A lithium-carbon fluoride battery

Abstract

This utility model relates to the field of battery technology, and more particularly to a lithium fluoride carbon battery, comprising an aluminum-plastic film shell, a battery cell, a positive electrode external tab, and a negative electrode external tab. The battery cell is disposed inside the aluminum-plastic film shell, and the positive and negative electrode external tabs are respectively disposed on the sides of the aluminum-plastic film shell. The battery cell includes a positive electrode plate, a diaphragm, a negative electrode plate, and an electrolyte. The battery cell has a stacked cell structure, with each stack consisting of a positive electrode plate, a diaphragm, and a negative electrode plate stacked sequentially from bottom to top. The positive electrode plate includes a positive electrode slurry layer and an aluminum foil, with the positive electrode slurry layer coated on both sides of the aluminum foil. Multiple through holes are provided on the positive electrode plate. This utility model effectively solves the problem of electrode polarization that easily occurs during discharge in existing lithium fluoride carbon batteries, significantly improving the actual specific capacity and discharge rate performance of lithium fluoride carbon batteries, greatly enhancing the power output and safety characteristics of lithium fluoride carbon batteries, and making them suitable for widespread application.

Description

Technical Field

[0001] This utility model relates to the field of battery technology, and in particular to a lithium fluoride carbon battery. Background Technology

[0002] Currently, lithium fluoride (Li / CF4) batteries are showing increasingly prominent performance advantages over other batteries in cutting-edge, high-value applications such as aerospace, implantable medical devices, and national defense, demonstrating a certain degree of irreplaceability. x Compared to other batteries, lithium fluoride batteries exhibit numerous superior performance characteristics, such as: high theoretical energy density, reaching over 2100 Wh / kg; extremely low self-discharge rate, with annual degradation of less than 0.5%; wide temperature range adaptability, covering -40℃ to 125℃; and highly environmentally friendly properties. However, several problems exist in industrial applications. For example, the intrinsic electronic conductivity of fluoride carbon, a key electrode material in lithium fluoride batteries, is extremely low. Furthermore, the interfacial contact efficiency between the positive electrode current collector and the electrolyte in traditional lithium fluoride carbon batteries is insufficient, easily leading to significantly increased polarization during high-rate discharge. Consequently, the actual specific capacity of lithium fluoride carbon batteries is far lower than the theoretical value. In addition, existing lithium fluoride carbon battery packaging processes cannot adapt to the battery volume expansion defects associated with high-rate discharge, easily inducing leakage that could lead to thermal runaway or even explosions, posing significant safety hazards and severely shortening battery life.

[0003] In the prior art, patent CN120247009 A discloses a positive electrode sheet for a lithium fluorinated carbon battery, its preparation method, and its application. The positive electrode sheet uses fluorinated graphite as raw material. The preparation of fluorinated graphite involves placing graphite in a fluorination reactor, introducing a fluorinated gas source, and carrying out a fluorination reaction to obtain fluorinated graphite. The fluorinated graphite, conductive agent, binder, and solvent are then mixed uniformly to obtain a positive electrode slurry. This slurry is coated onto a current collector, dried, and then rolled to obtain the positive electrode sheet for the lithium fluorinated carbon battery. This patent utilizes a gas source to remove the heat of reaction, making the fluorination reaction in the preparation of fluorinated graphite relatively safe and stable, thus mitigating the safety hazards caused by overheating during the fluorination process to some extent. Although this method improves the electrochemical performance of the battery, the safety control of the fluorination reaction in industrial applications still requires further research.

[0004] Patent CN120184178A discloses the preparation and application of an aqueous mixed binder positive electrode for soft-pack fluorinated carbon batteries. The aqueous mixed binder is a mixture of one or two of polyacrylonitrile copolymers, polyethylene oxide, and polyvinyl alcohol. This patent addresses the problems of brittleness and poor adhesion when using acrylonitrile copolymer binders alone or polyethylene oxide and polyvinyl alcohol binders alone by employing an aqueous mixed binder to prepare the fluorinated carbon positive electrode. It avoids some drawbacks in the binder preparation process, improves the electrode's processing performance, alleviates the battery electrolyte deficiency problem caused by discharge volume expansion of the positive electrode, and reduces environmental pollution. While this patent improves battery production and processing, it does not show a significant improvement in battery performance.

[0005] Therefore, there is an urgent need to research and develop lithium fluoride carbon batteries with better performance to meet the needs of large-scale industrial applications. Utility Model Content

[0006] The purpose of this invention is to address the problems existing in the prior art by providing a lithium fluoride carbon battery that combines high power output with safety features, and also to ensure the industrial production of lithium fluoride carbon batteries and their promotion and application in related fields.

[0007] The technical solution to the problem of this utility model is: a lithium fluoride carbon battery, comprising an aluminum-plastic film shell, a battery cell, a positive electrode external tab, and a negative electrode external tab. The battery cell is disposed inside the aluminum-plastic film shell, and the positive electrode external tab and the negative electrode external tab are respectively disposed on the side of the aluminum-plastic film shell; wherein, the battery cell is a stacked battery cell structure, and the battery cell includes a positive electrode plate, a diaphragm, a negative electrode plate, and an electrolyte; in the stacked battery cell structure, at least one set of stacked... The stack consists of a positive electrode, a diaphragm, and a negative electrode stacked sequentially from bottom to top. In each stack, the positive electrode has a positive tab, and the negative electrode has a negative tab. Each positive tab is connected to an external positive electrode tab, and each negative tab is connected to an external negative electrode tab. The positive electrode includes a positive electrode paste layer and an aluminum foil, with the positive electrode paste layer coated on both sides of the aluminum foil. Multiple through holes are provided on the positive electrode.

[0008] Furthermore, in the lithium fluoride battery of this invention, the raw materials for preparing the positive electrode slurry layer are ultrapure water, fluoride, activated carbon, conductive agent, binder, and additives.

[0009] Preferably, in the lithium fluoride battery of the present invention, the mass ratio of each raw material for preparing the positive electrode slurry layer, m(ultrapure water):m(fluoride):m(activated carbon):m(conductive agent):m(binder):m(additive), is (70-75):(15-25):(2-6):(1-3):(0.5-1):(0.5-1).

