A phosphorus-based porous carbon composite material, a preparation method thereof and a negative electrode and a lithium ion battery

Abstract

The application provides a phosphorus-based porous carbon composite material, a preparation method thereof and a negative electrode and a lithium ion battery, and the preparation method comprises the following steps: S1: etching treatment of a biomass carbon source by using an acidic etchant to obtain a precursor; S2: first heat treatment of the precursor to obtain a porous carbon material; the temperature of the first heat treatment is 600-1000 DEG C; S3: second heat treatment of the porous carbon material and red phosphorus to obtain a phosphorus-based porous carbon composite material; the temperature of the second heat treatment is 460-800 DEG C. The preparation method of the phosphorus-based porous carbon composite material provided by the application uses biomass as a carbon source to prepare a porous carbon material with a specific pore structure, and effectively anchors red phosphorus on the obtained porous carbon material, and under the synergistic action of the two, the lithium ion battery prepared subsequently from the phosphorus-based porous carbon composite material has a high discharge specific capacity and excellent long-term fast charging stability.

Description

Technical Field

[0001] This invention relates to a phosphorus-based porous carbon composite material, its preparation method, and its negative electrode and lithium-ion battery. Background Technology

[0002] Phosphorus (P) has attracted widespread attention as an anode material for lithium-ion batteries (LIBs) due to its high theoretical specific capacity (2595 mAh / g) and safe operating potential (0.75 V). Among the phosphorus allotropes red phosphorus (RP), white phosphorus (WP), black phosphorus (BR), and purple phosphorus (VR), RP is more suitable as an anode material for lithium batteries due to its low commercialization cost, abundant resources, ease of processing, and chemical stability at room temperature. However, the large volume expansion (approximately 300% in lithium batteries) and poor conductivity (10⁻⁶ ppm) during cycling of red phosphorus are still a concern. -4 To address the issue of S / cm (solar conductivity), combining reactive oxidants (RP) with highly conductive carbon matrices (carbon black, carbon nanotubes, graphene, porous carbon) is considered an effective approach. Among these matrices, porous carbon materials are attracting increasing attention due to their advantages of providing sufficient space to load RP and high conductivity.

[0003] However, most porous carbon materials have relatively simple configurations, which easily leads to the shedding and aggregation of RP in the internal space, hindering Li + Diffusion can lead to underutilization of active materials, and can also cause sudden capacity decay and slow electrochemical reaction kinetics, hindering the large-scale application of phosphorus-carbon composite materials in lithium-ion battery anode materials. Summary of the Invention

[0004] To address the aforementioned deficiencies in existing technologies, this invention provides a phosphorus-based porous carbon composite material, its preparation method, an anode, and a lithium-ion battery. The preparation method of the phosphorus-based porous carbon composite material provided by this invention uses biomass as a carbon source to prepare a porous carbon material with a specific pore structure, and effectively anchors red phosphorus onto the prepared porous carbon material. Through the synergistic effect of these two methods, the lithium-ion battery prepared using the phosphorus-based porous carbon composite material of this invention exhibits high discharge specific capacity and excellent long-term fast-charging stability.

[0005] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0006] This invention provides a method for preparing a phosphorus-based porous carbon composite material, which includes the following steps:

[0007] S1: The biomass carbon source is etched using an acidic etchant to obtain the precursor;

[0008] S2: The precursor is subjected to a first heat treatment to obtain a porous carbon material;

[0009] The temperature of the first heat treatment is 600–1000℃;

[0010] S3: The porous carbon material is subjected to a second heat treatment with red phosphorus to obtain a phosphorus-based porous carbon composite material.

[0011] The temperature of the second heat treatment is 460–800°C.

[0012] In some preferred embodiments, in step S1, the biomass carbon source includes one or more of longan kernels, papaya seed kernels, apple kernels, and cherry kernels, such as longan kernels or papaya seed kernels.

[0013] In some preferred embodiments, step S1 includes a pretreatment operation before the etching process.

