Composite material structure battery with carbon fiber and fiber battery two-dimensional braided structure and preparation method of composite material structure battery

Abstract

The invention provides a composite material structure battery with a carbon fiber and fiber battery two-dimensional braided structure and a preparation method, and belongs to the technical field of composite material structure batteries. Comprising the following steps: performing two-dimensional weaving on a carbon fiber bundle and a fiber battery to enhance the mechanical properties of the structural battery in the axial direction and the transverse direction. The carbon fiber bundles used may be of 1k, 3k, 6k, 12k, 24k. The used fiber battery is a fiber-based battery taking one or more fibers as a substrate. The carbon fiber bundles and the fiber batteries can be woven into the fabric by adopting a plain weaving mode, a twill weaving mode and a satin weaving mode through a manual weaving mode or a machine weaving mode. The weaving structure is prepared into the structural battery through a liquid forming process, and the bearing capacity of the structural battery in multiple directions can be improved at the same time on the premise that the energy storage capacity of the structural battery is not changed through the method.

Description

Technical Field

[0001] The invention relates to a composite material structure battery of a two-dimensional woven structure of carbon fiber and fiber battery and a preparation method thereof, belonging to the technical field of composite material structure batteries. Background Art

[0002] At present, lithium-ion batteries are widely used in energy storage batteries and power batteries. Traditional lithium-ion batteries are large in size, heavy in weight, and have the risk of thermal runaway explosion, which always restricts the further development of batteries. In recent years, composite lithium-ion structural battery technology has gradually developed. It has both load-bearing and energy storage capabilities. While ensuring the mechanical properties of the structure, it has excellent energy storage characteristics, and can realize the integration of the structure and energy storage of composite materials. As an emerging battery structure, fiber batteries have the characteristics of large aspect ratio, strong structural design, and high energy density. Chinese patent CN 219800958 U (published on October 3, 2023) discloses a long-life flexible fiber battery. Although this fiber battery has a high energy density, due to its own low mechanical strength and modulus, it is easy to be used as a weak point in mechanical properties after preparing a composite lithium-ion structural battery. It is first destroyed as a defect during the load-bearing process of the composite structural battery. The article also mentions that the fiber battery is flexible and can be woven.

[0003] At this stage, there are inventions that integrate fibers and fiber batteries to achieve flexible wearable fabric design. Chinese patent CN 115020899 A (published on September 6, 2022) discloses a method for integrating all-fabric power supply and light-emitting devices, which is to integrate electroluminescent fibers and fiber batteries. However, the fibers woven with fiber batteries in this patent are electrochromic fibers, which have poor load-bearing capacity. After weaving with fiber batteries, the mechanical strength of the structure cannot be greatly improved.

[0004] Therefore, there is an urgent need in the art for a composite material structure battery and a preparation method based on a two-dimensional woven structure of carbon fiber and fiber battery. Summary of the invention

[0005] The purpose of the present invention is to solve the problem of limited strength of structural batteries caused by weak mechanical properties of fiber batteries in existing composite material structural battery technology based on fiber batteries.

[0006] In order to achieve the purpose of solving the above-mentioned problems, the technical solution adopted by the present invention is to provide a composite material structure battery of a two-dimensional woven structure of carbon fiber and fiber battery and a preparation method.

[0007] In a first aspect of the present invention, a composite material structure battery design and preparation method based on a two-dimensional woven structure of carbon fiber and fiber battery is provided, comprising the following steps:

[0008] Step 1, using a carbon fiber bundle containing a fixed number of carbon fibers as warp yarn and a fiber battery as weft yarn;

[0009] Step 2, weaving the carbon fiber bundle and the fiber battery into a two-dimensional fabric through two-dimensional weaving;

[0010] Step 3: The two-dimensional fabric in step 2 is directly solidified after liquid molding, or the two-dimensional fabric in step 2 is first mixed and layered with dry carbon fiber and then prepared by liquid molding to obtain a structural battery.

[0011] Preferably, in step 1, the number of carbon fibers in the carbon fiber bundle is 3k, 6k, 12k or 24k, and the carbon content of the carbon fibers is between 93% and 99%.

