Self-powered pressure sensor, method of manufacturing the same and pressure sensing module

Abstract

The application discloses a self-powered pressure sensor, a preparation method thereof and a pressure sensing module, and relates to the technical field of sensors.The self-powered pressure sensor comprises a first electrode assembly and a first hydrogel assembly.The first electrode assembly comprises a first electrode and a second electrode, and the first electrode and the second electrode are arranged at intervals along a first direction.A first accommodating space is arranged between the first electrode and the second electrode, and the first accommodating space comprises a plurality of subspaces, each of which is telescopic along the first direction.The first hydrogel assembly is arranged in the first accommodating space, and the first hydrogel assembly comprises a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer.The proportion of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each subspace is not completely the same.When different subspaces are compressed by an action force of the same size, the current output by an external circuit connected with the first electrode and the second electrode is also not completely the same.Different output currents correspond to different subspaces, so that the position under pressure can be deduced.

Description

Technical Field

[0001] This invention relates to the field of self-powered pressure sensor technology, and in particular to a self-powered pressure sensor, its fabrication method, and a pressure sensing module. Background Technology

[0002] In recent years, hydrogels based on natural polymers have been widely used in various flexible wearable devices, such as flexible self-powered pressure sensors, due to their high safety, high biocompatibility, low cost, and tunable electrical and mechanical properties.

[0003] Integrating flexible energy storage devices and flexible self-powered pressure sensors into a single unit creates a self-powered flexible self-powered pressure sensor with both energy storage and pressure monitoring functions, eliminating the need for an external non-flexible power source. While hydrogel-based self-powered pressure sensors have been reported in the literature, a single flexible self-powered pressure sensor cannot distinguish pressure at different locations, limiting its applicability.

[0004] Therefore, it is necessary to provide a new self-powered pressure sensor, its fabrication method, and pressure sensing module to solve or at least alleviate the aforementioned technical defects. Summary of the Invention

[0005] The main objective of this invention is to provide a self-powered pressure sensor, its preparation method, and a pressure sensing module, aiming to solve the technical problem that existing self-powered pressure sensors cannot determine the location of the pressure area.

[0006] To achieve the above objectives, the present invention provides a self-powered pressure sensor, the self-powered pressure sensor comprising:

[0007] A first electrode assembly, comprising a first electrode and a second electrode, wherein the first electrode and the second electrode are spaced apart along a first direction, and a first accommodating space is provided between the first electrode and the second electrode, wherein the first accommodating space comprises a plurality of subspaces, and each subspace extends or retracts along the first direction.

[0008] A first hydrogel component is disposed in the first accommodating space. The first hydrogel component includes a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer. The proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each of the sub-spaces are not exactly the same.

[0009] In one embodiment, the first accommodating space includes a first subspace, a second subspace, and a third subspace arranged along a second direction perpendicular to the first direction; the first pressure-sensitive conductive hydrogel layer includes a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer; the first hydrogel electrolyte layer includes a first electrolyte layer and a second electrolyte layer; the first subspace is filled with the first pressure-sensitive conductive layer; the second subspace is filled with the second pressure-sensitive conductive layer and the first electrolyte layer arranged sequentially along the first direction; and the third subspace is filled with the second electrolyte layer.

[0010] In one embodiment, the self-powered pressure sensor further includes a second electrode assembly and a second hydrogel assembly. The second hydrogel assembly includes a second pressure-sensitive conductive hydrogel layer and a second hydrogel electrolyte layer. The second pressure-sensitive conductive hydrogel layer includes a third pressure-sensitive conductive layer and a fourth pressure-sensitive conductive layer. The second hydrogel electrolyte layer includes a third electrolyte layer and a fourth electrolyte layer. The second electrode assembly includes a third electrode and a fourth electrode spaced apart along the first direction. A second accommodating space is provided between the third electrode and the fourth electrode. The second accommodating space includes a fourth subspace, a fifth subspace, and a sixth subspace arranged along the second direction. The fourth subspace is filled with the third electrolyte layer. The fifth subspace is filled with the fourth electrolyte layer and the third pressure-sensitive conductive layer arranged sequentially along the first direction. The sixth subspace is filled with the fourth pressure-sensitive conductive layer. The fourth subspace and the third subspace are staggered along the second direction.

[0011] In one embodiment, the first electrode assembly and the second electrode assembly are connected in series, the third electrode and the second electrode have opposite polarities and are attached together, and the sixth subspace and the first subspace are staggered along the second direction; the self-powered pressure sensor further includes an external electrode assembly, the external electrode assembly includes a first external electrode and a second external electrode spaced apart along the first direction, the first external electrode is electrically connected to the first electrode, the second external electrode is electrically connected to the fourth electrode, and the self-powered pressure sensor further includes a fifth pressure-sensitive conductive layer, the space between the first external electrode and the second external electrode is filled with the fifth pressure-sensitive conductive layer.

[0012] In one embodiment, the first electrode assembly further includes a fifth electrode, the second electrode and the fifth electrode are spaced apart along the first direction, the second electrode includes a first body and a first extension connected to each other, a first receiving space is formed between the first body and the first electrode, the fifth electrode includes a second body and a second extension connected to each other, the second body and the first electrode are disposed opposite to each other on both sides of the first body; the first hydrogel assembly further includes a sixth pressure-sensitive conductive layer and a fifth electrolyte layer, the sixth pressure-sensitive conductive layer is filled between the second body and the first body, and the fifth electrolyte layer is filled between the first extension and the second extension.

[0013] In one embodiment, a plurality of the subspaces are arranged sequentially along a second direction perpendicular to the first direction, the content of the first hydrogel electrolyte layer in each subspace decreases sequentially along the second direction, and the content of the first pressure-sensitive conductive hydrogel layer in each subspace increases sequentially along the second direction.

[0014] In one embodiment, the first hydrogel assembly further includes a sixth electrolyte layer, and the self-powered pressure sensor further includes a third hydrogel assembly and a fourth hydrogel assembly. The third hydrogel assembly includes a third pressure-sensitive conductive hydrogel layer, a third hydrogel electrolyte layer, and a seventh electrolyte layer. The fourth hydrogel assembly includes a fourth pressure-sensitive conductive hydrogel layer and a fourth hydrogel electrolyte layer. A first electrolytic cavity is further provided between the first electrode and the second electrode. The first electrolytic cavity and the first accommodating space are arranged along the second direction, and the first electrolytic cavity is filled with the sixth electrolyte layer. The first electrode assembly further includes a sixth electrode and a seventh electrode. The sixth electrode and the second electrode are disposed opposite to each other on both sides of the first electrode, and a second accommodating space is formed between the sixth electrode and the first electrode. The accommodating space includes a accommodating cavity and a second electrolytic cavity arranged sequentially along a third direction. Both the first and second directions are perpendicular to the third direction. The accommodating cavity is filled with the third pressure-sensitive conductive hydrogel layer and the third hydrogel electrolyte layer. The content of the third pressure-sensitive conductive hydrogel layer in the accommodating cavity decreases sequentially along the third direction, and the content of the third hydrogel electrolyte layer in the accommodating cavity increases sequentially along the third direction. The second electrolytic cavity is filled with the seventh electrolyte layer. The seventh electrode and the first electrode are disposed opposite each other on both sides of the second electrode. A third accommodating space is formed between the seventh electrode and the second electrode. The fourth pressure-sensitive conductive hydrogel layer and the fourth hydrogel electrolyte layer are sequentially disposed in the third accommodating space along the second direction or the third direction.

