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CN-117451221-B - Flexible force electric coupling sensor and preparation method thereof

CN117451221BCN 117451221 BCN117451221 BCN 117451221BCN-117451221-B

Abstract

The invention discloses a flexible force electric coupling sensor and a preparation method thereof. The electric energy storage device comprises a first electret layer, a first insulating layer, a core electrode, a second insulating layer and a second electret layer which are sequentially stacked, wherein an induction electrode is arranged, permanent charges are stored in the first electret layer and the second electret layer, the first electret layer and the second electret layer are symmetrically distributed by taking the core electrode as a symmetrical surface, when deformation occurs, potential difference or current can be formed between the induction electrode and the core electrode, and concave-convex structures are arranged at the interfaces of the first electret layer and the second electret layer. According to the flexible force electric coupling sensor and the preparation method thereof, the concave-convex structure is arranged on the opposite surface of the double-layer electret layer in the symmetrical sensor structure, so that the field plate area is increased, the electric charge is concentrated at the convex part, the change amplitude of the electric potential or the electric field during deformation is enhanced, the open-circuit voltage or the short-circuit electric charge quantity is further increased, and the sensitivity of the flexible force electric coupling sensor is remarkably improved.

Inventors

  • Xiaozhang Yingyi
  • BAO YIWEN

Assignees

  • 上海大宫新材料有限公司

Dates

Publication Date
20260505
Application Date
20231024

Claims (10)

  1. 1. The flexible force electric coupling sensor is characterized by comprising a first electret layer, a first insulating layer, a core electrode, a second insulating layer and a second electret layer which are sequentially laminated, wherein an induction electrode is arranged on at least one side of the first electret layer, which is away from the core electrode; Permanent charges are stored in the first electret layer and the second electret layer, the polarity directions and the shapes of the first electret layer and the second electret layer are symmetrically distributed by taking the core electrode as a symmetrical surface, and when the flexible force electric coupling sensor is deformed by applying external force, potential difference or current can be formed between the induction electrode and the core electrode; A first interface of the first electret layer contacted with the first insulating layer and a second interface of the second electret layer contacted with the second insulating layer are both provided with concave-convex structures, The preparation method of the flexible force electric coupling sensor comprises the following steps of, Carrying out corona polarization treatment on the polymer film to obtain a polarized film, carrying out baking aging treatment on the polarized film to obtain a first electret layer and a second electret layer, Providing a continuous polymer film, and etching the surface of the polymer film to form a concave-convex structure; And forming a non-perpendicular included angle between the electric field direction and the surface of the polymer film with the concave-convex structure when the corona polarization treatment is performed, so that charges formed by the corona polarization treatment have a tendency to concentrate towards the edges of the convex parts of the concave-convex structure.
  2. 2. The flexible force electrically coupled sensor of claim 1, wherein the concave-convex structure is symmetrically distributed with the core electrode as a symmetry plane.
  3. 3. The flexible force electrically coupled sensor of claim 2, wherein the relief structure comprises periodically repeating raised portions and recessed portions, and wherein edges of the raised portions are prismatic, wherein the raised portions have a width of 0.001-2mm, wherein the recessed portions have a width of 0.001-2mm, and wherein a height difference between the raised portions and the recessed portions is 1/10-1/2 of a thickness of the first electret layer or the second electret layer.
  4. 4. A flexible force electrically coupled sensor according to claim 3, wherein the permanent charge has a tendency to concentrate towards the edge of the boss.
  5. 5. A flexible force electrically coupled sensor according to claim 3, wherein the first electret layer and the second electret layer have a thickness of 1-300 μm; the first electret layer and the second electret layer are made of high-resistivity dielectrics and comprise any one or more than two of HDPE, PP, PVDF.
  6. 6. The flexible force electrically coupled sensor of claim 1, further comprising a first waterproof layer covering a side of the first electret layer facing away from the core electrode and a second waterproof layer covering a side of the second electret layer facing away from the core electrode; the induction electrode is arranged in the first waterproof layer or is in electrical contact with the first waterproof layer.
  7. 7. The flexible force electrically coupled sensor of claim 6, further comprising a first shielding layer covering the first waterproof layer and a second shielding layer covering the second waterproof layer and a shielding electrode; the shielding electrode is electrically connected with the second shielding layer.
  8. 8. A method of manufacturing a flexible force transducer as claimed in any one of claims 1 to 7, comprising: And sequentially attaching and forming a laminated structure of the first electret layer, the first insulating layer, the core electrode, the second insulating layer and the second electret layer, and correspondingly arranging the induction electrode to obtain the flexible force electric coupling sensor.
  9. 9. The method of claim 8, wherein the corona polarization treatment has a voltage of + -5-15 kV and a temperature of 15-35 ℃; the baking aging treatment is carried out at 80-100deg.C for 20-40min.
  10. 10. The method according to claim 8, wherein, The electric field direction forms a non-perpendicular angle with the surface of the polymer film having the concave-convex structure in the range of 60-80 deg.

