Claims:We claim
1. A system for recycling and storing energy. The system comprises:
a piezoelectric lamina configured to recycle energy based on applied stress; and
a battery lamina configured to store the energy recycled by the piezoelectric lamina.

2. The system according to Claim 1, further comprising a structural property-enhancing lamina configured to enhance the structural properties of the system.

3. The system according to Claim 2, wherein the piezoelectric lamina comprises:
one or more piezoelectric fibers configured to generate electric charge;
a matrix configured to hold the one or more piezoelectric fibers;
a current-conducting coating layer configured to collect charge generated across the piezoelectric lamina; and
a structural property-enhancing element in contact with at least one of the one or more piezoelectric fibers.

4. The system according to Claim 3, wherein each of the one or more piezoelectric fibers is surrounded by the current-conducting coating layer.

5. The system according to Claim 4, wherein the metal or current-conducting coating layer comprises:
a first metal or current-conducting strip comprising one or more first ring-like structures, wherein the one or more first ring-like structures are configured to secure the first metal or current-conducting strip to the piezoelectric fiber; and
a second metal or current-conducting strip comprising one or more second ring-like structures, wherein the one or more second ring-like structures are configured to secure the second metal or current-conducting strip to the piezoelectric fiber.

6. The system according to Claim 5, wherein the first metal or current-conducting strip and the second metal or current-conducting strip are configured as electrode with opposite polarities.

7. The system according to Claim 2, wherein the battery lamina comprises:
one or more battery fibres configured to store electric charge;
a matrix configured to hold the one or more battery fibers; and
a structural property-enhancing element integrated with at least one of the one or more battery fibers.

8. The system according to Claim 7, wherein each of the one or more battery fibers comprises a fiber core surrounded by a layer of cathode current collector, a layer of cathode, a layer of solid-state electrolyte, a layer of anode, and a layer of anode current collector.

9. The system according to Claim 2, wherein the structural property-enhancing lamina comprises:
one or more fibers configured to provide structural strength to the structural property-enhancing lamina;
a matrix configured to hold the one or more fibers;
a structural property-enhancing element in contact with at least one of the one or more fibers.

10. A system for recycling and storing energy, the system comprises:
a laminate comprising:
a hybrid lamina comprising:
one or more piezoelectric fibers configured to recycle energy based on applied stress,
one or more battery fibers configured to store the energy recycled by the one or more piezoelectric fibers, and
one or more structural property-enhancing elements configured to enhance the structural properties of the lamina; and
a structural property-enhancing lamina configured to enhance the structural properties of the system.

11. The system according to Claim 10, wherein the one or more piezoelectric fibers are positioned in a first zone of the hybrid lamina, wherein the one or more battery fibers are positioned in a second zone of the hybrid lamina, and wherein the first zone and the second zone are electrically connected. , Description:BACKGROUND
Field
[0001] The subject matter in general relates to energy recycling and storage system and in particular, but not exclusively, the subject matter relates to recycling energy by piezoelectric fibers and storing the recycled energy using battery fibers.

Discussion of related field
[0002] Piezoelectric materials can generate electric charges in response to an mechanical stresses applied on the materials. This phenomenon of generating electric charge based on applied mechanical stress is referred to as piezoelectric effect. Piezoelectric materials are being used in and as sensors and energy recycling devices due to their ability to respond to external stimulations. The dynamic mechanical stimulation causes the piezoelectric material to deform with time resulting in an alternating current flow which can be collected, thereby providing a scope to recycle energy.
[0003] The recycled energy is generally stored in a suitable electrical energy storage device. Such energy recycling and storage systems are two distinct systems either bulky in size and/or posses inadequate structural strength, in case of weight sensitive designs. Hence, they cannot be implemented in domains such as aerospace. Therefore, it is desirable to miniaturize energy recycling and storage systems with improved specific structural strength and efficiency.