[0015] In one embodiment, the plurality of subspaces include a first subspace, a second subspace, and a third subspace. The second subspace is arranged around the periphery of the first subspace, and the third subspace is arranged around the periphery of the second subspace. One of the first subspace, the second subspace, and the third subspace is filled with the pressure-sensitive conductive hydrogel layer, another is filled with the hydrogel electrolyte layer, and the remaining subspace is filled with the pressure-sensitive conductive hydrogel layer and the hydrogel electrolyte layer arranged sequentially along the first direction.

[0016] In addition, the present invention also provides a pressure sensing module, the pressure sensing module comprising a plurality of self-powered pressure sensors as described in any one of claims 1 to 8, wherein the plurality of self-powered pressure sensors are arranged sequentially along the transverse and / or longitudinal direction; or, the plurality of self-powered pressure sensors are arranged sequentially along the center outward direction.

[0017] Furthermore, the present invention also provides a method for fabricating a self-powered pressure sensor. The self-powered pressure sensor includes a first electrode assembly, which includes a first electrode and a second electrode. The first electrode and the second electrode are spaced apart along a first direction, and a first accommodating space is provided between the first electrode and the second electrode. The first accommodating space includes a plurality of subspaces, each of which expands and contracts along the first direction. A first hydrogel assembly is disposed in the first accommodating space. The first hydrogel assembly includes a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer. The proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each of the subspaces are not completely the same. The method for fabricating the self-powered pressure sensor includes the following steps:

[0018] (1) Preparation of the first pressure-sensitive conductive hydrogel layer

[0019] 2g of polyvinyl alcohol and 10ml of deionized water were mixed and stirred at 100°C until the polyvinyl alcohol was completely dissolved to obtain a polyvinyl alcohol solution; 0.2g of xanthan gum, 0.15g of carbon nanotubes and 10mL of glycerol were mixed into a homogeneous solution to obtain a mixed solution; the polyvinyl alcohol solution and the mixed solution were mixed, and the mixed solution was transferred to a -40°C constant temperature oven and allowed to stand for 12h to obtain the first pressure-sensitive conductive hydrogel layer;

[0020] (2) Preparation of the first hydrogel electrolyte layer

[0021] 0.48g chitosan, 0.48g sodium alginate and 4ml glycerol were stirred evenly to obtain a mixture; the mixture was heated at 90°C for 30 minutes; the mixture was then allowed to stand and cool at room temperature for 24 hours to obtain a hydrogel; the hydrogel was immersed in 2M ZnSO4 + 0.1M MnSO4 electrolyte for 4 hours to obtain the first hydrogel electrolyte layer;

[0022] (3) The first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer are disposed in the first accommodating space to obtain the self-powered pressure sensor.

[0023] In the above technical solution of the present invention, the first electrode and the second electrode are spaced apart, and the accommodating space formed between the first electrode and the second electrode is divided into several subspaces. Each subspace is filled with a first pressure-sensitive conductive hydrogel layer, or a first hydrogel electrolyte layer, or both a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer. In the subspace filled with the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer, the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer are arranged along a first direction. The first electrode, the second electrode, and the first hydrogel assembly constitute a battery that can output current to an external circuit. The characteristic of the first pressure-sensitive conductive hydrogel layer is that its resistance decreases when pressed. Since the proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each subspace are not exactly the same, the current in the external circuit connected to the first electrode and the second electrode is not exactly the same when different subspaces are compressed with the same force. Different output currents correspond to different subspaces. Based on the output current, it can be determined which subspace is compressed, thereby determining the location of the compression. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 This is a schematic diagram of the structure of a self-powered pressure sensor according to an embodiment of the present invention;

[0026] Figure 2 This is a schematic diagram of the structure of a self-powered pressure sensor according to an embodiment of the present invention;

[0027] Figure 3 This is a schematic diagram of the structure of a self-powered pressure sensor according to an embodiment of the present invention;

[0028] Figure 4 This is a partial structural schematic diagram of a self-powered pressure sensor according to an embodiment of the present invention;

[0029] Figure 5 This is a partial structural schematic diagram of a self-powered pressure sensor according to an embodiment of the present invention;

[0030] Figure 6 This is a partial structural schematic diagram of a self-powered pressure sensor according to an embodiment of the present invention;

[0031] Figure 7 for Figure 6 Left view of the self-powered pressure sensor shown;

[0032] Figure 8 This is a partial structural schematic diagram of a self-powered pressure sensor according to an embodiment of the present invention;

[0033] Figure 9 for Figure 1 The graph shows the relationship between the changing current / initial current (ΔI / I0) and time in the external circuit of the self-powered pressure sensor.

[0034] Figure 10 for Figure 1 The graph shows the relationship between the changing current / initial current (ΔI / I0) and time in the external circuit of the self-powered pressure sensor.

[0035] Figure 11 This is a partial cross-sectional view of a pressure sensing module according to an embodiment of the present invention;

[0036] Figure 12 This is a partial cross-sectional view of a pressure sensing module according to an embodiment of the present invention;

[0037] Figure 13 This is a schematic flowchart of a method for preparing a self-powered pressure sensor according to an embodiment of the present invention.

[0038] Explanation of icon numbers:

[0039]

[0040]

[0041] The realization of the objective, functional characteristics and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0042] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0043] It should be noted that all directional indications (such as up, down, forward, backward, left, and right) in the embodiments of this invention are only used to interpret a specific posture (as shown in the attached diagram). Figure 6 and Figure 7 The relative positions and movements of the components shown below are considered. If the specific posture changes, the directional indication will also change accordingly.

[0044] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined with "first" or "second" can explicitly or implicitly include at least one of that feature.