Description

Flexible force electric coupling sensor and preparation method thereof Technical Field The invention relates to the technical field of sensing devices, in particular to a flexible force electric coupling sensor and a preparation method thereof. Background The statements in this section merely provide background information related to the present disclosure and may not constitute prior art. The intelligent networking (AIOT) formed by the deep fusion of 5G, artificial Intelligence (AI) and internet of things (IOT) connects human society and physical systems into an organic whole that affects various aspects of daily life in the future. The total amount of devices that access IOT globally by 2025 would reach 750 billion as predicted by the prospective industry institute, 5-fold increase in decades. Future intelligent health care, intelligent home, intelligent transportation, etc. are in great demand for various sensors. The electret piezoelectric film is an important type in the force-electricity coupling sensor, the sensitivity of the traditional PVDF piezoelectric film sensor is low, and the traditional PVDF piezoelectric film sensor needs to be provided with a large gain in practical application, so that the manufacturing cost is increased, and the traditional PVDF piezoelectric film sensor is greatly limited in acoustic application occasions with high sensitivity requirements such as intelligent health medical treatment, intelligent home and intelligent transportation. The piezoelectric electret film sensor has high sensitivity, and can be well applied to the application fields. Some prior art uses double layers of electret films connected in series or in parallel to improve the sensitivity of an electret film sensor, for example, chinese patent No. CN 102522495A provides a method for improving the signal-to-noise ratio of a piezoelectric electret film sensor, which adopts a lamination method to laminate the piezoelectric electret films in series or in parallel, so as to doubly improve the charge and voltage output of the piezoelectric electret film sensor, so as to improve the sensitivity. However, the sensitivity of the electret film sensor in the prior art still is difficult to meet the requirements of smart health medical treatment, smart home and intelligent traffic high-sensitivity application. It should be noted that the foregoing description of the background art is only for the purpose of providing a clear and complete description of the technical solution of the present invention and is presented for the convenience of understanding by those skilled in the art. The above-described solutions are not considered to be known to the person skilled in the art simply because they are set forth in the background of the invention section. Disclosure of Invention The invention aims to provide a flexible force electric coupling sensor and a preparation method thereof, which further improve the sensitivity of an electret film force electric sensor. In order to solve the technical problems, in a first aspect, the invention provides a flexible force electric coupling sensor, which comprises a first electret layer, a first insulating layer, a core electrode, a second insulating layer and a second electret layer which are sequentially stacked, wherein an induction electrode is arranged on one side of the first electret layer, which is opposite to the core electrode, permanent charges are stored in the first electret layer and the second electret layer, the polarity directions and the shapes of the first electret layer and the second electret layer are symmetrically distributed by taking the core electrode as a symmetrical plane, when the flexible force electric coupling sensor is deformed by applying external force, potential difference or current can be formed between the induction electrode and the core electrode, and a concave-convex structure is arranged on a first interface of the first electret layer, which is in contact with the first insulating layer, and a second interface of the second electret layer, which is in contact with the second insulating layer. According to the technical scheme, the electret layers symmetrically arranged on the two sides of the core electrode are utilized to strengthen the electric field intensity at the core electrode, when the flexible force electric coupling sensor deforms due to pressure, both the open circuit voltage and the short circuit charge quantity between the core electrode and the induction electrode are improved, and the concave-convex structure is specially arranged at the opposite interface of the two electret layers, so that the effective area of the field plate is improved, and a certain tip charge concentration effect is achieved on the other hand, the change of the electric potential is more obvious when the flexible force electric coupling sensor deforms, and the sensitivity of the flexible force electric coupling sensor is remarkably improved. Further, t