Solar Cell Laminate Using Ethylene Copolymer Composite
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current encapsulant materials for solar cell modules, such as EVA, face issues with low elastic modulus, poor rigidity, and insufficient moisture-proofness, leading to handleability problems and reduced power generation efficiency, especially in high-humidity environments.
Innovation Solution
A laminate for solar cells comprising a resin layer with an ethylene/α-olefin random copolymer and an ethylene/α-olefin block copolymer, along with a silane-modified ethylene-based resin, which eliminates the need for a crosslinking step and provides excellent moisture-proofness, transparency, and handleability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Illumination intensity
If EVA is used as encapsulant material, then flexibility and transparency are improved, but moisture-proofness and rigidity deteriorate
Solution Approach 1:
The patent uses a composite material consisting of ethylene/α-olefin copolymer and cyclic olefin resin. The ethylene/α-olefin copolymer provides flexibility and adhesion similar to EVA, while the cyclic olefin resin contributes excellent moisture barrier properties and rigidity. This composite approach allows the encapsulant to simultaneously achieve good transparency, flexibility, and moisture-proofness without relying on crosslinking agents.
2Temperature
If crosslinking is performed with organic peroxide to improve heat resistance, then heat resistance is improved, but circuit corrosion and interlayer delamination occur
Solution Approach 1:
The patent removes the harmful crosslinking step involving organic peroxides from the encapsulant formulation. Instead, it achieves heat resistance through the inherent thermal stability of the ethylene/α-olefin copolymer and cyclic olefin resin combination, along with controlled gel fraction (5-60%), eliminating the source of acetic acid generation that causes circuit corrosion and interlayer delamination.
Solution Approach 2:
The patent changes the chemical composition parameters by using ethylene/α-olefin copolymer with specific gel fraction (5-60%) combined with cyclic olefin resin. This parameter adjustment provides heat resistance without requiring crosslinking agents, thereby preventing the harmful effects of organic peroxide decomposition while maintaining thermal stability.
3Ease of manufacture
If EVA sheet is used for sealing, then ease of manufacture is improved, but handleability and rigidity deteriorate
Solution Approach 1:
The patent formulates a composite encapsulant material combining ethylene/α-olefin copolymer and cyclic olefin resin that maintains the ease of sealing characteristics of EVA sheets while significantly improving rigidity and handleability. The composite structure provides sufficient structural support for handling during module assembly while retaining the sealing performance needed for encapsulation.
4Reliability
If high-density polyethylene is used to improve moisture-proofness, then moisture-proofness is improved, but transparency and flexibility deteriorate
Solution Approach 1:
The patent combines ethylene/α-olefin copolymer with cyclic olefin resin in specific proportions to achieve a balance between moisture barrier properties and optical characteristics. The cyclic olefin resin provides excellent moisture resistance, while the ethylene/α-olefin copolymer maintains flexibility and good transparency, avoiding the excessive rigidity and poor transparency issues of high-density polyethylene.
Data Source
AI summary
Provided are a laminate for solar cells, which facilitates production of solar cell modules, which does not require a crosslinking step and which is excellent in transparency, moisture-proofness, sealability and handleability (rigidity), and a solar cell module produced by the use of the laminate. The laminate for solar cells has a resin layer (I)-1 or a resin layer (I)-2 as at least one outermost layer thereof, and has a resin layer (II) that contains an etylene-based polymer (C) satisfying a specific requirement and a nucleating agent (D). The resin layer (I)-1 is a resin layer containing an ethylene/α-olefin random copolymer (A) satisfying a specific requirement, and an ethylene/α-olefin block copolymer (B) satisfying a specific requirement. The resin layer (I)-2 is a resin layer containing a silane-modified etylene-based resin (X).