[0045] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are implemented by those skilled in the art. When the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0046] This invention provides a self-powered pressure sensor 1, in one embodiment, as follows: Figures 1 to 8 As shown, the self-powered pressure sensor 1 includes a first electrode assembly 11 and a first hydrogel assembly 12. The first electrode assembly 11 includes a first electrode 111 and a second electrode 112, which are spaced apart along a first direction. A first accommodating space 113 is provided between the first electrode 111 and the second electrode 112. The first accommodating space 113 includes multiple subspaces 1131, each of which extends and retracts along the first direction. The first hydrogel assembly 12 is disposed in the first accommodating space 113 and includes a first pressure-sensitive conductive hydrogel layer 121 and a first hydrogel electrolyte layer 122. The proportions of the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122 in each subspace 1131 are not exactly the same.

[0047] The first electrode 111 and the second electrode 112 are spaced apart. The first accommodating space 113 formed between the first electrode 111 and the second electrode 112 is divided into several subspaces 1131. These subspaces 1131 can be arranged along a certain direction or in a lattice configuration. Each subspace 1131 is filled with a first pressure-sensitive conductive hydrogel layer 121, or a first hydrogel electrolyte layer 122, or both. Within the subspace 1131 filled with the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122, the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122 are arranged along a first direction. Figure 6 The diagram shows the vertical direction. The first electrode 111, the second electrode 112, and the first hydrogel assembly 12 constitute the battery, which can output current to an external circuit. The first pressure-sensitive conductive hydrogel layer 121 has the characteristic that its resistance decreases when pressed. Because the proportions of the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122 in each sub-space 1131 are not exactly the same, the current to the external circuit connected to the first electrode 111 and the second electrode 112 is not exactly the same when different sub-spaces 1131 are compressed with the same force. Different current magnitudes correspond to different sub-spaces 1131. By determining which sub-space 1131 is compressed based on the current magnitude, the location of the compression can be determined. It should be noted that compressing the sub-space 1131 can be done by pressing the first electrode 111 with the same force, or by pressing the second electrode 112 with the same force.

[0048] According to an embodiment of the present invention, a membrane layer is provided between the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122, thereby preventing the electrolyte of the first hydrogel electrolyte from deforming and seeping into the first pressure-sensitive conductive hydrogel layer 121 due to repeated pressing.

[0049] In addition, such as Figure 1 As shown, in one embodiment, the first accommodating space 113 includes a first subspace 1131a, a second subspace 1131b, and a third subspace 1131c arranged along a second direction perpendicular to the first direction, wherein the second direction is... Figure 6As shown in the left-right direction, the first pressure-sensitive conductive hydrogel layer 121 includes a first pressure-sensitive conductive layer 1211 and a second pressure-sensitive conductive layer 1212, the first hydrogel electrolyte layer 122 includes a first electrolyte layer 1221 and a second electrolyte layer 1222, the first subspace 1131a is filled with the first pressure-sensitive conductive layer 1211, the second subspace 1131b is filled with the second pressure-sensitive conductive layer 1212 and the first electrolyte layer 1221 arranged sequentially along the first direction, and the third subspace 1131c is filled with the second electrolyte layer 1222. The first subspace 1131a is filled with a first pressure-sensitive conductive layer 1211. When the first subspace 1131a is subjected to pressure, the resistance of the first pressure-sensitive conductive layer 1211 within the first subspace 1131a decreases, which is equivalent to an approximate short circuit inside the battery. Therefore, the current in the external circuit connected to the first electrode 111 and the second electrode 112 decreases. The second subspace 1131b is filled with a second pressure-sensitive conductive layer 1212 and a first electrolyte layer 1221. When the second subspace 1131b is subjected to pressure, the resistance of the second pressure-sensitive conductive layer 1212 decreases, and the first electrolyte layer 1221 becomes conductive. Therefore, the current in the external circuit connected to the first electrode 111 and the second electrode 112 decreases. The current in the external circuit connected to the second electrode 112 increases. The third subspace 1131c is filled with the second electrolyte layer 1222. When the third subspace 1131c is under pressure, the interface capacitance between the second electrolyte layer 1222 and the first electrode 111, as well as the interface capacitance between the second electrode 112 and the second electrode 112, is disturbed. Therefore, the current in the external circuit connected to the first electrode 111 and the second electrode 112 will only change slightly. Thus, the location of the pressure area—whether it increases, decreases, or changes slightly—can be determined by observing whether the current in the external circuit increases, decreases, or changes slightly. It should be noted that the external circuit can be connected to a detection device to detect changes in current. The detection device can be an ammeter 3. By observing the change in the pointer of the ammeter 3, the change in current can be obtained, thereby determining the location of the pressure. Alternatively, the detection device can be a light source, such as an LED lamp. By observing the change in the brightness of the LED lamp, the change in power supply can be obtained, thereby determining the location of the pressure area.

[0050] It should also be noted that if the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122 are arranged sequentially along the first direction, and the multiple sub-spaces 1131 are arranged sequentially along the second direction, and the content of the first pressure-sensitive conductive hydrogel layer 121 and the first hydrogel electrolyte layer 122 in each sub-space 1131 is the same, let the change in the external circuit current of the first electrode 111 and the second electrode 112 be denoted as ΔI, and let the initial current value of the external circuit current of the first electrode 111 and the second electrode 112 be denoted as I0, then if the second sub-space 1131b is pressed, the change of the ratio of ΔI to I0 over time is as follows: Figure 9As shown. If the first subspace 1131a is pressed, the ratio of its ΔI to I0 changes with time as follows. Figure 10 As shown by the solid line in the figure, if the third subspace 1131c is pressed, the ratio of ΔI to I0 changes with time as follows: Figure 10 As shown by the dashed line in the image.

