Encapsulating material for solar cell and solar cell module

Patent metadata

Field	Value
Publication number	US-9260556-B2
Application number	US-201314377818-A
Country	US
Kind code	B2
Filing date	Feb 7, 2013
Priority date	Feb 10, 2012
Publication date	Feb 16, 2016
Grant date	Feb 16, 2016

Abstract

An encapsulating material for solar cell of the invention contains an ethylene/α-olefin copolymer, an organic peroxide, at least one crosslinking aid selected from a group consisting of divinyl aromatic compounds, cyanurates, diallyl compounds, triallyl compounds, oximes and maleimides, and a (meth)acrylate-based monomer. The content of the (meth)acrylate-based monomer in the encapsulating material for solar cell is in a range of 0.1 parts by weight to 5.0 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer, and the content of the crosslinking aid in the encapsulating material for solar cell is in a range of 0.1 parts by weight to 3 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer.

First claim

The invention claimed is:

1. An encapsulating material for solar cell containing an ethylene/α-olefin copolymer, an organic peroxide, at least one crosslinking aid selected from a group consisting of divinyl aromatic compounds, cyanurates, diallyl compounds, triallyl compounds, oximes and maleimides, a (meth)acrylate-based monomer, and an ethylenic unsaturated silane compound,
wherein a content of the (meth)acrylate-based monomer in the encapsulating material for solar cell is in a range of 0.1 parts by weight to 5.0 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer,
a content of the crosslinking aid in the encapsulating material for solar cell is in a range of 0.1 parts by weight to 3 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer, and
a content of the ethylenic unsaturated silane compound in the encapsulating material for solar cell is in a range of 0.1 parts by weight to 5 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer.

2. The encapsulating material for solar cell according to claim 1 ,
wherein a content of an aluminum element in the ethylene/α-olefin copolymer is in a range of 10 ppm to 500 ppm.

3. The encapsulating material for solar cell according to claim 1 ,
wherein a volume resistivity of an encapsulating layer formed by crosslinking the encapsulating material for solar cell, which is based on JIS K6911 and measured at a temperature of 100° C. with an applied voltage of 500 V, is in a range of 1.0×10 15 Ω·cm to 1.0×10 18 Ω·cm.

4. The encapsulating material for solar cell according to claim 1 ,
wherein a molecular weight of the (meth)acrylate-based monomer is equal to or more than 150.

5. The encapsulating material for solar cell according to claim 1 ,
wherein the ethylene/α-olefin copolymer satisfies the following requirements a1) to a4):
a1) a content ratio of a structural unit derived from ethylene is in a range of 80 mol % to 90 mol %, and a content ratio of a structural unit derived from an α-olefin having 3 to 20 carbon atoms is in a range of 10 mol % to 20 mol %;
a2) MFR, which is based on ASTM D1238 and measured under conditions of a temperature of 190° C. and a load of 2.16 kg, is in a range of 0.1 g/10 minutes to 50 g/10 minutes;
a3) a density, which is measured on the basis of ASTM D1505, is in a range of 0.865 g/cm 3 to 0.884 g/cm 3 ; and
a4) a shore A hardness, which is measured on the basis of ASTM D2240, is in a range of 60 to 85.

6. The encapsulating material for solar cell according to claim 5 ,
wherein MFR of the ethylene/α-olefin copolymer, which is based on ASTM D1238 and measured under conditions of a temperature of 190° C. and a load of 2.16 kg, is in a range of 10 g/10 minutes to 50 g/10 minutes.

7. The encapsulating material for solar cell according to claim 1 ,
wherein a one-minute half-life temperature of the organic peroxide is in a range of 100° C. to 170° C., and
a content of the organic peroxide in the encapsulating material for solar cell is in a range of 0.1 parts by weight to 3.0 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer.

8. The encapsulating material for solar cell according to claim 1 ,
wherein the ethylene/α-olefin copolymer is prepared by using a catalyst for olefin polymerization containing at least one compound selected from a group consisting of metallocene compounds, organic aluminumoxy compounds and organic aluminum compounds.

9. The encapsulating material for solar cell according to claim 1 , further comprising at least one of additives selected from a group consisting of an ultraviolet absorber, a hindered amine-based light stabilizer and a heat-resistant stabilizer
in which a content of the above-described additives in the encapsulating material for solar cell is in a range of 0.005 parts by weight to 5 parts by weight with respect to 100 parts by weight of the ethylene/α-olefin copolymer.

10. The encapsulating material for solar cell according to claim 1 obtained by melting and kneading the ethylene/α-olefin copolymer, the organic peroxide, the (meth)acrylate-based monomer, and the crosslinking aid, and then molding, by extrusion, the mixture into a sheet shape.

11. The encapsulating material for solar cell according to claim 1 having a sheet shape.

12. A solar cell module comprising:
a transparent surface protective member,
a back surface protective member,
a solar cell element, and
an encapsulating layer which is formed by crosslinking the encapsulating material for solar cell according to claim 1 and encapsulates the solar cell element between the transparent surface protective member and the back surface protective member.

Assignees

• Mitsui Chemicals Tohcello Inc

Inventors

• Ikenaga Shigenobu
• Takeuchi Fumito
• Ito Tomoaki

Classifications

• C08L2312/00

  Crosslinking · CPC title

• C08J2351/06

  grafted on to homopolymers or copolymers of aliphatic hydrocarbons containing only one carbon-to-carbon double bond · CPC title

• C08F8/30

  Introducing nitrogen atoms or nitrogen-containing groups · CPC title

• C08K5/00

  Use of organic ingredients · CPC title

• C09D123/0815

  Copolymers of ethene with aliphatic 1-olefins · CPC title