SUMMARY
[0004] An embodiment provides a unified system for recycling and storing energy, using piezoelectric and solid-state electrochemical effects respectively. The system includes one or more piezoelectric fibers, and one or more battery fibers. The one or more piezoelectric fibers generate electric charge when they undergo deformation due to vibrations from an external source. Further, the one or more battery fibers are configured to store the generated electric charge.
[0005] An embodiment provides a method for harvesting and storing energy, using piezoelectric fibers and battery fibers respectively. The method includes generating electric charge using one or more piezoelectric fibers, wherein the electric charge is generated when the one or more piezoelectric fibers undergo deformation due to vibrations from an external source. The generated electric charge is stored in one or more battery fibers.

BRIEF DESCRIPTION OF DRAWINGS
[0006] Embodiments are illustrated by way of example and not limited in the Figures of the accompanying drawings, in which references to the word like indicate similar elements and in which:
[0007] FIG. 1 is an exemplary configuration of a system 100 for recycling and storing energy using piezoelectric fibers and battery fibers respectively, in accordance with an embodiment;
[0008] FIG. 2 is a cross section of the piezoelectric lamina 102 of FIG. 1, in accordance with an embodiment;
[0009] FIG. 3 is a cross section of the battery lamina 106 of FIG. 1, in accordance with an embodiment;
[0010] FIG. 4 illustrates the battery fiber 302 of FIG. 3, representing different concentric layers, in accordance with an embodiment;
[0011] FIG. 5 is a cross section of the structural property enhancing lamina 104 of FIG. 1, in accordance with an embodiment;
[0012] FIG. 6 is an exemplary configuration of a system 600 for recycling and storing energy, using piezoelectric fibers and battery fibers respectively, in accordance with an embodiment;
[0013] FIG. 7 is an exemplary configuration of a system 700 for recycling and storing energy, using piezoelectric fibers and battery fibers respectively, in accordance with an embodiment;
[0014] FIG. 8 is a cross section of the hybrid lamina 702 of FIG. 7, in accordance with an embodiment;
[0015] FIG. 9 is an exemplary embodiment of a piezoelectric fiber coated with metal or current-conducting electrode pattern, in accordance with an embodiment; and
[0016] FIG. 10 is a flow chart of an exemplary method 1000 for recycling and storing energy using piezoelectric and solid-state electrochemical effects, in accordance with an embodiment.