[0051] In addition, such as Figure 2As shown, in one embodiment, the self-powered pressure sensor 1 further includes a second electrode assembly 13 and a second hydrogel assembly 14. The second hydrogel assembly 14 includes a second pressure-sensitive conductive hydrogel layer 141 and a second hydrogel electrolyte layer 142. The second pressure-sensitive conductive hydrogel layer 141 includes a third pressure-sensitive conductive layer 1411 and a fourth pressure-sensitive conductive layer 1412, and the second hydrogel electrolyte layer 142 includes a third electrolyte layer 1421 and a fourth electrolyte layer 1422. The first electrode assembly 11 and the second electrode assembly 13 are connected in parallel. The second electrode assembly 13 includes a third electrode 131 and a fourth electrode 1422 spaced apart along a first direction. A second accommodating space 133 is provided between electrode 132, third electrode 131 and fourth electrode 132. The second accommodating space 133 includes a fourth subspace 1333, a fifth subspace 1334 and a sixth subspace 1335 arranged along a second direction. The fourth subspace 1333 is filled with a third electrolyte layer 1421. The fifth subspace 1334 is filled with a fourth electrolyte layer 1422 and a third varistor conductive layer 1411 arranged sequentially along a first direction. The sixth subspace 1335 is filled with a fourth varistor conductive layer 1412. The fourth subspace 1333 and the third subspace 1331 are arranged in a staggered manner along the second direction.The addition of the second electrode assembly 13 and the second hydrogel assembly 14 is to address the issue that when the current in the external circuit fluctuates only slightly, relying solely on the first electrode assembly 11 and the first hydrogel assembly 12 is insufficient to determine whether a large pressure is applied to the third subspace 1131c or a small pressure to the first subspace 1131a or the second subspace 1131b. Determining the pressing position using the first electrode assembly 11 and the first hydrogel assembly assumes that the pressing force is large. Therefore, this embodiment distinguishes between the two by adding the second electrode assembly 13 and the second hydrogel assembly 14. Taking the fourth subspace 1333 located below the first subspace 1131a, the fifth subspace 1334 located below the second subspace 1131b, and the sixth subspace 1335 located below the third subspace 1131c as examples, when a large pressure is applied to the first electrode 111 above the third subspace 1131c, the current fluctuation of the first battery composed of the first electrode assembly 11 and the first hydrogel assembly 12... Although the pressure is relatively small, the sixth subspace 1335, located below the third subspace 1131c, is also compressed by the pressure, causing a significant drop in the current output of the second battery composed of the second electrode assembly 13 and the second hydrogel assembly 14. When the first electrode 111 above the first subspace 1131a is pressed with a smaller pressure, the current output of the first battery decreases slightly, and the current output of the second battery fluctuates less, indicating that the pressure is acting on the first subspace 1131a. When the second electrode 112 above the second subspace 1131b is pressed with a smaller pressure, the current output of the first battery increases slightly, and the current output of the second battery also increases slightly, indicating that the pressure is acting on the second subspace 1131b. Therefore, by adding the second electrode assembly 13 and the second hydrogel assembly 14, it is possible to distinguish whether a large pressure is acting on the third subspace 1131c or a small pressure is acting on the first subspace 1131a or the second subspace 1131b, thereby improving the recognition accuracy of the self-powered pressure sensor 1. It should be noted that as long as the third subspace 1131c and the fourth subspace 1333 are staggered along the second direction, the positions of the fifth subspace 1334 and the sixth subspace 1335 can be arbitrarily interchanged after the position of the fourth subspace 1333 is determined. Taking the above embodiment as an example, the fourth subspace 1333 is below the first subspace 1131a, and the fifth subspace 1334 can be below the second subspace 1131b or below the third subspace 1131c.

[0052] According to one embodiment of the present invention, the second electrode 112 and the third electrode 131 can be a common electrode, that is, a first receiving space 113 is formed between the first electrode 111 and the common electrode, and a second receiving space 133 is formed between the fourth electrode 132 and the common electrode. By using a common electrode, the number of electrodes used is reduced, the cost of the self-powered pressure sensor 1 is reduced, and the integration of the self-powered pressure sensor 1 is improved.

[0053] In one embodiment, such as Figure 3As shown, the self-powered pressure sensor 1 also includes a second electrode assembly 13 and a second hydrogel assembly 14. The second hydrogel assembly 14 includes a second pressure-sensitive conductive hydrogel layer 141 and a second hydrogel electrolyte layer 142. The second pressure-sensitive conductive hydrogel layer 141 includes a third pressure-sensitive conductive layer 1411 and a fourth pressure-sensitive conductive layer 1412. The second hydrogel electrolyte layer 142 includes a third electrolyte layer 1421 and a fourth electrolyte layer 1422. The first electrode assembly 11 and the second electrode assembly 13 are connected in series. The second electrode assembly 13 includes a third electrode 131 and a fourth electrode 132 spaced apart along a first direction. The third electrode 131 and the second electrode 132 have opposite polarities and are attached to each other. A second receiving space 133 is provided between the third electrode 131 and the fourth electrode 132. The second receiving space 133 includes a fourth subspace 1333 and a fifth subspace 1333 arranged along a second direction. Subspaces 1334 and 1335 are further divided into subspaces 1334 and 1335. Subspace 1333 is filled with a third electrolyte layer 1421. Subspace 1334 is filled with a fourth electrolyte layer 1422 and a third pressure-sensitive conductive layer 1411 arranged sequentially along a first direction. Subspace 1335 is filled with a fourth pressure-sensitive conductive layer 1412. Subspace 1335 and subspace 1131a are staggered along a second direction. The self-powered pressure sensor 1 also includes an external electrode assembly 15. The external electrode assembly 15 includes a first external electrode 151 and a second external electrode 152 spaced apart along a first direction. The first external electrode 151 is electrically connected to the first electrode 111. The second external electrode 152 is electrically connected to the fourth electrode 132. The self-powered pressure sensor 1 also includes a fifth pressure-sensitive conductive layer 16. The space between the first external electrode 151 and the second external electrode 152 is filled with the fifth pressure-sensitive conductive layer 16.This embodiment can also be used to distinguish whether a large pressure is applied to the third subspace 1131c or a small pressure is applied to the first subspace 1131a or the second subspace 1131b. Taking the fourth subspace 1333 located below the first subspace 1131a, the fifth subspace 1334 located below the second subspace 1131b, and the sixth subspace 1335 located below the third subspace 1131c as an example, when the first electrode 111 above the third subspace 1131c is pressed with a larger pressure, the current fluctuation amplitude of the first battery composed of the first electrode assembly 11 and the first hydrogel assembly 12 is smaller, but the current fluctuation amplitude of the first battery composed of the first electrode assembly 11 and the first hydrogel assembly 12 is smaller. The sixth subspace 1335 below subspace 1131c is also subjected to this pressure, causing a significant decrease in the current output of the second battery composed of the second electrode assembly 13 and the second hydrogel assembly 14. When the first electrode 111 above the first subspace 1131a is pressed with a smaller pressure, the current output of the first battery decreases slightly, and the current output of the second battery fluctuates less, indicating that the pressure is acting on the first subspace 1131a. When the second electrode 112 above the second subspace 1131b is pressed with a smaller pressure, the current output of the first battery increases slightly, and the current output of the second battery also increases slightly, indicating that the pressure is acting on the first subspace 1131a. The pressure is determined to be acting on the second subspace 1131b. Furthermore, this embodiment also includes an external electrode assembly 15. When the first external electrode 151 or the second external electrode 152 is pressed, it is equivalent to a short circuit occurring in the battery formed by the first external electrode 151, the second external electrode 152, and the fifth pressure-sensitive conductive layer 16, resulting in excessive current and excessive voltage division within the battery's internal resistance. This leads to a decrease in the battery's output voltage, causing a decrease in the branch current connected in parallel with the battery. Since the first external electrode 151 is connected to the first electrode 111, and the second external electrode 152 is connected to the fourth electrode 132, the first electrode assembly 11 and the second electrode assembly 13... The series circuit is connected in parallel with the battery composed of the first peripheral electrode 151, the second peripheral electrode 152 and the fifth pressure-sensitive conductive layer 16. Therefore, pressing the first peripheral electrode 151 or the second peripheral electrode 152 will cause the external circuits of the first electrode assembly 11 and the second electrode assembly 13 to drop. This allows it to be determined whether the pressing position is located in the first subspace 1131a, the second subspace 1131b, the third subspace 1131c or the location of the peripheral electrode assembly 15. Thus, without adding any additional materials, the pressure position can be distinguished, improving the detection range and detection accuracy of the self-powered pressure sensor 1.

