Multilayer polymer dielectric film

Patent metadata

Field	Value
Publication number	US-10614958-B2
Application number	US-201816118179-A
Country	US
Kind code	B2
Filing date	Aug 30, 2018
Priority date	Oct 16, 2008
Publication date	Apr 7, 2020
Grant date	Apr 7, 2020

Abstract

A multilayer polymer dielectric film includes a stack of coextruded, alternating first dielectric layers and second dielectric layers that receive electrical charge. The first dielectric layers include a first polymer material and the second dielectric layers include a second polymer material different from the first polymer material. The first polymer material has a permittivity greater than the second polymer material. The second polymer material has a breakdown strength greater than the first polymer material. Adjoining first dielectric layers and second dielectric layers define an interface between the layers that delocalizes electrical charge build-up in the layers. The stack has substantially the crystallographic symmetry before and during receiving electrical charge.

First claim

Having describe the invention, the following is claimed:

1. A capacitor comprising:
a stack of coextruded, alternating first dielectric layers and second dielectric layers, the first dielectric layers comprising a first polymer material and the second dielectric layers comprising a second polymer material different from the first polymer material, the first polymer material having a permittivity greater than the second polymer material, and the second polymer material having a breakdown strength greater than the first polymer material, wherein the capacitor stores an electrical charge, wherein adjoining first dielectric layers and second dielectric layers define an interface between the layers that delocalizes charge build-up in the layers, and wherein the first dielectric layers and second dielectric layers have thicknesses of about 5 nm to about 5000 nm.

2. The capacitor of claim 1 , the stack comprising about 4 to about 500,000 alternating first dielectric layers and second dielectric layers.

3. The capacitor of claim 1 , the first dielectric layers and second dielectric layers being fabricated by multilayer coextrusion forced assembly processes.

4. The capacitor of claim 1 , the stack being axially oriented in at least one direction substantially parallel to a surface of the film at a ratio effective to increase the breakdown strength of the film.

5. The capacitor of claim 1 , at least one of the first polymer layers and the second polymer layers further comprising a filler to improve the dielectric properties of the first polymer material and/or the second polymer material.

6. The capacitor of claim 1 , the stack of coextruded first dielectric layers and second dielectric layers having a breakdown voltage that is greater than the breakdown voltage of the first dielectric layers and the breakdown voltage of the second dielectric layers.

7. The capacitor of claim 1 , the stack of coextruded first dielectric layers and second dielectric layers having an electrical conductivity that is greater than the electrical conductivity of the first dielectric layers and the electrical conductivity of the second dielectric layers.

8. The capacitor of claim 1 , the stack of coextruded first dielectric layers and second dielectric layers having an energy density that is greater than the energy density of the first dielectric layers and the energy density of the second dielectric layers.

9. The capacitor of claim 1 , the first dielectric layer comprising PVDF, a copolymer thereof, or a composite thereof and the second dielectric layer comprising at least one of polypropylene (PP), polyethylene terephthalate (PET), polycarbonate (PC), poly(p-phenylene sulfide), copolymers thereof, or composites thereof.

Assignees

• Univ Case Western Reserve
• Us Gov Sec Navy

Inventors

• Baer Eric
• Hiltner Anne
• Shirk James S
• Wolak Mason
• Zhou Zheng
• Mackey Matthew
• Carr Joel

Classifications

• Y10T428/24942

  including components having same physical characteristic in differing degree · CPC title

• B29C48/21

  the layers being joined at their surfaces · CPC title

• B32B2307/518

  bi-axially · CPC title

• H01G4/20

  using combinations of dielectrics from more than one of groups H01G4/02 - H01G4/06 (H01G4/12 takes precedence) · CPC title

• B32B2307/20

  having particular electrical or magnetic properties, e.g. piezoelectric · CPC title