[0010] Preferably, in the lithium fluoride carbon battery of this utility model, the conductive agent is at least one of acetylene black, electrolytic carbon black, carbon nanotubes, carbon fibers and graphite powder; the binder is polyethylene oxide or polytetrafluoroethylene; and the additive is polystyrene-butadiene copolymer.

[0011] Furthermore, in the lithium fluoride battery of this utility model, the positive electrode external tab and the negative electrode external tab are both disposed on the same side of the aluminum-plastic film shell; in the cell, each of the positive electrode tabs is connected to the positive electrode external tab by ultrasonic welding, and each of the negative electrode tabs is connected to the negative electrode external tab by ultrasonic welding.

[0012] Furthermore, in the lithium fluoride carbon battery of this utility model, the material of the positive electrode external tab is metallic aluminum, and the material of the negative electrode external tab is nickel-plated metallic copper; the material of the negative electrode sheet is metallic lithium; the diaphragm is a cellulose diaphragm; the electrolyte composition includes lithium salt and organic solvent, wherein the lithium salt is LiPF6 or LiBF4; the organic solvent is a mixed solvent composed of dimethyl sulfoxide and 1,4-dioxane, with a volume ratio of (1:9) to (7:3); and the electrolyte concentration is 0.8 to 1.2 mol·L⁻¹. -1 The thickness of the positive electrode slurry layer is 167–193 μm.

[0013] Preferably, in the lithium fluoride carbon battery of this utility model, the material of the negative electrode external tab is nickel-plated copper with a nickel plating layer thickness of 1±0.05μm; on the positive electrode sheet, the spacing between adjacent through holes is 5-7mm, and the diameter of the through holes is 0.5±0.05mm; the positive electrode external tab and the negative electrode external tab are both disposed at the edge of the same side of the aluminum-plastic film shell; the thickness of the aluminum-plastic film shell is 70-160 micrometers, and the distance between each side of the aluminum-plastic film shell and each side of the battery cell is 0.5-1.0mm.

[0014] This invention also provides a method for preparing the above-mentioned lithium-carbon fluoride battery, comprising the following steps:

[0015] S01: Fluorocarbon and activated carbon are placed in a mixer for the first stirring; then conductive agent, binder and additives are added and stirred for the second stirring; finally, ultrapure water is added and stirred for the third stirring until the mixture is uniform to obtain the positive electrode slurry.

[0016] S02: Take the positive electrode slurry obtained in step S01 and coat it on aluminum foil to make a positive electrode current collector;

[0017] S03: Take the positive current collector obtained in step S02, roll it and punch holes to make a positive electrode sheet;

[0018] S04: Place the positive electrode sheet obtained in step S03 in an oven to dry;

[0019] S05: The positive electrode sheet obtained after drying in step S04 is stacked with the diaphragm and negative electrode sheet from bottom to top to prepare a stacked cell. The stacking process is repeated to obtain a stacked cell.

[0020] S06: Welding tabs to the battery cell prepared in S05, including welding positive tabs and welding negative tabs;

[0021] S07: Place the battery cell obtained from welding the tabs in step S06 into an oven for drying.

[0022] S08: Place the battery cell obtained after drying in step S07 into an aluminum-plastic film shell, and seal the sides and top of the aluminum-plastic film shell to make an incompletely sealed lithium fluoride carbon battery.

[0023] S09: Inject electrolyte into the unsealed lithium fluoride carbon battery obtained in step S08. After the electrolyte injection is completed, let the battery stand.

[0024] S10: The lithium fluoride carbon battery that has been filled with liquid but not fully encapsulated after being left to stand in step S09 is encapsulated for the first time to make a pre-lithium fluoride carbon battery. Then, it is tested and screened.

[0025] S11: Take the qualified pre-lithium fluorinated carbon battery obtained from the test in step S10 and perform a second packaging. The preparation of the lithium fluorinated carbon battery is completed.

[0026] Furthermore, in the preparation method of the lithium fluoride carbon battery described in this utility model, in step S01, during the first stirring, the rotation speed of the planetary stirrer is 45-55 rpm, the rotation speed of the self-rotating stirrer is 500-1000 rpm, and the stirring time is 10-20 min; during the second stirring, the rotation speeds of both the planetary and self-rotating stirrers remain constant, and the stirring time is 10-20 min; during the third stirring, the rotation speed of the planetary stirrer remains constant, the rotation speed of the self-rotating stirrer is adjusted to 1250-1750 rpm, and the stirring time is 210-270 min; throughout the three stirring processes, the stirring temperature is maintained at 15°C. 35℃; In step S02, the coating speed of the positive electrode slurry on the aluminum foil is 8-12 m / min, and the ambient temperature during the coating process is 80-120℃; In step S03, the positive electrode current collector is rolled and perforated simultaneously. During the rolling process, the rolling speed is 2-4 m / min, and the ambient temperature is 15-35℃; In step S04, the oven for drying the positive electrode sheet is preheated, and the positive electrode sheet is placed in the preheated oven for drying; The drying of the positive electrode sheet is vacuum drying. During the vacuum drying process, the vacuum degree in the oven is -75 to -100 kPa, the temperature is 80-150℃, and the baking time is 12-24 h; In step S05, the positive electrode sheet is dried in a nitrogen atmosphere. The wafers are prepared in a stacked manner. The ambient temperature during the preparation of the stacks is 150–250℃, and the pressure of nitrogen gas supplied to the preparation environment is 0.2–0.6 MPa. In step S06, the tabs are welded using ultrasonic welding. During ultrasonic welding, the welding power is 10–20%, the welding pressure is 0.3–0.5 MPa, and the welding time for each tab is 0.1–0.2 s. In step S07, the oven for drying the battery cells is preheated, and the battery cells are placed in the preheated oven for drying. The drying of the battery cells is vacuum drying. During vacuum drying, the vacuum degree in the oven is -75 to -100 kPa, the temperature is 80–150℃, and the baking time is 12–24 h. In step S08... The sides and top of the aluminum-plastic film casing are vacuum sealed. During the sealing process, the ambient vacuum level is 0.2–0.6 MPa, the ambient temperature is 150–250°C, and the sealing time is 2–6 seconds. In step S09, the liquid injection instrument is a precision liquid injection pump. After liquid injection, the battery is left to stand for 30–60 minutes. During the standing period, the battery is placed upright with the liquid injection port facing upwards. In step S10, the first sealing is a vacuum sealing. During the first sealing process, the ambient vacuum level is -50 to -100 kPa, the ambient temperature is 150–250°C, and the sealing time is 2–6 seconds. The first sealing is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the sealing environment is 0.2–0.6 MPa; In step S11, the second packaging is vacuum packaging; during the second packaging process, the ambient vacuum level is -50 to -100 kPa, the ambient temperature is 150 to 250 °C, and the packaging time is 2 to 6 seconds; the second packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.2 to 0.6 MPa.