[0014] In some preferred embodiments, in step S1, the pretreatment operation involves pulverizing and refining the dried biomass carbon source and passing it through a 100-mesh sieve to obtain the sieved material.

[0015] In the above scheme, the pulverization and refining are preferably carried out using a traditional Chinese medicine pulverizer.

[0016] In the above scheme, the drying temperature is preferably 100-120°C, for example, 110°C; and the drying time is preferably 8-16 hours, for example, 12 hours.

[0017] In some preferred embodiments, in step S1, the etching process involves immersing the biomass carbon source in an acidic etchant.

[0018] In the above scheme, the acidic etchant preferably includes one or more of hydrochloric acid and sulfuric acid, such as 0.5M HCl solution or 0.4M H2SO4.

[0019] In the above scheme, the etching process is preferably carried out under stirring; the stirring time is preferably 15 to 25 hours, for example, 20 hours.

[0020] In some preferred embodiments, in step S2, the first heat treatment is performed under an inert atmosphere, such as nitrogen and / or argon.

[0021] In some preferred embodiments, in step S2, the heating rate of the first heat treatment is 3 to 5 °C / min.

[0022] In some preferred embodiments, in step S2, the temperature of the first heat treatment is 600–800°C.

[0023] In some preferred embodiments, in step S2, the duration of the first heat treatment is 2 to 4 hours. The duration of the first heat treatment is the time spent holding at the temperature specified in the first heat treatment.

[0024] In some preferred embodiments, step S2 further includes grinding, washing, and drying operations after the first heat treatment.

[0025] In the above scheme, the grinding operation is preferably to grind the material after the first heat treatment into powder with a particle size of 10-20μm; the grinding operation is preferably carried out by one or more of a jaw crusher, a double roll crusher and an air jet mill, and more preferably by sequentially using a jaw crusher, a double roll crusher and an air jet mill.

[0026] In the above scheme, the washing operation is preferably carried out using clean water.

[0027] In the above scheme, the drying temperature is preferably 100-120°C, for example, 110°C; the drying time is preferably 2-6 hours, for example, 4 hours.

[0028] In some preferred embodiments, in step S3, the red phosphorus is micron-sized red phosphorus, preferably red phosphorus with a particle size range of 5 to 50 μm.

[0029] In some preferred embodiments, in step S3, the mass ratio of the porous carbon material to the red phosphorus is 1:(1 to 1.1), for example, 1:1.

[0030] In some preferred embodiments, in step S3, the second heat treatment is performed in a vacuum vessel.

[0031] In some preferred embodiments, in step S3, the second heat treatment is performed under an inert atmosphere, such as nitrogen and / or argon.

[0032] In some preferred embodiments, in step S3, the heating rate of the second heat treatment is 3 to 5 °C / min, for example, 4 °C / min.

[0033] In some preferred embodiments, in step S3, the temperature of the second heat treatment is 500-650°C, for example, 600°C.

[0034] In some preferred embodiments, in step S3, the second heat treatment time is 2 to 4 hours. The second heat treatment time is the time during which the temperature is maintained at the second heat treatment temperature.

[0035] In some preferred embodiments, step S3 further includes cooling, washing, and drying operations after the second heat treatment.

[0036] In the above scheme, the cooling operation is preferably to cool the material after the second heat treatment to 240-260°C and then keep it at that temperature for 18-30 hours, more preferably to cool it to 240°C and then keep it at that temperature for 24 hours, and finally cool it down to room temperature.

[0037] In the above scheme, the washing operation is preferably performed using CS2.

[0038] In the above scheme, the drying temperature is preferably 100-120°C, for example, 110°C; and the drying time is preferably 2-4 hours.

[0039] This invention provides a phosphorus-based porous carbon composite material, which is prepared by the phosphorus-based porous carbon composite material preparation method described above.

