METHOD FOR MANUFACTURING PIEZOELECTRIC TEXTILE ENERGY HARVESTER AND SENSOR

Abstract

Energy harvesting device comprising: a first layer (1) of electrically conductive textile fabric material; a second layer (2) of electrically conductive textile fabric material; a layer of piezoelectric polymer film (3) arranged between the first (1) and the second (2) electrically conductive textile layers; wherein the piezoelectric polymer film layer (3) is laminated between the first (1) and second (2) electrically conductive textile layer.

Claims

1. An energy harvesting device comprising: a first layer of electrically conductive textile fabric material, a second layer of electrically conductive textile fabric material, a layer of piezoelectric polymer film arranged between the first and the second electrically conductive textile layers, wherein the piezoelectric polymer film layer is laminated between the first and second electrically conductive textile layer.

2. The energy harvesting device according to claim 1, wherein the layer of piezoelectric polymer film is polarized.

3. The energy harvesting device according to claim 1, wherein the piezoelectric polymer film layer is plasma treated.

4. The energy harvesting device according to claim 1, wherein the first and second electrically conductive textile layers comprise any 2D or 3D fabric made of natural fiber or synthetic fiber with a woven, knitted, embroidered or non-woven structure.

5. The energy harvesting device according to claim 4, wherein the natural or synthetic material of the first and second electrically conductive textile layers is coated with conductive material, wherein the coating is selected from metallic and/or carbon and/or polymeric conductive material.

6. The energy harvesting device according to claim 1, wherein the layer of piezoelectric polymer film comprises material with piezoelectric properties, wherein the material comprises a polarized polyvinylidenefluoride (PVDF) film and/or a modified polarized PVDF film.

7. The energy harvesting device according to claim 6, wherein the piezoelectric material of the piezoelectric polymer film layer is coated with conductive layers based on metal or conductive polymer.

8. A sensor comprising an energy harvesting device according to claim 1.

9. A method for manufacturing an energy harvesting device and sensor comprising the steps of preparing a first electrically conductive textile layer and a second electrically conductive textile layer by either coating a textile or nonwoven with a conductive material or producing a knitted or embroidery structure with a conductive thread, activating a piezoelectric polymer film layer with plasma, laminating the piezoelectric polymer film layer between the first and second electrically conductive layers and integrating a rectifying circuit in the device.

10. The method according to claim 9, wherein the temperature in the lamination process of the piezoelectric polymer film layer between the first and second electrically conductive textile layers is in the range of 70° C. to 190° C., wherein the pressure in the lamination process is in the range of 1 N to 40 N, wherein the energy input is in the range of 0.5 kW to 3 kW.

11. The method according to claim 9, wherein the piezoelectric polymer film layer is polarized before the lamination process.

12. The method according to claim 9, wherein the activation is done with a low pressure plasma, wherein it is activated with oxygen containing functional groups using a mixture of argon and molecular oxygen at a ratio of 1 to 4.

13. The energy harvesting device according to claim 5, wherein the coating is selected from silver, carbon, or poly(3,4-ethylenedioxythiophene) polystyrene sulfonate (PEDOT:PSS).

14. The energy harvesting device according to claim 7, wherein the metal or conductive polymer includes carbon, silver, or poly(3,4-ethylenedioxythiophene) polystyrene sulfonate.

15. The method according to claim 9, wherein the temperature in the lamination process of the piezoelectric polymer film layer between the first and second electrically conductive textile layers is in the range of 80° C. to 170° C., wherein the pressure in the lamination process is in the range of 30 N to 40 N, wherein the energy input is in the range of 1 kW to 2 kW.

16. The method according to claim 12, wherein the pressure of the plasma is in the range of 0.1 mbar to 0.5 mbar.

17. The method according to claim 12, wherein the exposure time is in the range of 30 s to 600 s.

Description

[0028] The foregoing and other objects, features and advantages of the invention will become more apparent from the following detailed description, which proceeds with reference to the accompanying figures.

[0029] FIG. 1 shows the three layers of the inventive composite piezoelectric textile with an oscilloscope measuring the generated voltages.

[0030] FIG. 2 shows the layers of the inventive piezoelectric textile including conductive coatings on both sides of the piezoelectric layer.

[0031] FIG. 1 depicts the textile based piezoelectric energy harvesting device and sensor comprises a first layer 1 of electrically conductive textile fabric material, a second layer 2 of electrically conductive textile fabric material and a layer of piezoelectric polymer film 3 laminated between the first 1 and the second 2 electrically conductive textile layers.

[0032] The piezoelectric polymer film layer 3 may have conductive layers 4, 5 at each side as shown in FIG. 2. After coating the piezoelectric polymer film layer 3 with the conductive layers 4, 5 it may be laminated between the first 1 and second 2 electrically conductive textile layers.

[0033] An important advantage of the inventive energy harvester is that any conductive material can be used for the conductive layers 4, 5. The textile material may be a weaved, knitted, embroidery or nonwoven structure. One can use these various structures due to the fact that the piezoelectric polymer film layer 3 is laminated between the conductive layers 4, 5. Furthermore, the lamination step simplifies the production of the energy harvester.

[0034] In order to enhance adhesion of the layers in the lamination process, the surface of the layer of piezoelectric polymer film 3 is activated beforehand. The surface activation is done by a low-pressure plasma treatment.

[0035] A big advantage of the so produced energy harvester is that is washable and very durable. Thus, it can be easily integrated into clothing to generate energy from human movement. This is especially effective if it is integrated into sports clothing. Moreover, these energy generating textiles may also be used in the context of smart-textiles and textiles used for healthcare, where the generated electrical power may be used immediately.

[0036] The inventive self-powering sensors can find their applications also in the transport sector including transport on water, on roads and in the air. In all these applications the important properties of the inventive energy harvester namely flexibility, wearability, washability and comfortability are mandatory. At the same time the energy harvester is very effective in producing energy out of external energy from the ambient environment due to the strong coupling between the piezoelectric polymer film layer and the conductive textile layers. This strong coupling is achieved via the above described plasma treatment of the piezoelectric layer and the subsequent lamination process of the piezoelectric layer with the conductive layers.