[0027] Preferably, in the preparation method of the lithium fluoride carbon battery of this utility model, in step S03, the positive electrode sheet obtained after rolling has puncture holes, the puncture holes are through holes, there are multiple through holes, the spacing between adjacent through holes is 5-7 mm, and the diameter of the through hole is 0.5±0.05 mm; in step S10, the distance between the seal of the first encapsulation and the nearest side of the cell is 3-5 mm; in step S11, the distance between the seal of the second encapsulation and the nearest side of the cell is 0.5-1.0 mm.

[0028] Preferably, in the preparation method of the lithium fluoride carbon battery of the present invention, in step S02, the thickness of the positive electrode slurry layer on the positive electrode current collector after coating is 190-210 μm; in step S03, the thickness of the positive electrode slurry layer on the positive electrode sheet after rolling is reduced by 17-23 μm.

[0029] Compared with existing technologies, the beneficial effects of this utility model are as follows: The lithium fluoride carbon battery provided by this utility model, through the adoption of an innovative battery structure, especially the structural improvement of the positive electrode sheet, effectively solves the problem of electrode polarization during battery discharge caused by the inherent poor conductivity of fluoride carbon, the key material of the positive electrode, in existing technologies. This effectively improves the actual specific capacity and discharge rate performance of the lithium fluoride carbon battery. The lithium fluoride carbon battery manufacturing method provided by this utility model, through highly efficient mechanized operations throughout the entire process, organically coordinates the production processes such as positive electrode material preparation, cell fabrication, and battery packaging, efficiently realizing the industrial production of lithium fluoride carbon batteries. Specifically, by performing rolling and perforation treatment on the positive electrode sheet, the contact area between the electrolyte and the positive electrode sheet is significantly increased, thereby greatly improving the specific capacity performance of the lithium fluoride carbon battery. The three-stage segmented packaging operation effectively solves the problem of leakage caused by battery volume expansion due to high-rate discharge in existing technologies, thereby enhancing the safety and stability of the lithium fluoride carbon battery. For example, even in the event of a short circuit, the lithium fluoride carbon battery will only experience bulging, avoiding dangerous situations such as explosions. Overall, this invention achieves a significant improvement in power output and safety characteristics of lithium fluoride carbon batteries through innovative improvements to battery structure and manufacturing process; it is suitable for large-scale industrial production and manufacturing, and has low economic cost, making it suitable for widespread application. Attached Figure Description

[0030] Figure 1This is a front view schematic diagram of the lithium fluoride carbon battery of this utility model in Example 1;

[0031] Figure 2 This is a three-dimensional structural diagram of the lithium fluoride carbon battery cell of this utility model in Example 1;

[0032] Figure 3 This is a front view schematic diagram of the positive electrode sheet of the lithium fluoride carbon battery of this invention in Example 1;

[0033] Figure 4 for Figure 3 Schematic diagram of the axial structure of the positive electrode sheet;

[0034] Figure 5 The discharge curves of the lithium fluoride carbon batteries prepared in Examples 1-5 at a rate of 0.1C are shown.

[0035] Figure 6 The discharge curves of the lithium fluoride carbon batteries prepared in Examples 1-5 at a 1C rate are shown.

[0036] Figure 7 The discharge curves of the lithium fluoride carbon batteries prepared in Examples 1-5 are shown at a 5C rate.

[0037] As shown in the figure: 1-Positive electrode external tab; 2-Negative electrode external tab; 3-Aluminum-plastic film shell; 4-Diaphragm; 5-Positive electrode sheet; 6-Negative electrode sheet; 7-Positive electrode slurry layer; 8-Aluminum foil. Detailed Implementation

[0038] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but the scope of protection of the present invention is not limited thereto.

[0039] Unless otherwise specified, the experimental methods and instruments used in the following examples are conventional methods.

[0040] Unless otherwise specified, all materials and reagents used in the following examples are commercially available.

[0041] Example 1

[0042] like Figure 1-4As shown, this utility model discloses a lithium fluoride carbon battery, comprising an aluminum-plastic film shell 3, a battery cell, a positive electrode external tab 1, and a negative electrode external tab 2. The battery cell is disposed inside the aluminum-plastic film shell 3, and the positive electrode external tab 1 and the negative electrode external tab 2 are respectively disposed on the side of the aluminum-plastic film shell 3. The battery cell has a stacked cell structure, comprising a positive electrode plate 5, a diaphragm 4, a negative electrode plate 6, and an electrolyte. In the stacked cell structure, at least one set of stacked plates is provided, each set of stacked plates... The plates are all stacked in a bottom-up manner, consisting of the positive electrode plate 5, the diaphragm 4, and the negative electrode plate 6. In each stack, the positive electrode plate 5 is provided with a positive electrode tab, and the negative electrode plate 6 is provided with a negative electrode tab. Each positive electrode tab is connected to the positive external electrode tab 1, and each negative electrode tab is connected to the negative external electrode tab 2. The positive electrode plate 5 includes a positive electrode paste layer 7 and an aluminum foil 8. The positive electrode paste layer 7 is coated on both the front and back sides of the aluminum foil 8. Multiple through holes are provided on the positive electrode plate 5.

[0043] In the above implementation, the material of the positive electrode external tab is aluminum, the diaphragm is a cellulose diaphragm, the material of the negative electrode sheet is lithium, and the material of the negative electrode external tab is nickel-plated copper (hereinafter referred to as nickel-plated copper). Preferably, the thickness of the nickel plating layer of the nickel-plated copper is 1 micrometer.