[0012] Preferably, in the step 1, the diameter of the fiber battery used is between 0.1 and 5 mm, the length of the fiber battery is not less than 50 mm, the aspect ratio is greater than 10, and the energy density of a single fiber battery is between 5 and 200 watt-hours per kilogram; more preferably, the diameter of the fiber battery is between 1 and 2 mm, and the length is between 100 and 300 mm.

[0013] Preferably, in step 2, the weaving structure of the two-dimensional fabric is plain weave, satin weave, twill weave, basket weave, woven weave, or imitation woven weave, and the weaving method can be machine weaving or hand weaving.

[0014] Preferably, in step 2, the spacing between the carbon fiber bundles serving as warp yarns is between 0.05 and 5 mm, and the spacing between the fiber batteries is between 0.05 and 5 mm; more preferably, the spacing between the carbon fiber bundles and the spacing between the fiber batteries are both between 0.05 and 5 mm.

[0015] Preferably, in step 3, the liquid molding method includes vacuum assisted resin transfer molding process, resin transfer molding, vacuum assisted resin transfer molding; more preferably, resin transfer molding is used.

[0016] Preferably, in step 3, the resin infusion pressure of the liquid molding process is between -0.101 and 1.0 MPa; more preferably, the resin infusion pressure is between 0.1 and 0.5 MPa.

[0017] Preferably, in step 3, the resin used for liquid molding is a modified or unmodified epoxy resin, and the curing temperature of the resin is between 20 and 100° C. and the curing time is within 1 to 24 hours.

[0018] Preferably, in the step 3, the structural battery is prepared by directly liquid molding the woven structure, or it can be first mixed with dry carbon fiber and layered, and then prepared by liquid molding; more preferably, the two-dimensional fabric is mixed with dry carbon fiber and layered, and then the structural battery is prepared by liquid molding and curing.

[0019] Preferably, in step 3, the carbon fibers in the hybrid ply are pre-cut to leave space for the woven structure, and the carbon content of the dry carbon fibers in the hybrid ply is between 93% and 99%; more preferably, the dry carbon fibers are unidirectional cloth or fabric.

[0020] The second aspect of the present invention provides a composite material structural battery based on a two-dimensional woven structure of carbon fiber and fiber battery prepared by the above method. The woven structure can increase the longitudinal (i.e., axial) tensile strength of the structural battery by 10 to 350%, and the transverse (i.e., radial) tensile strength of the fiber battery by 10 to 350%.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] The present invention uses carbon fiber bundles and fiber batteries for two-dimensional weaving, and applies the obtained two-dimensional weaving structure to the preparation of structural batteries, thereby achieving improvements in the longitudinal tensile strength and transverse tensile strength of the structural batteries. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 Schematic diagram of the plain fabric structure based on carbon fiber bundles and fiber batteries;

[0024] Figure 2 Schematic diagram of the satin fabric structure based on carbon fiber bundles and fiber batteries.

[0025] Figure numerals: 1. carbon fiber bundle; 2. fiber battery. DETAILED DESCRIPTION

[0026] In order to make the present invention more clearly understood, a preferred embodiment is described in detail with reference to the accompanying drawings as follows:

[0027] like Figure 1-2 As shown, the present invention provides a composite material structure battery of a two-dimensional woven structure of carbon fiber and fiber battery and a preparation method.

[0028] Example 1

[0029] Use 12k carbon fiber bundles (about 93% graphitization degree) as warp yarn, and fiber batteries with a diameter of 0.5mm and a length of 100mm as weft yarn, and weave them into plain fabrics by hand weaving. The gap between the fiber batteries is 0.5mm, and the gap between the carbon fiber bundles is 0.1mm. The carbon fiber bundle and the fiber battery woven structure are directly vacuum-assisted resin infusion molded using epoxy resin infused at room temperature, and cured at 25°C for 12 hours to obtain a structural battery containing a woven structure. Compared with the unwoven structure, the tensile strength of the structural battery in the axial direction of the fiber battery is increased by 30%, and the tensile strength in the radial direction of the fiber battery is increased by 100%.

