LAMINATED BODY

• US 20170365833A1
• Filed: 06/20/2017
• Published: 12/21/2017
• Est. Priority Date: 06/21/2016
• Status: Active Grant

• Current Assignee: Sumitomo Chemical Company Limited
• Original Assignee: Sumitomo Chemical Company Limited
• Inventors: OGATA, Toshihiko, YOSHIMARU, Chikae, MURAKAMI, Chikara
• Granted Patent: US 10,361,418 B2
• Time in Patent Office: Days
• CPC Class Codes: B05D 1/18 performed by dipping
• CPC Class Codes: B05D 1/42 by non-rotary members
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/0585 of accumulators having only flat construction elements, i.e. flat positive electrodes, flat negative electrodes and flat separators
• CPC Class Codes: H01M 50/417 Polyolefins
• CPC Class Codes: H01M 50/426 Fluorocarbon polymers
• CPC Class Codes: H01M 50/451 comprising layers of only organic material and layers containing inorganic material
• CPC Class Codes: H01M 50/489 Separators, membranes, diaphragms or spacing elements inside the cells, characterised by their physical properties, e.g. swelling degree, hydrophilicity or shut down properties
• CPC Class Codes: H01M 50/491 Porosity
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

To afford a laminated body that is usable as a nonaqueous electrolyte secondary battery separator and that is not easily curled, a laminated body includes: a porous base material containing a polyolefin-based resin as a main component; and a porous layer containing a polyvinylidene fluoride-based resin, the porous base material having a temperature rise ending period of a particular value with respect to the amount of resin per unit area, the polyvinylidene fluoride-based resin containing crystal form α in an amount of not less than 36 mol % with respect to 100 mol % of a total amount of the crystal form α and crystal form β contained in the polyvinylidene fluoride-based resin.

Claims

1. A laminated body, comprising:

a porous base material containing a polyolefin-based resin as a main component; and

a porous layer on at least one surface of the porous base material, the porous layer containing a polyvinylidene fluoride-based resin,

the porous base material having a temperature rise ending period of 2.9 seconds·

m²/g to 5.7 seconds·

m²/g with respect to an amount of resin per unit area in a case where the porous base material has been impregnated with N-methylpyrrolidone containing 3% by weight of water and has then been irradiated with a microwave having a frequency of 2455 Hz and an output of 1800 W,

the polyvinylidene fluoride-based resin containing crystal form α

in an amount of not less than 36 mol % with respect to 100 mol % of a total amount of the crystal form α and

crystal form β

contained in the polyvinylidene fluoride-based resin,

where the amount of the crystal form α

is calculated from an absorption intensity at around 765 cm<sup>−

1</sup> in an IR spectrum of the porous layer, and an amount of the crystal form β

is calculated from an absorption intensity at around 840 cm<sup>−

1</sup> in the IR spectrum of the porous layer.

2. The laminated body according to claim 1,

wherein

the polyvinylidene fluoride-based resin contains (i) a homopolymer of vinylidene fluoride and/or (ii) a copolymer of vinylidene fluoride and at least one monomer selected from the group consisting of hexafluoropropylene, tetrafluoroethylene, trifluoroethylene, trichloroethylene, and vinyl fluoride.

3. The laminated body according to claim 1,

wherein

the polyvinylidene fluoride-based resin has a weight-average molecular weight of not less than 200,000 and not more than 3,000,000.

4. The laminated body according to claim 1,

wherein

the porous layer contains a filler.

5. The laminated body according to claim 4,

wherein

the filler has a volume-average particle size of not less than 0.01 μ

m and not more than 10 μ

m.

6. A nonaqueous electrolyte secondary battery member, comprising:

a cathode;

a laminated body according to claim 1; and

an anode,

the cathode, the laminated body, and the anode being arranged in this order.

7. A nonaqueous electrolyte secondary battery, comprising as a separator a laminated body according to claim 1.