[0044] In the above implementation, both the positive electrode external tab and the negative electrode external tab are located on the same side of the aluminum-plastic film shell; preferably, both the positive electrode external tab and the negative electrode external tab are located at the edge of the same side of the aluminum-plastic film shell.

[0045] In the above implementation, in the battery cell, each of the positive electrode tabs is connected to the positive external electrode tab by ultrasonic welding, and each of the negative electrode tabs is connected to the negative external electrode tab by ultrasonic welding.

[0046] In the above embodiments, the thickness of the aluminum-plastic film shell is 70-160 micrometers, preferably 100-155 micrometers, and more preferably 151 micrometers. The distance between each side of the aluminum-plastic film shell and each side of the battery cell is 0.5 mm. The through holes on the positive electrode plate can be designed according to actual needs. Preferably, the spacing between adjacent through holes is 5-7 mm, preferably 6 mm. Preferably, the diameter of the through hole is 0.5 ± 0.05 mm, preferably 0.5 mm.

[0047] In the above embodiments, the electrolyte comprises a lithium salt and an organic solvent, wherein the lithium salt is LiPF6; the organic solvent is a mixed solvent composed of dimethyl sulfoxide and 1,4-dioxane in a volume ratio of 1:9; and the electrolyte concentration is 0.8 mol·L⁻¹. -1 .

[0048] In the above embodiments, the thickness of the positive electrode slurry layer on each side of the aluminum foil in the positive electrode sheet is 173 μm; the raw materials for preparing the positive electrode slurry layer are ultrapure water, fluorinated carbon, activated carbon, conductive agent, binder and additive, wherein the conductive agent is acetylene black, the binder is polyethylene oxide, and the additive is polystyrene-butadiene copolymer; the mass ratio of each raw material m(ultrapure water):m(fluorinated carbon):m(activated carbon):m(conductive agent):m(binder):m(additive) is 70:25:2:1:1:1.

[0049] The specific preparation method of the above-mentioned lithium fluoride carbon battery of this utility model includes the following steps:

[0050] S01: Weigh each raw material as shown in Table 1, place fluorinated carbon and activated carbon in the container of the mixer, and turn on the mixer for the first stirring; then add conductive agent, binder and additive to the container and stir for the second stirring; finally add ultrapure water to the container and stir for the third stirring until the mixture is uniform to obtain the positive electrode slurry.

[0051] S02: The positive electrode slurry obtained in step S01 is coated on both sides of the aluminum foil to form a positive electrode current collector;

[0052] S03: Take the positive current collector obtained in step S02 and roll it to form a positive electrode sheet;

[0053] S04: Preheat the oven for drying the positive electrode sheet, and place the positive electrode sheet obtained in step S03 into the preheated oven for vacuum drying.

[0054] S05: In a nitrogen atmosphere, the positive electrode sheet obtained after drying in step S04 is stacked with the diaphragm and the negative electrode sheet from bottom to top to prepare a stacked cell. The stacking process is repeated to obtain a stacked cell.

[0055] S06: Weld tabs to the battery cell prepared in S05. The welding method is ultrasonic welding, including positive tab welding and negative tab welding. The positive tab is an aluminum tab and the negative tab is a copper-plated nickel tab.

[0056] S07: Preheat the oven for drying the battery cells, and place the battery cells obtained in step S06 by welding the tabs into the preheated oven for vacuum drying.

[0057] S08: Place the battery cell obtained after drying in step S07 into an aluminum-plastic film shell, and vacuum seal the sides and top of the aluminum-plastic film shell to produce an incompletely sealed lithium fluoride carbon battery.

[0058] S09: Using a precision injection pump, inject electrolyte into the unsealed lithium fluoride carbon battery obtained in step S08. After the injection is completed, place the battery with the injection port facing upwards and stand upright in the material box.

[0059] S10: Perform the first encapsulation of the lithium fluoride carbon battery that has been filled with liquid but not fully encapsulated after being left to stand in step S09. After encapsulation, cut off the excess aluminum-plastic film at the encapsulation port to make a pre-lithium fluoride carbon battery. Then, test and screen it.

[0060] S11: Take the qualified pre-lithium fluorinated carbon battery obtained from the test in step S10 and perform a second packaging. The preparation of the lithium fluorinated carbon battery is completed.

[0061] In the preparation of the lithium fluoride carbon battery of the present invention:

[0062] In step S01, during the first mixing, the rotation speed of the planetary mixer is 45 rpm, the rotation speed of the self-rotating mixer is 500 rpm, and the mixing time is 10 minutes. During the second mixing, the rotation speeds of both the planetary and self-rotating mixers remain constant, and the mixing time is 10 minutes. During the third mixing, the rotation speed of the planetary mixer remains constant, the rotation speed of the self-rotating mixer is adjusted to 1250 rpm, and the mixing time is 210 minutes. Throughout the three mixing processes, the mixing temperature is maintained at 15°C.

[0063] In step S02, the coating speed of the positive electrode paste on both sides of the aluminum foil is 8m / min, and the ambient temperature during the coating process is 80℃; the thickness of the positive electrode paste on each side of the aluminum foil of the positive electrode current collector is 190μm.

[0064] In step S03, the positive current collector is rolled and perforated simultaneously. During the rolling process, the rolling speed is 2 m / min and the ambient temperature is 15℃. The positive electrode sheet obtained after rolling has perforations, which are through holes. There are multiple through holes, with a spacing of 5 mm between adjacent through holes and a hole diameter of 0.45 mm. The thickness of the positive electrode slurry layer on the positive electrode sheet obtained after rolling is 173 μm, which is 17 μm less than before rolling.

[0065] In step S04, during the vacuum drying process of the positive electrode sheet, the vacuum degree inside the oven is -75 kPa, the temperature is 80°C, and the baking time is 12 hours.

[0066] In step S05, the ambient temperature during the preparation of the stack is 150°C, and the pressure of nitrogen gas supplied to the preparation environment is 0.2 MPa.