DETAILED DESCRIPTION
[0017] The following detailed description includes references to the accompanying drawings, which form a part of the detailed description. The drawings show illustrations in accordance with example embodiments. These example embodiments are described in enough detail to enable those skilled in the art to practice the present subject matter. However, it will be apparent to one of ordinary skill in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components, have not been described in detail so as not to unnecessarily obscure aspects of the embodiments. The embodiments can be combined, other embodiments can be utilized, or structural changes can be made without departing from the scope of what is claimed. The following detailed description is, therefore, not to be taken in a limiting sense.
[0018] In this document, the terms “a” or “an” are used, as is common in patent documents, to include one or more than one. In this document, the term “or” is used to refer to a nonexclusive “or,” such that “A or B” includes “A but not B,” “B but not A,” and “A and B,” unless otherwise indicated.
[0019] The embodiments describe a system and a method for recycling and storing energy. The system comprises one or more piezoelectric fibers for recycling energy using piezoelectric effect, and one or more battery fibers for storing the energy recycled by the one or more piezoelectric fibers.
[0020] In an embodiment, the piezoelectric fibers and the battery fibers are comprised in one or more laminae. The plurality of laminae is stacked together to form a laminate.
[0021] The laminate includes a plurality of laminae that may comprise one or more piezoelectric laminae, one or more battery laminae or one or more structural-property enhancing laminae or a combination of two or more of the above. Each lamina may comprise at least one type of fiber such as piezoelectric fibers, battery fibers or structural-property enhancing fibers or a combination of two or more of the above that are embedded within a matrix. The system can have various configurations of lamina and laminate structures and different arrangements of piezoelectric laminae, the battery laminae, and structural-property enhancing laminae are possible.
[0022] FIG. 1 is an exemplary configuration of a system 100 for recycling and storing energy using piezoelectric fibers and battery fibers respectively, in accordance with an embodiment. The system 100 comprises a piezoelectric laminate 110 and a battery laminate 120. The piezoelectric laminate 110 is formed of one or more piezoelectric laminae 102, and one or more structural-property enhancing laminae 104. The battery laminate 120 is formed of one or more battery laminae 106, and one or more structural-property enhancing laminae 104.
[0023] In an embodiment, the count of the piezoelectric laminae 102, and the structural-property enhancing laminae 104 within the piezoelectric laminate 110 may be varied as per the requirement.
[0024] In an embodiment, the relative positioning of each of the one or more piezoelectric laminae 102 and each of the one or more structural-property enhancing laminae 104 within the piezoelectric laminate 110 may be varied as per the requirement.
[0025] In an embodiment, the count of the battery laminae 106, and the structural-property enhancing laminae 104 within the battery laminate 120 may be varied as per the requirement.
[0026] In an embodiment, the relative positioning of each of the one or more battery laminae 106, and each of the one or more structural-property enhancing laminae 104 within the battery laminate 120 may be varied as per the requirement. An example arrangement of the piezoelectric lamina 102, the battery lamina 106 and the structural-property enhancing lamina 104 is shown in FIG. 1.
[0027] In an embodiment, the piezoelectric laminate 110 and the battery laminate 120 are electrically connected such that the energy recycled by the piezoelectric laminate 110 is stored in the battery laminate 120.
[0028] In an embodiment, the piezoelectric laminae 102 are electrically connected to each other to transfer the recycled energy to electrically connected one or more battery laminae 106 for storing the recycled energy.
[0029] FIG. 2 is a cross section of the piezoelectric lamina 102 of FIG. 1, in accordance with an embodiment. The piezoelectric lamina 102 comprises one or more piezoelectric fibers 202, a matrix 206, a metal coating layer 210 configured as a contact electrode, and one or more structural property enhancing elements 204 (depicted as a concentric black layer for ease of understanding) surrounding each of the one or more piezoelectric fibers 202, as shown in FIG. 2.
[0030] Each of the one or more piezoelectric fibers 202 in the piezoelectric lamina 102 may have a planar or non-planar structure. In an embodiment, the one or more piezoelectric fibers 202 may either be randomly dispersed in the matrix 206 or may be arranged in a predefined pattern in the matrix 206.
[0031] In an embodiment, the structural property-enhancing elements 204 are dispersed in the matrix 206 for improving the structural properties of the piezoelectric lamina 102. The structural property-enhancing elements 204 may include one or more carbon-nanostructures such as carbon-nanotubes, graphene or any other high modulus and/or high strength materials known in the art.
