhesion while reducing manufacturing complexity.
Solution Approach 2:
The ethylene acrylate ester copolymer with incorporated silane coupling agents provides self-adhesion capability during the lamination process. The material serves its own adhesion function through the in-situ formation of silane bonds with the solar cell laminate layers, eliminating the need for external adhesion promoters or complex cross-linking procedures.
3Stability of the object's composition
If higher modulus ionomers are used, then structural stability is improved, but shock absorbance deteriorates
Solution Approach 1:
The patent employs a composite approach by combining the low-modulus ethylene acrylate ester copolymer (providing shock absorbance) with structural support layers such as glass substrates and metal backings. This composite structure achieves overall structural stability while maintaining the shock absorbance properties of the polymer encapsulant.
Solution Approach 2:
The patent applies different mechanical properties to different regions of the solar cell structure. The ethylene acrylate ester copolymer encapsulant provides local shock absorbance at the cell level, while the overall module structure achieves structural stability through the combination of multiple layers with complementary mechanical properties.
Data Source
AI summary
The present invention provides a pre-formed bi-layer thermoplastic film or sheet comprising a first surface layer made of acid copolymers, or ionomers, or combinations thereof and a second surface layer made of ethylene acrylate ester copolymers, a solar cell pre-laminate assembly comprising the same, and a simplified process for manufacturing a solar cell module derived therefrom.