[0040] This invention provides a phosphorus-based porous carbon composite material, which includes a porous carbon material and phosphorus deposited inside the pores of the porous carbon material;

[0041] The porous carbon material has an average particle size of 10–20 μm and a specific surface area of ​​1300–1500 m². 2 / g;

[0042] The porous carbon material has a microporosity of 70%–80% and a micropore volume of 0.4–0.6 cm³. 3 / g; the average pore size of the porous carbon material is 0.35–0.5 nm;

[0043] The mesoporous carbon material has a mesoporous ratio of 20% to 30% and a mesopore volume of 0.1 to 0.2 cm³. 3 / g; the average pore size of the mesopores in the porous carbon material is 3-4.5 nm;

[0044] The porous carbon material accounts for 50% to 60% of the mass percentage of the phosphorus-based porous carbon composite material; the phosphorus accounts for 40% to 50% of the mass percentage of the phosphorus-based porous carbon composite material.

[0045] In some preferred embodiments, the porous carbon material has an average particle size of 18 μm.

[0046] In some preferred embodiments, the porous carbon material has a specific surface area of ​​1358 m². 2 / g or 1477m 2 / g.

[0047] In some preferred embodiments, the microporosity of the porous carbon material is 76.30% or 77.23%.

[0048] In some preferred embodiments, the micropore volume of the porous carbon material is 0.512 cm³. 3 / g or 0.519cm 3 / g.

[0049] In some preferred embodiments, the average pore size of the porous carbon material is 0.4 nm or 0.44 nm.

[0050] In some preferred embodiments, the mesoporous content of the porous carbon material is 22.77% or 23.70%.

[0051] In some preferred embodiments, the mesopore volume of the porous carbon material is 0.153 cm³. 3 / g or 0.159cm 3 / g.

[0052] In some preferred embodiments, the average pore size of the porous carbon material is 3.45 nm or 4.2 nm.

[0053] In some preferred embodiments, the porous carbon material accounts for 54% or 57% of the mass percentage of the phosphorus-based porous carbon composite material.

[0054] In some preferred embodiments, the phosphorus accounts for 43% or 46% of the mass percentage of the phosphorus-based porous carbon composite material.

[0055] In this invention, pores with a diameter less than 2 nm are called micropores; pores with a diameter between 2 and 50 nm are called mesopores (or medium pores); and pores with a diameter greater than 50 nm are called macropores.

[0056] The present invention also provides a negative electrode, which is a phosphorus-based porous carbon composite material as described above.

[0057] The present invention also provides a lithium-ion battery comprising a negative electrode as described above.

[0058] This invention utilizes biodegradable biowaste to prepare oxygen-self-doped hierarchical porous carbon materials, which are then used as carriers for phosphoric acid (RP). Through a vapor-condensation method, RP is converted into phosphoric acid (WP) vapor. The WP vapor diffuses and fills the pores of the porous carbon material, primarily the micropores, under the influence of capillary force and pressure difference. After cooling, it transforms into nanoscale red phosphorus (NRP, a tetrahedral P4 molecule with a side length of 0.221 nm at 600℃) and is anchored in the micropores through spatial confinement, resulting in a phosphorus-based porous carbon composite material. The micropores effectively buffer the volume expansion of RP during cycling; the mesopores provide sufficient space for the electrolyte, promoting the formation of phosphorus-based porous carbon composites.+ The diffusion of carbon; at the same time, the high conductivity of carbon itself is beneficial to the rapid transport of electrons, thereby improving the fast charging performance of lithium-ion batteries, giving them a high discharge specific capacity and excellent long-term fast charging stability, thus making them highly commercially viable.

[0059] Based on common knowledge in the field, the above-mentioned preferred conditions can be combined arbitrarily to obtain various preferred embodiments of the present invention.

[0060] The reagents and raw materials used in this invention are all commercially available.