[0032] In another embodiment, the structural property-enhancing elements 204 may be grown on the surface of the piezoelectric fibers 202 by techniques known in the art. Further, the growth of the structural property-enhancing elements 204 may be controlled by techniques known in the art. For example, the structural property-enhancing elements 204 may be controlled to grow radially or axially on the surface of the piezoelectric fibers 202.
[0033] The matrix 206 is configured to hold the one or more piezoelectric fibers 202, the one or more structural property-enhancing elements 204, and the metal coating layer 210 together within the piezoelectric lamina 102, as shown in FIG. 2.
[0034] In an embodiment, the matrix 206 may include conventional resin materials such as the epoxy resin or piezoelectric polymer films like poly-vinylidene fluoride or any other resin materials known in the art.
[0035] The metal or current-conducting coating layer 210 is embedded within the matrix 206 covering both the top and bottom of the piezoelectric lamina 102, such that the metal or current-conducting coating layer 210 is electrically connected to the one or more piezoelectric fibers 202. The metal or current-conducting coating layer 210 is configured to act as an electrode pair for collecting charges generated across the piezoelectric lamina 102.
[0036] In an embodiment, the metal or current-conducting coating layer 210 may be used in the form of inter-digitated electrodes as a pattern over the entire lamina.
[0037] FIG. 9 is an isometric view of a piezoelectric fiber 202 where the metal or current-conducting coating layer 210 may be positioned or patterned over each piezoelectric fiber 202, in accordance with an embodiment. The metal or current-conducting coating pattern includes two strips 902 and 906. The strip 902 includes a plurality of ring-like structures 904 while the strip 906 includes a plurality of ring-like structures 908. The plurality of ring-like structures 904 and 908 are configured to secure the strips 902 and 906 to the piezoelectric fiber 202.
[0038] The strips 902 and 906 act as electrodes for providing electrical contact. In order to avoid shorting, the strip 902 may be coated with an insulating material at least on the surface facing the piezoelectric fiber 202. Further, the strip 906 may be coated with an insulating material at least on the surface facing away from the piezoelectric fiber 202. In an embodiment, in order to avoid shorting, the strips 902 and 906 may be coated with insulating material only at points where strip 902 comes in contact with the strip 906.
[0039] The metal or current-conducting coating pattern comprising of strips 902 and 906 may be made of conducting materials such as copper, platinum, gold or any conducting material known in the art.
[0040] In an embodiment and referring to FIG. 1 and FIG. 2, the one or more piezoelectric fibers 202 are dynamically deformed when the piezoelectric lamina 102 or the piezoelectric laminate 110 experiences vibrations. The deformation of the one or more piezoelectric fibers 202 generates electric charges across the piezoelectric lamina 102. The electric charges thus generated are collected by the metal coating layer 210.
[0041] FIG. 3 is a cross section of the battery lamina 106 of FIG. 1, in accordance with an embodiment. The battery lamina 106 comprises one or more battery fibers 302, a matrix 306, and one or more structural property-enhancing elements 304 (depicted as a concentric black layer for ease of understanding) surrounding each of the one or more battery fibers 302, as shown in FIG. 3.
[0042] FIG. 4 illustrates the battery fiber 302 of FIG. 3, representing different concentric layers in a protruding manner for the sake of understanding, in accordance with an embodiment. Each of the one or more battery fibers 302 includes a fiber core 406. The fiber core 406 is surrounded by a plurality of concentric layers that form a battery fiber 302. The fiber core 406 is coated with a layer of cathode current collector 410. Further, the cathode current collector 410 is surrounded by a cathode layer 408. Furthermore, the cathode layer 408 is surrounded by a solid electrolyte layer 404. Furthermore, the solid electrolyte layer 404 is coated with a layer of anode based material 402 which in turn is coated with a layer of anode current collector 412. It shall be understood that the arrangement of the layers can be modified, and different new arrangements are also possible. In an embodiment it is also possible to further coat the anode current collector 412 or the fibre core 406 with structural and/or electrical property enhancer (s).
[0043] In an exemplary embodiment, the fiber core 406 may have a diameter in the range of 33 to 150 micrometers. The thickness of the cathode layer 408 could be in the range of 0.1 to 3 microns, whereas the thickness of the cathode current collector layer 410 and anode current collector layer 412 may be 0.3 to 0.5 microns and the thickness of the solid-state electrolyte layer 404 may be 1.5 to 3.0 microns.