[0054] Additionally, in one embodiment, such as Figure 4As shown, the first electrode assembly 11 further includes a fifth electrode 114. The second electrode 112 and the fifth electrode 114 are spaced apart along a first direction. The second electrode 112 includes a first body 1121 and a first extension 1122 connected to each other. A first receiving space 113 is formed between the first body 1121 and the first electrode 111. The fifth electrode 114 includes a second body 1141 and a second extension 1142 connected to each other. The second body 1141 and the first electrode 111 are disposed opposite to each other on both sides of the first body 1121. The first hydrogel assembly 12 further includes a sixth pressure-sensitive conductive layer 123 and a fifth electrolyte layer 124. The space between the second body 1141 and the first body 1121 is filled with the sixth pressure-sensitive conductive layer 123, and the space between the first extension 1122 and the second extension 1142 is filled with the fifth electrolyte layer 124. The first electrode 111, the second electrode 112, and the first hydrogel component 12 form the first battery, and the second electrode 112, the fifth electrode 114, the sixth pressure-sensitive conductive layer 123, and the fifth electrolyte layer 124 form the third battery. The first and third batteries are connected in parallel. This embodiment can also be used to distinguish whether a large pressure is applied to the third subspace 1131c or a small pressure is applied to the first subspace 1131a or the second subspace 1131b. When a large pressure is applied to the third subspace 1131c, the output current of the first battery fluctuates less, and the output current of the third battery drops significantly. When a small pressure is applied to the first subspace 1131a, the output current of the first battery drops slightly, and the output current of the third battery drops slightly. When a small pressure is applied to the second subspace 1131b, the output current of the first battery rises slightly, and the output current of the third battery drops slightly. In this way, the location of the pressure can be determined, improving the detection accuracy of the self-powered pressure sensor 1.

[0055] In one embodiment, such as Figure 5 As shown, multiple subspaces are arranged sequentially along a second direction perpendicular to the first direction. The content of the first hydrogel electrolyte layer 122 in each subspace decreases sequentially along the second direction, while the content of the first pressure-sensitive conductive hydrogel layer 121 in each subspace increases sequentially along the second direction. Since the content of the first hydrogel electrolyte layer 122 and the first pressure-sensitive conductive hydrogel layer 121 are different in each subspace, the output current of the first battery changes differently when different subspaces are pressed with the same pressure, thus determining the pressing position.

[0056] Furthermore, in one embodiment, as Figure 6 and Figure 7As shown, the first hydrogel assembly 12 further includes a sixth electrolyte layer 125, and the self-powered pressure sensor 1 further includes a third hydrogel assembly 17 and a fourth hydrogel assembly 18. The third hydrogel assembly 17 includes a third pressure-sensitive conductive hydrogel layer 171, a third hydrogel electrolyte layer 172, and a seventh electrolyte layer 173. The fourth hydrogel assembly 18 includes a fourth pressure-sensitive conductive hydrogel layer 181 and a fourth hydrogel electrolyte layer 182. A first electrolytic cavity 117 is also provided between the first electrode 111 and the second electrode 112. The first electrolytic cavity 117 and the first accommodating space 113 are arranged along the second direction, and the first electrolytic cavity 117 is filled with the sixth electrolyte layer 125. The first electrode assembly 11 further includes a sixth electrode 115 and a seventh electrode 116. The sixth electrode 115 and the second electrode 112 are disposed opposite each other on both sides of the first electrode 111, and a second electrode 116 is formed between the sixth electrode 115 and the first electrode 111. The second receiving space 133 includes a receiving cavity 1331 and a second electrolysis cavity 1332 arranged sequentially along a third direction. Both the first and second directions are perpendicular to the third direction. The receiving cavity 1331 is filled with a third pressure-sensitive conductive hydrogel layer 171 and a third hydrogel electrolyte layer 172. The content of the third pressure-sensitive conductive hydrogel layer 171 in the receiving cavity 1331 decreases sequentially along the third direction, while the content of the third hydrogel electrolyte layer 172 in the receiving cavity 1331 increases sequentially along the third direction. The second electrolysis cavity 1332 is filled with a seventh electrolyte layer 173. A seventh electrode 116 and a first electrode 111 are disposed opposite each other on both sides of a second electrode 112. A third receiving space is formed between the seventh electrode 116 and the second electrode 112. A fourth pressure-sensitive conductive hydrogel layer 181 and a fourth hydrogel electrolyte layer 182 are sequentially arranged in the third receiving space along either the second or third direction. The third direction is... Figure 7In the front-to-back direction shown, the content of the third pressure-sensitive conductive hydrogel layer 171 in the second accommodating space 133 decreases sequentially, while the content of the third hydrogel electrolyte layer 172 increases sequentially. This causes the sixth electrode 115 to be pressed at any position along the third direction with the same pressure, resulting in different current rise amplitudes in the external circuits connected to the sixth electrode 115 and the first electrode 111, thus obtaining the position information of the pressed position in the third direction. If the third direction is denoted as the y-direction, then this is equivalent to obtaining the y-axis coordinate information of the pressed position. If the pressure is applied to the electrode above the second electrolytic chamber 1332, since the second electrolytic chamber 1332 is filled with the seventh electrolyte layer 173, it will cause the current rise amplitude to be different from that of the first electrode 115. The external circuit current connected to the sixth electrode 115 and the first electrode 111 experiences slight fluctuations, thus indicating that the pressing position is located in the second electrolytic chamber 1332. When the pressing pressure is transmitted to the first accommodating space 113, since the content of the first hydrogel electrolyte layer 122 in the first accommodating space 113 decreases sequentially along the second direction, while the content of the first pressure-sensitive conductive hydrogel layer 121 increases sequentially along the second direction, this causes the force transmitted from the sixth electrode 115 to the first electrode 111 through the third hydrogel component 17 to change along the second direction if the magnitude of the force remains constant. This will cause the current in the external circuit connected to the first electrode 111 and the second electrode 112 to fluctuate. The corresponding rise in current can be used to obtain the position information of the pressure point in the second direction. If the transmitted pressure acts on the first electrode 111 above the first electrolytic chamber 117, then since the first electrolytic chamber 117 is filled with the sixth electrolyte layer 125, the current in the external circuit connected to the first electrode 111 and the second electrode 112 will fluctuate slightly. Therefore, the current change in the external circuit connected to the sixth electrode 115 and the first electrode 111 can be used to determine whether the pressing position is above the first accommodating space 113 or above the first electrolytic chamber 117. If it is above the first accommodating space 113, the position information of the pressure point in the second direction can also be obtained based on the magnitude of the current rise. The amplitude corresponds to the position information of the pressing position in the second direction; if the second direction is denoted as x-direction, then this is equivalent to obtaining the x-axis coordinate information of the pressing position; if the pressure acts on the area where the first receiving cavity 1331 and the second receiving cavity 1331 overlap in the first direction, then combined with the above y-axis coordinate information, taking the upper surface of the sixth electrode 115 as the xoy plane, the position coordinate of the pressed position on the upper surface of the sixth electrode 115 can be accurately obtained, and thus the pressed position can be known; that is, the pressing position can be obtained based on the current change of the external circuit of the sixth electrode 115 and the first electrode 111 combined with the current change of the external circuit of the first electrode 111 and the second electrode 112.Furthermore, this embodiment also includes a third accommodating space located below the first accommodating space 113. This third accommodating space is filled with a fourth pressure-sensitive conductive hydrogel layer 181 and a fourth hydrogel electrolyte layer 182 to differentiate the magnitude of the pressure applied. Taking the fourth pressure-sensitive conductive hydrogel layer 181 and the fourth hydrogel electrolyte layer 182 arranged sequentially along the second direction as an example, if a small pressure is applied to the sixth electrode 115 located above the area where the fourth pressure-sensitive conductive hydrogel layer and the second accommodating space 133 overlap along the first direction, then the external electrical current of the sixth electrode 115 and the first electrode 111... The external circuits of the second electrode 112 and the seventh electrode 116 rise slightly, while the external circuits of the first electrode 111 and the second electrode 112 drop slightly. If a large pressure is applied to the sixth electrode 115, located above the overlapping area of ​​the fourth pressure-sensitive conductive hydrogel and the second electrolytic chamber 1332 along the first direction, the external circuits of the sixth electrode 115 and the first electrode 111 fluctuate slightly, while the external circuits of the second electrode 112 and the seventh electrode 116 drop significantly, thus distinguishing the magnitude of the force. It should be noted that the fourth pressure-sensitive conductive hydrogel layer 181 is correspondingly disposed below the first receiving space 113. It should also be noted that if the fourth pressure-sensitive conductive hydrogel layer 181 and the fourth hydrogel electrolyte layer 182 are sequentially disposed along a third direction, then the fourth pressure-sensitive conductive hydrogel layer 181 is disposed corresponding to the second receiving space 133.