[0067] In step S06, during the ultrasonic welding process, the welding power is 10%, the welding pressure is 0.3 MPa, and the ultrasonic welding time for each electrode is 0.1 s;

[0068] In step S07, during the vacuum drying process of the battery cell, the vacuum degree inside the oven is -75kPa, the temperature is 80℃, and the baking time is 12h.

[0069] In step S08, during the vacuum sealing process of the sides and top of the aluminum-plastic film shell, the ambient vacuum level is 0.2MPa, the ambient temperature is 150℃, and the sealing time is 2s.

[0070] In step S09, the battery with the electrolyte inlet facing upwards is placed upright in the material box and left to stand for 30 minutes.

[0071] In step S10, the first packaging is vacuum packaging; during the first packaging process, the ambient vacuum degree is -50kPa, the ambient temperature is 150℃, and the packaging time is 2s; the first packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.2Mpa; the distance between the seal of the first packaging and the nearest side of the cell is 3mm; the testing and screening of pre-lithium fluorinated carbon batteries is preferably based on the combination of terminal voltage and internal resistance testing, and qualified pre-lithium fluorinated carbon batteries are screened out;

[0072] In step S11, the second packaging is vacuum packaging; during the second packaging process, the ambient vacuum degree is -50kPa, the ambient temperature is 150℃, and the packaging time is 2s; the second packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.2Mpa; the distance between the seal of the second packaging and the nearest side of the cell is 0.5mm; the prepared lithium fluoride carbon battery is a soft-pack lithium fluoride carbon battery.

[0073] In the above embodiments, to ensure thorough and uniform mixing of all materials, the mixer is preferably a KRI mixer manufactured by Dongguan KRI Electromechanical Equipment Co., Ltd., model KR-ZKJ-60L. In this type of mixer, the revolving agitator refers to an agitator that revolves around the central axis of the container, its function being macroscopic mixing and circulation of raw materials throughout the container, preventing scaling, crystallization, or sedimentation on the container wall. In this type of KRI mixer, the self-rotating agitator refers to an agitator that revolves around the central axis while also rotating at high speed around its own axis, its function being microscopic mixing and strong local shearing, forming a strong local mixing zone, uniformly dispersing solid particles into the liquid medium, and preventing sedimentation. The implementation of this patent is not limited to this type of mixer; the standard is to achieve the above-mentioned thorough and uniform mixing of all materials.

[0074] The performance of the prepared lithium fluoride carbon battery of this utility model was tested. The preferred testing method was as follows: after placing the soft-pack lithium fluoride carbon battery prepared in the above embodiment at room temperature for 18 to 32 hours, the battery discharge test was performed at different rates using the Xinwei Battery Testing System, with a cutoff voltage of 1.5V.

[0075] The discharge curves obtained from the test are attached. Figure 5-7 As shown in Table 2, the battery performance test results are as follows.

[0076] From Table 2 and Figure 5-7 As can be seen, the soft-pack lithium fluoride batteries prepared in the above embodiments have no voltage hysteresis and obvious polarization in the initial stage of discharge. The battery performance is excellent at different rates of 0.1C, 1C and 5C. After the battery is discharged, no bulging or leakage occurs, indicating that the lithium fluoride battery of this invention has high rate performance and high safety.

[0077] Example 2

[0078] like Figures 1 to 4 As shown, a lithium fluoride carbon battery has the same basic structure as in Example 1, and its basic preparation method and performance testing method are the same as in Example 1. The composition of its positive electrode slurry raw materials is shown in Table 1, and its performance test graph is shown in Table 1. Figure 5-7 The performance test results are shown in Table 2.

[0079] In the above embodiments, the thickness of the nickel plating layer of nickel-plated copper in the negative electrode external tab is preferably 0.95 micrometers; in the positive electrode sheet, the thickness of the positive electrode slurry layer on each side of the aluminum foil is 187 μm; the raw materials for preparing the positive electrode slurry layer are ultrapure water, fluorinated carbon, activated carbon, conductive agent, binder and additives, wherein the conductive agent is carbon black, the binder is polyethylene oxide, and the additive is polystyrene-butadiene copolymer; the mass ratio of each raw material m(ultrapure water):m(fluorinated carbon):m(activated carbon):m(conductive agent):m(binder):m(additives) is 75:15:6:3:0.5:0.5.

[0080] The specific preparation method of the lithium fluoride carbon battery of this invention is the same as that in Example 1, wherein:

[0081] In step S01, during the first mixing, the rotation speed of the planetary mixer is 55 rpm, the rotation speed of the self-rotating mixer is 1000 rpm, and the mixing time is 20 minutes. During the second mixing, the rotation speeds of both the planetary and self-rotating mixers remain constant, and the mixing time is 20 minutes. During the third mixing, the rotation speed of the planetary mixer remains constant, the rotation speed of the self-rotating mixer is adjusted to 1750 rpm, and the mixing time is 270 minutes. Throughout the three mixing processes, the mixing temperature is maintained at 35°C.

[0082] In step S02, the coating speed of the positive electrode paste on both sides of the aluminum foil is 12 m / min, and the ambient temperature during the coating process is 120℃; the thickness of the positive electrode paste on each side of the aluminum foil of the prepared positive electrode current collector is 210 μm.

[0083] In step S03, the positive current collector is rolled and perforated simultaneously. During the rolling process, the rolling speed is 4 m / min and the ambient temperature is 35°C. The positive electrode sheet obtained after rolling has perforations, which are through holes. There are multiple through holes, with a spacing of 7 mm between adjacent through holes and a hole diameter of 0.55 mm. The thickness of the positive electrode slurry layer on the positive electrode sheet obtained after rolling is 187 μm, which is 23 μm less than before rolling.

[0084] In step S04, during the vacuum drying process of the positive electrode sheet, the vacuum degree inside the oven is -100kPa, the temperature is 150℃, and the baking time is 24h.

[0085] In step S05, the ambient temperature during the preparation of the stack is 250°C, and the pressure of nitrogen gas supplied to the preparation environment is 0.6 MPa.

[0086] In step S06, during the ultrasonic welding process, the welding power is 20%, the welding pressure is 0.5 MPa, and the ultrasonic welding time for each electrode is 0.2 s;

[0087] In step S07, during the vacuum drying process of the battery cell, the vacuum degree inside the oven is -100kPa, the temperature is 150℃, and the baking time is 24h.