[0044] In an exemplary embodiment, the fiber core 406 may comprise but not be limited to carbon-based materials such as fibrous carbon nanostructures, carbides, carbon-containing derivatives, metals, and alloys of metals, among others. The fiber core 406 may comprise oxide derivatives of elements such as silicon, aluminium, and semiconductor materials, among others. The fiber core 406 may comprise polymeric substrates such as nylon, polyamides, polyethylene, cellulose and other conventional substrates know in the art.
[0045] In an exemplary embodiment, the cathode layer 408 may comprise oxide or phosphate derivatives of lithium with other metals such as cobalt, manganese, iron, nickel, cobalt, aluminium, titanium, vanadium and other cathode-based materials such as metal oxides and polymers.
[0046] In an exemplary embodiment, the cathode current collector 410 and the anode current collector 412 may comprise nickel, cobalt, zinc, tin, platinum, palladium, iron, copper, and metal alloys, among other metals.
[0047] In an exemplary embodiment, the solid electrolyte layer 404 is configured to transport ions and electrons across the cathode layer 408 and anode layer 402 that could be made from materials comprising but not limiting to oxynitride-based derivatives of lithium with elements like phosphorous, carbon, silicon, niobium, tungsten and tantalum, among others. The solid electrolyte layer 404 may comprise lithium or other metal-based glassy substrates including silicates and borosilicate of lithium and metal-based polymeric and ceramic substrates, among others.
[0048] In an exemplary embodiment, the anode layer 402 may comprise but not be limited to carbon-based materials, metals and alloys of metals belonging to alkali earth group or alkaline earth group, transition group metals and alloys of transition group metals with lithium or other metals.
[0049] In an embodiment, the one or more battery fibers 302 may either be randomly dispersed in the matrix 306 or may be arranged in a predefined pattern in the matrix 306.
[0050] In an embodiment, the structural property-enhancing elements 304 are dispersed in the matrix 306 for improving the structural properties of the battery lamina 106. The structural property-enhancing elements 304 may include one or more carbon-nanostructures such as carbon-nanotubes, graphene or any other high modulus and/or high strength materials known in the art.
[0051] The matrix 306 is configured to hold the one or more battery fibers 302, and the one or more structural property-enhancing elements 304 together within the battery lamina 106, as shown in FIG. 3.
[0052] In an embodiment, the matrix 306 may include conventional resin materials such as the epoxy resin or any other resin known in the art.
[0053] FIG. 5 is a cross section of the structural property-enhancing lamina 104 of FIG. 1, in accordance with an embodiment. The structural property-enhancing lamina 104 comprises one or more carbon-based or other typical structural fibers 502, a matrix 506, and one or more structural property-enhancing elements 504 (depicted as concentric black layer for ease of understanding) surrounding each of the one or more carbon-based or other typical structural fibers 502, as shown in FIG. 5. The structural property-enhancing lamina 104 is configured to enhance the overall structural properties of the piezoelectric laminate 110 and the battery laminate 120.
[0054] In an embodiment, each of the one or more carbon-based or other typical structural fibers 502 in the structural property-enhancing lamina 104 may have a planar or non-planar structure. The one or more carbon based-fibers 502 may include carbon source material having very high carbon content or any other structural property-enhancing materials known in the art.
[0055] In an embodiment, the structural property-enhancing elements 504 are dispersed in the matrix 506 for improving the structural properties of the structural property-enhancing lamina 104. The structural property-enhancing elements 504 may include one or more carbon-nanostructures such as carbon-nanotubes, graphene or any other high modulus and/or high strength materials known in the art.
[0056] In an embodiment, the structural property-enhancing elements 504 may also include electrochemical property-enhancing elements.
[0057] The matrix 506 is configured to hold the one or more carbon-based or other typical structural fibers 502, and the one or more structural property-enhancing elements 504 together within the structural property-enhancing lamina 104, as shown in FIG. 5.
[0058] In an embodiment, the matrix 506 may include conventional resin materials such as the epoxy resin or any other resin known in the art.
[0059] FIG. 6 is an exemplary configuration of a system 600 for recycling and storing energy using piezoelectric and solid-state electrochemical effects, in accordance with an embodiment. The system 600 shows arrangement of the one or more piezoelectric laminae 102, the one or more battery laminae 106, and the one or more structural property-enhancing laminae 104 within a single laminate 610.
[0060] In an embodiment, the count of the piezoelectric laminae 102, the battery laminae 106, and the structural property-enhancing laminae 104 within the single laminate 610 may be varied as per the requirement.
[0061] In an embodiment, the relative positioning of each of the one or more piezoelectric laminae 102, each of the one or more battery laminae 106, and each of the one or more structural property-enhancing laminae 104 within the single laminate 610 may be varied as per the requirement. An example arrangement of the piezoelectric laminae 102, the battery laminae 106 and the structural property-enhancing laminae 104 within a single laminate 610 is shown in FIG. 6.