[0057] In one embodiment, such as Figure 8As shown, the multiple subspaces include a first subspace 1131a, a second subspace 1131b, and a third subspace 1131c. The first pressure-sensitive conductive hydrogel layer 121 includes a first pressure-sensitive conductive layer 1211 and a second pressure-sensitive conductive layer 1212. The first hydrogel electrolyte layer 122 includes a first electrolyte layer 1221 and a second electrolyte layer 1222. The second subspace 1131b is arranged around the first subspace 1131a, and the third subspace 1131c is arranged around the second subspace 1131b. One of the first subspace 1131a, the second subspace 1131b, and the third subspace 1131c is filled with the first pressure-sensitive conductive layer 1211, another is filled with the first electrolyte layer 1221, and the remaining one is filled with the second pressure-sensitive conductive layer 1212 and the second electrolyte layer 1222 arranged sequentially along the first direction. The first subspace 1131a is filled with a first pressure-sensitive conductive layer 1211, the second subspace 1131b is filled with a second pressure-sensitive conductive layer 1212 and a second electrolyte layer 1222 arranged sequentially along a first direction, and the third subspace 1131c is filled with the first electrolyte layer 1221. When the first subspace 1131a is subjected to pressure, the resistance of the first pressure-sensitive conductive layer 1211 located in the first subspace 1131a decreases, which is equivalent to an approximate short circuit inside the battery. Therefore, the current of the external circuit connected to the first electrode 111 and the second electrode 112 decreases. The second subspace 1131b is filled with the second pressure-sensitive conductive layer 1212 and the second electrolyte layer 1222. When the second subspace 1131b is subjected to pressure, the resistance of the second pressure-sensitive conductive layer 1212 decreases. When the resistance of 12 decreases, the second electrolyte layer 1222 becomes conductive, which causes the current in the external circuit connected to the first electrode 111 and the second electrode 112 to increase. The third subspace 1131c is filled with the first electrolyte layer 1221. When the third subspace 1131c is subjected to pressure, the interface capacitance between the first electrolyte layer 1221 and the first electrode 111 and the interface capacitance between the second electrode 112 are disturbed. Therefore, the current in the external circuit connected to the first electrode 111 and the second electrode 112 will only change slightly. Thus, the location of the pressure area in the first subspace 1131a, the second subspace 1131b, or the third subspace 1131c can be determined by whether the current in the external circuit increases, decreases, or changes slightly.According to another embodiment of the present invention, a third electrode assembly and a fifth hydrogel assembly are further disposed below the second electrode 112. The third electrode assembly includes an eighth electrode and a ninth electrode spaced apart along a first direction. A seventh subspace, an eighth subspace, and a ninth subspace are formed between the eighth electrode and the ninth electrode. The seventh subspace is disposed corresponding to the first subspace 1131a. The eighth subspace surrounds the seventh subspace, and the ninth subspace surrounds the eighth subspace. The fifth hydrogel assembly includes a fifth pressure-sensitive conductive hydrogel layer and a fifth hydrogel electrolyte layer. The fifth pressure-sensitive conductive hydrogel layer includes a seventh pressure-sensitive conductive layer and an eighth pressure-sensitive conductive layer. The fifth hydrogel electrolyte layer includes an eighth electrolyte layer and a ninth electrolyte layer. The first electrode assembly can be connected in parallel or in series with the third electrode assembly. Taking the seventh subspace being filled with the eighth electrolyte layer as an example, the eighth subspace is sequentially disposed with the ninth electrolyte layer and the seventh pressure-sensitive conductive layer along the first direction. The ninth subspace is filled with the eighth pressure-sensitive conductive layer. By adding the third electrode assembly and the fifth hydrogel assembly, the pressure position can be determined by observing the current change of the external circuit. The specific principle can be referred to. Figure 2 The corresponding embodiments will not be described in detail here. According to another embodiment of the present invention, a tenth electrode is further disposed below the second electrode 112. The tenth electrode and the second electrode 112 are spaced apart along a first direction. A ninth pressure-sensitive conductive layer is disposed in the overlapping area of ​​the tenth electrode and the first electrode. The remaining space between the tenth electrode and the second electrode is filled with a tenth electrolyte layer. By adding the tenth electrode, the ninth pressure-sensitive conductive layer, and the tenth electrolyte layer, the self-powered pressure sensor 1 can also determine the force location. The specific determination principle can be referred to... Figure 4 The corresponding implementation examples will not be described in detail here.