[0030] Example 2

[0031] 3k carbon fiber bundles (graphitization degree about 98%) are used as warp yarns, and fiber batteries with a diameter of 1.9mm and a length of 210mm are used as weft yarns, and they are woven into plain fabrics by hand weaving. Figure 1 As shown. The gap between the fiber batteries is 1.5mm, and the gap between the carbon fiber bundles is 0.2mm. The middle part of the 6-layer dry carbon fiber (graphitization degree is about 98%) unidirectional cloth is cut in advance, and the woven structure is embedded in the dry carbon fiber unidirectional cloth to form a preformed structure. The preformed structure is vacuum-assisted resin infusion molded using epoxy resin infused at room temperature, and cured at 40°C for 12 hours to obtain a composite lithium-ion structural battery with an embedded woven structure. Compared with the unwoven structure, the tensile strength of the structural battery in the axial direction of the fiber battery is increased by 40%, and the tensile strength in the radial direction of the fiber battery is increased by 300%.

[0032] Example 3

[0033] Use 24k carbon fiber bundles (graphitization degree of about 98%) as warp yarns, and fiber batteries with a diameter of 1.0mm and a length of 300mm as weft yarns, and weave them into twill fabrics by machine weaving. The gap between the fiber batteries is 0.2mm, and the gap between the carbon fiber bundles is 0.05mm. The middle part of 10 layers of dry carbon fiber (graphitization degree of about 98%) unidirectional cloth is cut in advance, and the woven structure is embedded in the dry carbon fiber unidirectional cloth to form a preformed structure. The preformed structure is vacuum-assisted resin infusion molded using epoxy resin infused at room temperature, and cured at 60°C for 4 hours to obtain a composite lithium-ion structural battery with an embedded woven structure. Compared with the unwoven structure, the tensile strength of the structural battery in the axial direction of the fiber battery is increased by 45%, and the tensile strength in the radial direction of the fiber battery is increased by 350%.

[0034] The above is only a preferred embodiment of the present invention, and is not any formal or substantial limitation of the present invention. It should be pointed out that ordinary technicians in this technical field can make several improvements and supplements without departing from the present invention, and these improvements and supplements should also be regarded as the protection scope of the present invention. Any technician familiar with this profession, without departing from the spirit and scope of the present invention, can make some changes, modifications and equivalent changes made by using the technical content disclosed above, which are equivalent embodiments of the present invention; at the same time, any changes, modifications and evolutions of any equivalent changes made to the above embodiments based on the essential technology of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. A design and preparation method for a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery, characterized in that: The following steps are involved: Step 1: Using a carbon fiber bundle containing a fixed number of carbon fibers as warp yarn and a fiber battery as weft yarn; Step 2: Weaving the carbon fiber bundles and the fiber battery into a two-dimensional fabric through two-dimensional weaving; Step 3: The two-dimensional fabric in step 2 is directly solidified after liquid molding, or the two-dimensional fabric in step 2 is mixed and layered with dry carbon fiber and then liquid molded to obtain a structural battery.

2. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In step 1, the number of carbon fibers in the carbon fiber bundle is 3k, 6k, 12k or 24k, and the carbon content of the carbon fibers is between 93% and 99%.

3. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In the step 1, the diameter of the fiber battery used is between 0.1 and 5 mm, the length of the fiber battery is not less than 50 mm, the aspect ratio is greater than 10, and the energy density of a single fiber battery is between 5 and 200 watt-hours per kilogram.

4. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In the step 2, the weaving structure of the two-dimensional fabric is plain weave, satin weave, twill weave, basket weave, woven weave or imitation woven weave, and the weaving method is machine weaving or hand weaving.

5. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In the step 2, the spacing between the carbon fiber bundles serving as the warp yarns is between 0.05 and 5 mm, and the spacing between the fiber cells is between 0.05 and 5 mm.

6. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In step 3, the liquid molding method is resin transfer molding.

7. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In step 3, the resin infusion pressure during the liquid molding process is between -0.101 and 1.0 MPa.

8. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In step 3, the carbon fibers in the mixed layer are pre-cut, and the carbon content of the dry carbon fibers in the mixed layer is between 93% and 99%.

9. The design and preparation method of a composite material structure battery based on a two-dimensional woven structure of carbon fiber and fiber battery according to claim 1, characterized in that: In the step 3, the dry carbon fiber is a unidirectional cloth or fabric.

10. A composite structural battery based on a two-dimensional woven structure of carbon fiber and fiber battery, prepared by the method according to any one of claims 1 to 9, wherein the woven structure increases the longitudinal tensile strength of the structural battery by 10 to 350% and the transverse tensile strength by 10 to 350%.

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