[0088] In step S08, during the vacuum sealing process of the sides and top of the aluminum-plastic film shell, the ambient vacuum level is 0.6MPa, the ambient temperature is 250℃, and the sealing time is 6s.

[0089] In step S09, the battery with the electrolyte inlet facing upwards is placed upright in the material box and left to stand for 60 minutes.

[0090] In step S10, the first packaging is vacuum packaging; during the first packaging process, the ambient vacuum degree is -100kPa, the ambient temperature is 250℃, and the packaging time is 6s; the first packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.6Mpa; the distance between the seal of the first packaging and the nearest side of the cell is 5mm.

[0091] In step S11, the second packaging is vacuum packaging; during the second packaging process, the ambient vacuum degree is -100kPa, the ambient temperature is 250℃, and the packaging time is 6s; the second packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.6Mpa; the distance between the seal of the second packaging and the nearest side of the cell is 1.0mm; a soft-pack lithium fluoride carbon battery is prepared.

[0092] Example 3

[0093] like Figures 1 to 4 As shown, a lithium fluoride carbon battery has the same basic structure as in Example 1, and its basic preparation method and performance testing method are the same as in Example 1. The composition of its positive electrode slurry raw materials is shown in Table 1, and its performance test graph is shown in Table 1. Figure 5-7 The performance test results are shown in Table 2.

[0094] In the above embodiments, the thickness of the nickel plating layer of nickel-plated copper in the negative electrode tab is preferably 1.05 micrometers; in the positive electrode sheet, the thickness of the positive electrode slurry layer on each side of the aluminum foil is 180 μm; the raw materials for preparing the positive electrode slurry layer are ultrapure water, fluorinated carbon, activated carbon, conductive agent, binder and additives, wherein the conductive agent is carbon nanotubes, the binder is polyethylene oxide, and the additive is polystyrene-butadiene copolymer; the mass ratio of each raw material m(ultrapure water):m(fluorinated carbon):m(activated carbon):m(conductive agent):m(binder):m(additives) is 72:20:4:2:1:1.

[0095] The specific preparation method of the lithium fluoride carbon battery of this invention is the same as that in Example 1, wherein:

[0096] In step S01, during the first mixing, the rotation speed of the planetary mixer is 50 rpm, the rotation speed of the self-rotating mixer is 750 rpm, and the mixing time is 15 min; during the second mixing, the rotation speeds of both the planetary and self-rotating mixers remain unchanged, and the mixing time is 15 min; during the third mixing, the rotation speed of the planetary mixer remains unchanged, the rotation speed of the self-rotating mixer is adjusted to 1500 rpm, and the mixing time is 240 min; throughout the three mixing processes, the mixing temperature is maintained at 25℃.

[0097] In step S02, the coating speed of the positive electrode paste on both sides of the aluminum foil is 10 m / min, and the ambient temperature during the coating process is 100℃; the thickness of the positive electrode paste on each side of the aluminum foil of the positive electrode current collector is 200 μm.

[0098] In step S03, the positive current collector is rolled and perforated simultaneously. During the rolling process, the rolling speed is 3 m / min and the ambient temperature is 25°C. The positive electrode sheet obtained after rolling has perforations, which are through holes. There are multiple through holes, with a spacing of 6 mm between adjacent through holes and a hole diameter of 0.5 mm. The thickness of the positive electrode slurry layer on the positive electrode sheet obtained after rolling is 180 μm, which is 20 μm less than before rolling.

[0099] In step S04, during the vacuum drying process of the positive electrode sheet, the vacuum degree inside the oven is -85 kPa, the temperature is 120°C, and the baking time is 18 hours.

[0100] In step S05, the ambient temperature during the preparation of the stack is 200°C, and the pressure of nitrogen gas supplied to the preparation environment is 0.4 MPa.

[0101] In step S06, during the ultrasonic welding process, the welding power is 15%, the welding pressure is 0.4 MPa, and the ultrasonic welding time for each electrode is 0.15 s.

[0102] In step S07, during the vacuum drying process of the battery cell, the vacuum degree inside the oven is -85kPa, the temperature is 120℃, and the baking time is 18h.

[0103] In step S08, during the vacuum sealing process of the sides and top of the aluminum-plastic film shell, the ambient vacuum degree is 0.4MPa, the ambient temperature is 200℃, and the sealing time is 4s.

[0104] In step S09, the battery with the electrolyte inlet facing upwards is placed upright in the material box and left to stand for 45 minutes.

[0105] In step S10, the first packaging is a vacuum packaging; during the first packaging process, the ambient vacuum level is -75kPa, the ambient temperature is 200℃, and the packaging time is 4s; the first packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.4Mpa; the distance between the seal of the first packaging and the nearest side of the cell is 4mm.

[0106] In step S11, the second packaging is vacuum packaging; during the second packaging process, the ambient vacuum degree is -75kPa, the ambient temperature is 200℃, and the packaging time is 4s; the second packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.4Mpa; the distance between the seal of the second packaging and the nearest side of the cell is 0.75mm; a soft-pack lithium fluoride carbon battery is prepared.

[0107] Example 4

[0108] like Figures 1 to 4As shown, a lithium fluoride carbon battery has the same basic structure as in Example 1, and its basic preparation method and performance testing method are the same as in Example 1. The composition of its positive electrode slurry raw materials is shown in Table 1, and its performance test graph is shown in [Figure 1]. Figure 5-7 The performance test results are shown in Table 2.

[0109] In the above embodiments, the electrolyte comprises a lithium salt and an organic solvent, wherein the lithium salt is LiBF4; the organic solvent is a mixed solvent composed of dimethyl sulfoxide and 1,4-dioxane in a volume ratio of 5:5; and the electrolyte concentration is 1 mol·L⁻¹. -1 .