[0058] Furthermore, the present invention also provides a pressure sensing module 2, in one embodiment, such as... Figure 11 and Figure 12As shown, the pressure sensing module 2 includes multiple electrically connected self-powered pressure sensors 1, arranged sequentially along the horizontal and / or vertical direction; or, arranged sequentially from the center outwards. Since the pressure sensing module 2 employs all the technical solutions of the above embodiments, it possesses at least all the beneficial effects brought about by the technical solutions of the above embodiments, which will not be elaborated further here. By arranging multiple self-powered pressure sensors 1 horizontally, or vertically, or in a matrix arrangement, or arranged sequentially from a certain point outwards, if a self-powered pressure sensor 1 is subjected to force, the electrical signal output by that self-powered pressure sensor 1 will change. Based on the location of the self-powered pressure sensor 1 where the electrical signal changes, the approximate pressing position can be obtained. Then, based on the changes in the output current of each battery within the self-powered pressure sensor 1, the pressed position and whether the pressure is high or low can be determined. The determination principle is the same as in all the above embodiments, and will not be elaborated further here. According to an embodiment of the present invention, the first accommodating space 113 of each power supply pressure sensor 1 includes a first subspace 1131a, a second subspace 1131b and a third subspace 1131c. One of the first subspace 1131a, the second subspace 1131b and the third subspace 1131c is filled with a first pressure-sensitive conductive layer 1211, another is filled with a first electrolyte layer 1221 and the remaining one is filled with a second pressure-sensitive conductive layer 1212 and a second electrolyte layer 1222 arranged sequentially along a first direction.

[0059] Furthermore, this invention also provides a method for fabricating a self-powered pressure sensor, referring to... Figure 13 The schematic diagram shown illustrates the fabrication method of a self-powered pressure sensor. The self-powered pressure sensor includes a first electrode assembly comprising a first electrode and a second electrode, which are spaced apart along a first direction. A first accommodating space is provided between the first and second electrodes, and this first accommodating space includes multiple sub-spaces, each of which expands and contracts along the first direction. A first hydrogel assembly is disposed within the first accommodating space, and the first hydrogel assembly includes a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer. The proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each of the sub-spaces are not entirely the same. The fabrication method of the self-powered pressure sensor includes the following steps:

[0060] S100, Preparation of the first pressure-sensitive conductive hydrogel layer

[0061] 2g of polyvinyl alcohol and 10ml of deionized water were mixed and stirred at 100°C until the polyvinyl alcohol was completely dissolved to obtain a polyvinyl alcohol solution; 0.2g of xanthan gum, 0.15g of carbon nanotubes and 10mL of glycerol were mixed into a homogeneous solution to obtain a mixed solution; the polyvinyl alcohol solution and the mixed solution were mixed, and the mixed solution was transferred to a -40°C constant temperature oven and allowed to stand for 12h to obtain the first pressure-sensitive conductive hydrogel layer;

[0062] S200, Preparation of the first hydrogel electrolyte layer

[0063] 0.48g chitosan, 0.48g sodium alginate and 4ml glycerol were stirred evenly to obtain a mixture; the mixture was heated at 90°C for 30 minutes; the mixture was then allowed to stand and cool at room temperature for 24 hours to obtain a hydrogel; the hydrogel was immersed in 2M ZnSO4 + 0.1M MnSO4 electrolyte for 4 hours to obtain the first hydrogel electrolyte layer;

[0064] S300, the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer are disposed in the first accommodating space to obtain the self-powered pressure sensor.

[0065] The battery comprises a first electrode and a second electrode spaced apart, with the space between them divided into several subspaces. These subspaces can be arranged along a certain direction or in a matrix pattern. Each subspace is filled with a first pressure-sensitive conductive hydrogel layer, a first hydrogel electrolyte layer, or both. In the subspace filled with both the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer, the two layers are arranged along a first direction. The first electrode, the second electrode, and the first hydrogel assembly constitute a battery capable of outputting current to an external circuit. The first pressure-sensitive conductive hydrogel layer has a characteristic that its resistance decreases when pressed. Since the proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each subspace are not exactly the same, the current to the external circuit connected to the first and second electrodes will not be exactly the same when different subspaces are compressed by the same force. Different output currents correspond to different subspaces. By determining which subspace is compressed based on the output current, the location of the compression can be identified.

[0066] The above are merely preferred embodiments of the present invention and do not limit the patent scope of the present invention. Any equivalent structural transformations made under the concept of the present invention using the contents of the specification and drawings of the present invention, or direct / indirect applications in other related technical fields, are included within the patent protection scope of the present invention.

Claims

1. A self-powered pressure sensor, characterized in that, include: A first electrode assembly, comprising a first electrode and a second electrode, wherein the first electrode and the second electrode are spaced apart along a first direction, and a first accommodating space is provided between the first electrode and the second electrode, wherein the first accommodating space comprises a plurality of subspaces, and each subspace extends or retracts along the first direction. A first hydrogel component is disposed in the first accommodating space. The first hydrogel component includes a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer. The proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each of the sub-spaces are not exactly the same.

2. The self-powered pressure sensor according to claim 1, characterized in that, The first accommodating space includes a first subspace, a second subspace, and a third subspace arranged along a second direction perpendicular to the first direction. The first pressure-sensitive conductive hydrogel layer includes a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer. The first hydrogel electrolyte layer includes a first electrolyte layer and a second electrolyte layer. The first subspace is filled with the first pressure-sensitive conductive layer. The second subspace is filled with the second pressure-sensitive conductive layer and the first electrolyte layer arranged sequentially along the first direction. The third subspace is filled with the second electrolyte layer.

3. The self-powered pressure sensor according to claim 2, characterized in that, The self-powered pressure sensor further includes a second electrode assembly and a second hydrogel assembly. The second hydrogel assembly includes a second pressure-sensitive conductive hydrogel layer and a second hydrogel electrolyte layer. The second pressure-sensitive conductive hydrogel layer includes a third pressure-sensitive conductive layer and a fourth pressure-sensitive conductive layer. The second hydrogel electrolyte layer includes a third electrolyte layer and a fourth electrolyte layer. The second electrode assembly includes a third electrode and a fourth electrode spaced apart along the first direction. A second accommodating space is provided between the third electrode and the fourth electrode. The second accommodating space includes a fourth subspace, a fifth subspace, and a sixth subspace arranged along the second direction. The fourth subspace is filled with the third electrolyte layer. The fifth subspace is filled with the fourth electrolyte layer and the third pressure-sensitive conductive layer arranged sequentially along the first direction. The sixth subspace is filled with the fourth pressure-sensitive conductive layer. The fourth subspace and the third subspace are staggered along the second direction.