[0062] In an embodiment, the piezoelectric laminae 102, and the battery laminae 106 within the single laminate 610 are electrically connected through an interfacing circuit such that the energy recycled by the piezoelectric laminae 102 is stored in the battery laminae 106.
[0063] FIG. 7 is an exemplary configuration of a system 700 for recycling and storing energy using piezoelectric and solid-state electrochemical effects, in accordance with an embodiment. The system 700 comprises one or more hybrid laminae 702 and the one or more structural property-enhancing laminae 104.
[0064] FIG. 8 is a cross section of the hybrid lamina 702 of FIG. 7, in accordance with an embodiment. The hybrid lamina 702 comprises the one or more piezoelectric fibers 202, the one or more battery fibers 302, a matrix 802, one or more structural property-enhancing elements 204 (depicted as a concentric black layer for ease of understanding) surrounding each of the one or more piezoelectric fibers 202, and the one or more structural property-enhancing elements 304 (depicted as a concentric black layer for ease of understanding) surrounding each of the one or more battery fibers 302, as shown in FIG. 8.
[0065] In an embodiment, the hybrid lamina 702 comprises a plurality of zones (not shown in figures). Further, each of the plurality of zones may include at least one of piezoelectric fibers 202, battery fibers 302, and combination of piezoelectric fibers 202 and battery fibers 302.
[0066] In an embodiment, the zones comprising piezoelectric fibers 202, and the zones comprising the battery fibers 302 within the hybrid lamina 702 are electrically connected using an interfacing circuit such that the energy recycled by the zone comprising the piezoelectric fibers 202 is stored in the zone comprising the battery fibers 302 such that each hybrid lamina 702 of system 700 is capable of recycling and storing energy.
[0067] In the instant embodiment, the electric charge generated across the piezoelectric fibers 202 may be collected as explained with respect to FIG. 9.
[0068] The matrix 802 comprises conventional resin materials such as epoxy resin, piezoelectric materials such as poly-vinylidene fluoride of any other resin known in the art.
[0069] In an embodiment, the relative structural arrangement and the composition of the various laminae including the one or more hybrid laminae 702 and the one or more structural property-enhancing laminae 104 could be varied as per the properties desired in the field of application.
[0070] In an embodiment, the one or more battery fibers 302 are interconnected in series, parallel or combination of series and parallel thereof. Further, the interconnection may be static in nature, wherein the connections are made in series, parallel or a combination of series and parallel circuits. Furthermore, the interconnection may be dynamic in nature, wherein the nature of connections can be changed with respect to time.
[0071] In an exemplary embodiment, the laminates (110, 120, 610, and 710) are fabricated using prepregs in an autoclave or in a single mold using resin infusion molding techniques such as Vacuum Assisted Resin Transfer Molding (VARTM), and any other conventional infusion molding techniques, among other techniques known in the art.
[0072] FIG. 10 is a flow chart of an exemplary method 1000 for recycling and storing energy using piezoelectric and solid-state electrochemical effects, in accordance with an embodiment. At step 1002, the one or more piezoelectric fibers 202 undergo dynamic deformations due to vibrations from an external source and generate electric charges. At step 1004, the generated electric charge is collected by the metal or current-conducting coating layer 210 and transferred to the one or more battery fibers 302, such that the generated electric charge is stored in the one or more battery fibers 302.
[0073] Although embodiments have been described with reference to specific example embodiments, it will be evident that various modifications and changes may be made to these embodiments without departing from the broader spirit and scope of the system and method described herein. Accordingly, the specification and drawings are to be regarded in an illustrative rather than a restrictive sense.
[0074] The processes above are described as sequence of steps. This was done solely for the sake of illustration. Accordingly, it is contemplated that some steps may be added, some steps may be omitted, the order of the steps may be re-arranged, or some steps may be performed simultaneously.
[0075] Many alterations and modifications of the present invention will no doubt become apparent to a person of ordinary skill in the art after having read the foregoing description. It is to be understood that the phraseology or terminology employed herein is for the purpose of description and not of limitation. It is to be understood that the description above contains many specifications; these should not be construed as limiting the scope of the invention but as merely providing illustrations of some of the personally preferred embodiments of this invention.