[0110] In the above embodiments, the thickness of the positive electrode slurry layer on each side of the aluminum foil in the positive electrode sheet is 167 μm; the raw materials for preparing the positive electrode slurry layer are ultrapure water, fluorinated carbon, activated carbon, conductive agent, binder and additives, wherein the conductive agent is carbon fiber, the binder is polytetrafluoroethylene, and the additive is polystyrene-butadiene copolymer; the mass ratio of each raw material m(ultrapure water):m(fluorinated carbon):m(activated carbon):m(conductive agent):m(binder):m(additives) is 70:20:5:3:1:1.

[0111] The specific preparation method of the lithium fluoride carbon battery of this invention is the same as that in Example 1, wherein:

[0112] In step S01, during the first mixing, the rotation speed of the planetary mixer is 47 rpm, the rotation speed of the self-rotating mixer is 600 rpm, and the mixing time is 12 min; during the second mixing, the rotation speeds of both the planetary and self-rotating mixers remain unchanged, and the mixing time is 17 min; during the third mixing, the rotation speed of the planetary mixer remains unchanged, the rotation speed of the self-rotating mixer is adjusted to 1350 rpm, and the mixing time is 220 min; throughout the three mixing processes, the mixing temperature is maintained at 20℃.

[0113] In step S02, the coating speed of the positive electrode paste on both sides of the aluminum foil is 9m / min, and the ambient temperature during the coating process is 90℃; the thickness of the positive electrode paste on each side of the aluminum foil of the positive electrode current collector is 190μm.

[0114] In step S03, the positive current collector is rolled and perforated simultaneously. During the rolling process, the rolling speed is 2 m / min and the ambient temperature is 20°C. The resulting positive electrode sheet has perforations, which are through holes. There are multiple through holes, with a spacing of 5 mm between adjacent through holes and a hole diameter of 0.45 mm. The thickness of the positive electrode slurry layer on the resulting positive electrode sheet after rolling is 167 μm, which is 23 μm less than before rolling.

[0115] In step S04, during the vacuum drying process of the positive electrode sheet, the vacuum degree inside the oven is -80 kPa, the temperature is 100℃, and the baking time is 15 hours.

[0116] In step S05, the ambient temperature during the preparation of the stack is 175°C, and the pressure of nitrogen gas supplied to the preparation environment is 0.3 MPa.

[0117] In step S06, during the ultrasonic welding process, the welding power is 20%, the welding pressure is 0.3 MPa, and the ultrasonic welding time for each electrode is 0.1 s;

[0118] In step S07, during the vacuum drying process of the battery cell, the vacuum degree inside the oven is -90kPa, the temperature is 140℃, and the baking time is 21h.

[0119] In step S08, during the vacuum sealing process of the sides and top of the aluminum-plastic film shell, the ambient vacuum level is 0.5MPa, the ambient temperature is 225℃, and the sealing time is 5s.

[0120] In step S09, the battery with the electrolyte inlet facing upwards is placed upright in the material box and left to stand for 40 minutes.

[0121] In step S10, the first packaging is a vacuum packaging; during the first packaging process, the ambient vacuum level is -60kPa, the ambient temperature is 175℃, and the packaging time is 5s; the first packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.3Mpa; the distance between the seal of the first packaging and the nearest side of the cell is 5mm.

[0122] In step S11, the second packaging is vacuum packaging; during the second packaging process, the ambient vacuum degree is -60kPa, the ambient temperature is 175℃, and the packaging time is 3s; the second packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.5Mpa; the distance between the seal of the second packaging and the nearest side of the cell is 0.6mm; a soft-pack lithium fluoride carbon battery is prepared.

[0123] Example 5

[0124] like Figures 1 to 4 As shown, a lithium fluoride carbon battery has the same basic structure as in Example 1, and its basic preparation method and performance testing method are the same as in Example 1. The composition of its positive electrode slurry raw materials is shown in Table 1, and its performance test graph is shown in Table 1. Figure 5-7 The performance test results are shown in Table 2.

[0125] In the above embodiments, the electrolyte comprises a lithium salt and an organic solvent, wherein the lithium salt is LiBF4; the organic solvent is a mixed solvent composed of dimethyl sulfoxide and 1,4-dioxane in a volume ratio of 7:3; and the electrolyte concentration is 1.2 mol·L⁻¹. -1 .

[0126] In the above embodiments, the thickness of the positive electrode slurry layer on each side of the aluminum foil in the positive electrode sheet is 193 μm; the raw materials for preparing the positive electrode slurry layer are ultrapure water, fluorinated carbon, activated carbon, conductive agent, binder and additives, wherein the conductive agent is graphite powder, the binder is polytetrafluoroethylene, and the additive is polystyrene-butadiene copolymer; the mass ratio of each raw material m(ultrapure water):m(fluorinated carbon):m(activated carbon):m(conductive agent):m(binder):m(additives) is 75:20:2:1.5:0.5:1.

[0127] The specific preparation method of the lithium fluoride carbon battery of this invention is the same as that in Example 1, wherein:

[0128] In step S01, during the first mixing, the rotation speed of the planetary mixer is 53 rpm, the rotation speed of the self-rotating mixer is 900 rpm, and the mixing time is 17 min; during the second mixing, the rotation speeds of both the planetary and self-rotating mixers remain unchanged, and the mixing time is 12 min; during the third mixing, the rotation speed of the planetary mixer remains unchanged, the rotation speed of the self-rotating mixer is adjusted to 1650 rpm, and the mixing time is 260 min; throughout the three mixing processes, the mixing temperature is maintained at 30℃.

[0129] In step S02, the coating speed of the positive electrode paste on both sides of the aluminum foil is 11 m / min, and the ambient temperature during the coating process is 110℃; the thickness of the positive electrode paste on each side of the aluminum foil of the prepared positive electrode current collector is 210 μm.

[0130] In step S03, the positive current collector is rolled and perforated simultaneously. During the rolling process, the rolling speed is 4 m / min and the ambient temperature is 30°C. The positive electrode sheet obtained after rolling has perforations, which are through holes. There are multiple through holes, with a spacing of 7 mm between adjacent through holes and a hole diameter of 0.5 mm. The thickness of the positive electrode slurry layer on the positive electrode sheet obtained after rolling is 193 μm, which is 17 μm less than before rolling.

[0131] In step S04, during the vacuum drying process of the positive electrode sheet, the vacuum degree inside the oven is -90kPa, the temperature is 140℃, and the baking time is 21h.