4. The self-powered pressure sensor according to claim 3, characterized in that, The first electrode assembly and the second electrode assembly are connected in series. The third electrode and the second electrode have opposite polarities and are attached together. The sixth subspace and the first subspace are staggered along the second direction. The self-powered pressure sensor also includes an external electrode assembly, which includes a first external electrode and a second external electrode spaced apart along the first direction. The first external electrode is electrically connected to the first electrode, and the second external electrode is electrically connected to the fourth electrode. The self-powered pressure sensor also includes a fifth pressure-sensitive conductive layer, which fills the space between the first external electrode and the second external electrode.

5. The self-powered pressure sensor according to claim 2, characterized in that, The first electrode assembly further includes a fifth electrode, and the second electrode and the fifth electrode are spaced apart along the first direction. The second electrode includes a first body and a first extension that are connected to each other. A first accommodating space is formed between the first body and the first electrode. The fifth electrode includes a second body and a second extension that are connected to each other. The second body and the first electrode are disposed opposite to each other on both sides of the first body. The first hydrogel assembly further includes a sixth pressure-sensitive conductive layer and a fifth electrolyte layer. The sixth pressure-sensitive conductive layer is filled between the second body and the first body, and the fifth electrolyte layer is filled between the first extension and the second extension.

6. The self-powered pressure sensor according to claim 1, characterized in that, The multiple subspaces are arranged sequentially along a second direction perpendicular to the first direction. The content of the first hydrogel electrolyte layer in each subspace decreases sequentially along the second direction, and the content of the first pressure-sensitive conductive hydrogel layer in each subspace increases sequentially along the second direction.

7. The self-powered pressure sensor according to claim 6, characterized in that, The first hydrogel assembly further includes a sixth electrolyte layer. The self-powered pressure sensor further includes a third hydrogel assembly and a fourth hydrogel assembly. The third hydrogel assembly includes a third pressure-sensitive conductive hydrogel layer, a third hydrogel electrolyte layer, and a seventh electrolyte layer. The fourth hydrogel assembly includes a fourth pressure-sensitive conductive hydrogel layer and a fourth hydrogel electrolyte layer. A first electrolytic cavity is also provided between the first electrode and the second electrode. The first electrolytic cavity and the first accommodating space are arranged along the second direction, and the first electrolytic cavity is filled with the sixth electrolyte layer. The first electrode assembly further includes a sixth electrode and a seventh electrode. The sixth electrode and the second electrode are disposed opposite each other on both sides of the first electrode. A second accommodating space is formed between the sixth electrode and the first electrode. The device includes a receiving cavity and a second electrolysis cavity arranged sequentially along a third direction. Both the first and second directions are perpendicular to the third direction. The receiving cavity is filled with the third pressure-sensitive conductive hydrogel layer and the third hydrogel electrolyte layer. The content of the third pressure-sensitive conductive hydrogel layer in the receiving cavity decreases sequentially along the third direction, and the content of the third hydrogel electrolyte layer in the receiving cavity increases sequentially along the third direction. The second electrolysis cavity is filled with the seventh electrolyte layer. The seventh electrode and the first electrode are disposed opposite each other on both sides of the second electrode. A third receiving space is formed between the seventh electrode and the second electrode. The fourth pressure-sensitive conductive hydrogel layer and the fourth hydrogel electrolyte layer are sequentially disposed in the third receiving space along the second direction or the third direction.

8. The self-powered pressure sensor according to claim 1, characterized in that, The plurality of subspaces include a first subspace, a second subspace, and a third subspace. The first pressure-sensitive conductive hydrogel layer includes a first pressure-sensitive conductive layer and a second pressure-sensitive conductive layer. The first hydrogel electrolyte layer includes a first electrolyte layer and a second electrolyte layer. The second subspace is arranged around the periphery of the first subspace. The third subspace is arranged around the periphery of the second subspace. One of the first subspace, the second subspace, and the third subspace is filled with the first pressure-sensitive conductive layer, another is filled with the first electrolyte layer, and the remaining one is filled with the second pressure-sensitive conductive layer and the second electrolyte layer arranged sequentially along the first direction.

9. A pressure sensing module, characterized in that, The pressure sensing module includes a plurality of self-powered pressure sensors as described in any one of claims 1 to 8, wherein the plurality of self-powered pressure sensors are arranged sequentially along the transverse and / or longitudinal direction; or, the plurality of self-powered pressure sensors are arranged sequentially from the center outward.

10. A method for fabricating a self-powered pressure sensor, characterized in that, The self-powered pressure sensor includes a first electrode assembly, which includes a first electrode and a second electrode. The first electrode and the second electrode are spaced apart along a first direction, and a first accommodating space is provided between the first electrode and the second electrode. The first accommodating space includes multiple subspaces, each of which expands and contracts along the first direction. A first hydrogel assembly is disposed in the first accommodating space. The first hydrogel assembly includes a first pressure-sensitive conductive hydrogel layer and a first hydrogel electrolyte layer. The proportions of the first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer in each of the subspaces are not entirely the same. The fabrication method of the self-powered pressure sensor includes the following steps: (1) Preparation of the first pressure-sensitive conductive hydrogel layer 2g of polyvinyl alcohol and 10ml of deionized water were mixed and stirred at 100°C until the polyvinyl alcohol was completely dissolved to obtain a polyvinyl alcohol solution; 0.2g of xanthan gum, 0.15g of carbon nanotubes and 10mL of glycerol were mixed into a homogeneous solution to obtain a mixed solution; the polyvinyl alcohol solution and the mixed solution were mixed, and the mixed solution was transferred to a -40°C constant temperature oven and allowed to stand for 12h to obtain the first pressure-sensitive conductive hydrogel layer; (2) Preparation of the first hydrogel electrolyte layer 0.48g chitosan, 0.48g sodium alginate and 4ml glycerol were stirred evenly to obtain a mixture; the mixture was heated at 90°C for 30 minutes; the mixture was then allowed to stand and cool at room temperature for 24 hours to obtain a hydrogel; the hydrogel was immersed in 2M ZnSO4 + 0.1M MnSO4 electrolyte for 4 hours to obtain the first hydrogel electrolyte layer; (3) The first pressure-sensitive conductive hydrogel layer and the first hydrogel electrolyte layer are disposed in the first accommodating space to obtain the self-powered pressure sensor.

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