[0132] In step S05, the ambient temperature during the preparation of the stack is 225°C, and the pressure of nitrogen gas supplied to the preparation environment is 0.5 MPa.

[0133] In step S06, during the ultrasonic welding process, the welding power is 10%, the welding pressure is 0.5 MPa, and the ultrasonic welding time for each electrode is 0.2 s.

[0134] In step S07, during the vacuum drying process of the battery cell, the vacuum degree inside the oven is -80kPa, the temperature is 100℃, and the baking time is 15h.

[0135] In step S08, during the vacuum sealing process of the sides and top of the aluminum-plastic film shell, the ambient vacuum level is 0.3MPa, the ambient temperature is 175℃, and the sealing time is 3s.

[0136] In step S09, the battery with the electrolyte inlet facing upwards is placed upright in the material box and left to stand for 50 minutes.

[0137] In step S10, the first packaging is a vacuum packaging; during the first packaging process, the ambient vacuum level is -90kPa, the ambient temperature is 225℃, and the packaging time is 3s; the first packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.5Mpa; the distance between the seal of the first packaging and the nearest side of the cell is 3mm.

[0138] In step S11, the second packaging is vacuum packaging; during the second packaging process, the ambient vacuum degree is -90kPa, the ambient temperature is 225℃, and the packaging time is 5s; the second packaging is carried out in a nitrogen environment, and the pressure of nitrogen supplied to the packaging environment is 0.3Mpa; the distance between the seal of the second packaging and the nearest side of the cell is 0.8mm; a soft-pack lithium fluoride carbon battery is prepared.

[0139] Based on the tests conducted on the lithium-carbon fluoride batteries of Examples 1-5, as shown in Table 2 and... Figure 5-7 The test results show that the soft-pack lithium fluoride batteries prepared in Examples 1-5 above do not exhibit voltage hysteresis or obvious polarization at the beginning of discharge. The batteries perform well at different rates of 0.1C, 1C, and 5C. Furthermore, no bulging or leakage occurs after the batteries are discharged, indicating that the lithium fluoride batteries of this invention have high rate performance and high safety.

[0140] Overall, this invention effectively solves the problem of electrode polarization during battery discharge caused by the inherent poor conductivity of carbon fluoride, a key material in the positive electrode, through innovative battery structure, particularly improvements in the structure and materials of the positive electrode. This significantly improves the actual specific capacity and discharge rate performance of lithium carbon fluoride batteries. Simultaneously, the innovative lithium carbon fluoride battery manufacturing method achieves highly efficient mechanized operation throughout the entire process, organically coordinating the production processes of positive electrode material preparation, cell fabrication, and battery packaging. This enables the efficient industrial production of lithium carbon fluoride batteries. Specifically, the positive electrode sheet undergoes rolling and perforation treatment. This significantly increases the contact area between the electrolyte and the positive electrode, thereby greatly improving the specific capacity performance of lithium fluorocarbon batteries. The three-stage encapsulation process effectively solves the problem of leakage caused by battery volume expansion due to high-rate discharge, a problem present in existing technologies. This enhances the safety and stability of lithium fluorocarbon batteries; for example, even in the event of a short circuit, the lithium fluorocarbon battery will only exhibit bulging, avoiding dangerous situations such as explosions. Thus, it significantly improves the power output, safety characteristics, and stability and reliability of lithium fluorocarbon batteries. It is suitable for large-scale industrial production and manufacturing, and its low cost makes it suitable for widespread application.

[0141] This utility model is not limited to the above-described embodiments. Any obvious improvements or modifications made by those skilled in the art to the above-described embodiments will not exceed the scope of the concept of this utility model and the protection scope of the appended claims.

[0142] Table 1

[0143]

[0144]

[0145] Table 2

[0146]

Claims

1. A lithium fluoride carbon battery, comprising an aluminum-plastic film casing, a battery cell, a positive electrode external tab, and a negative electrode external tab, wherein the battery cell is disposed inside the aluminum-plastic film casing, and the positive electrode external tab and the negative electrode external tab are respectively disposed on the side of the aluminum-plastic film casing; characterized in that, The battery cell has a stacked cell structure, and the battery cell includes a positive electrode, a diaphragm, a negative electrode, and an electrolyte; in the stacked cell structure, there is at least one set of stacked cells, and each set of stacked cells is a structure in which the positive electrode, diaphragm, and negative electrode are stacked sequentially from bottom to top; In each stack of plates, the positive electrode plate is provided with a positive electrode tab, and the negative electrode plate is provided with a negative electrode tab. Each positive electrode tab is connected to the external positive electrode tab, and each negative electrode tab is connected to the external negative electrode tab. The positive electrode sheet includes a positive electrode slurry layer and an aluminum foil, and the positive electrode slurry layer is coated on both sides of the aluminum foil. Multiple through holes are provided on the positive electrode sheet.

2. The lithium-carbon monofluoride cell of claim 1 wherein: Both the positive electrode tab and the negative electrode tab are located on the same side of the aluminum-plastic film shell; in the battery cell, each positive electrode tab is connected to the positive electrode tab by ultrasonic welding, and each negative electrode tab is connected to the negative electrode tab by ultrasonic welding.

3. The lithium-carbon monofluoride battery according to any one of claims 1-2, wherein: The positive electrode external tab is made of aluminum, the negative electrode external tab is made of nickel-plated copper, the negative electrode sheet is made of lithium, and the diaphragm is a cellulose diaphragm. The thickness of the positive electrode slurry layer is 167~193μm.

4. The lithium-carbon monofluoride cell of claim 3 wherein: The material of the negative electrode external tab is nickel-plated copper with a nickel plating layer thickness of 1±0.05μm; On the positive electrode sheet, the spacing between adjacent through holes is 5~7mm, and the diameter of the through holes is 0.5±0.05mm; Both the positive electrode external tab and the negative electrode external tab are located on the same edge of the aluminum-plastic film shell; The thickness of the aluminum-plastic film shell is 70~160 micrometers, and the distance between each side of the aluminum-plastic film shell and each side of the battery cell is 0.5~1.0 mm.

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