[0061] The positive and progressive effects of this invention are as follows:

[0062] (1) The phosphorus-based porous carbon composite material prepared by the present invention has a richer pore structure, which can reduce the volume change of active material RP during subsequent battery cycling and prevent its shedding and aggregation, effectively increasing the utilization rate and cycle stability of RP, greatly improving the fast charging stability of lithium-ion batteries, and optimizing the application of phosphorus-carbon composite material in lithium-ion batteries.

[0063] (2) The method for preparing phosphorus-based porous carbon composite material provided by the present invention uses biomass as a carbon source to prepare porous carbon material with a specific pore structure, and effectively anchors red phosphorus on the obtained porous carbon material. Under the synergistic effect of the two, the lithium-ion battery prepared by the phosphorus-based porous carbon composite material of the present invention has a high discharge specific capacity and excellent long-term fast charging stability. Moreover, the method is low in cost and simple in process, which not only realizes the reuse of waste resources, but also has good commercial prospects. Attached Figure Description

[0064] Figure 1 The image shows a SEM image of the phosphorus-based porous carbon composite material prepared in Example 1.

[0065] Figure 2 The image shows the XRD pattern of the phosphorus-based porous carbon composite material prepared in Example 1.

[0066] Figure 3 The charge-discharge curves of the lithium-ion battery prepared using the phosphorus-based porous carbon composite material prepared in Example 1 as the negative electrode material are shown for the first, second, and 200th cycles. Detailed Implementation

[0067] The present invention is further illustrated below by way of embodiments, but the invention is not limited to the scope of the embodiments described herein. Experimental methods in the following embodiments that do not specify specific conditions were performed according to conventional methods and conditions, or as selected according to the product instructions.

[0068] In the embodiments and comparative examples of this invention, longan seeds or papaya seeds can be obtained by conventional methods through peeling and pulp removal; commercial micron-sized red phosphorus was purchased from Aladdin Reagent (Shanghai) Co., Ltd., with a particle size range of 5-50 μm.

[0069] Example 1

[0070] S1: Take 1000g of longan seeds dried at 110℃ for 12h, grind them into fine powder using a traditional Chinese medicine pulverizer, pass them through a 100-mesh sieve, and then perform etching treatment, that is, soak the sieve in 5L of 0.5M HCl solution and stir for 20h to obtain the precursor.

[0071] S2: The precursor is subjected to a first heat treatment under the following conditions: nitrogen atmosphere, heating rate of 5℃ / min, and holding at 800℃ for 2h; then, the material after the first heat treatment is ground into powder with a particle size of 10-20μm by a jaw crusher, a double roll crusher and an air jet mill in sequence, washed with water and dried at 110℃ for 4h to obtain porous carbon material;

[0072] S3: 200g of commercial micron-sized red phosphorus and 200g of the above porous carbon material were uniformly mixed and placed in a vacuum autoclave for a second heat treatment. The specific conditions were: nitrogen atmosphere, heating rate of 4℃ / min, holding at 500℃ for 2h, then cooling to 240℃ and holding for 24h, and finally cooling to room temperature. The residual white phosphorus in the material was then washed away with CS2 and dried at 110℃ for 2h to obtain phosphorus-based porous carbon composite material.

[0073] Example 2

[0074] S1: Take 1000g of papaya seeds dried at 110℃ for 12h, grind them into fine powder using a traditional Chinese medicine pulverizer, pass them through a 100-mesh sieve, and then perform etching treatment by soaking the sieve in 5L of 0.5M HCl solution and stirring for 20h to obtain the precursor.

[0075] S2: The precursor is subjected to a first heat treatment under the following conditions: argon atmosphere, heating rate of 3℃ / min, and holding at 600℃ for 2h; then, the material after the first heat treatment is ground into powder with a particle size of 10-20μm by a jaw crusher, a double roll crusher and an air jet mill in sequence, washed with water and dried at 110℃ for 4h to obtain porous carbon material;

[0076] S3: 200g of commercial micron-sized red phosphorus and 200g of the above porous carbon material were uniformly mixed and placed in a vacuum autoclave for a second heat treatment. The specific conditions were: argon atmosphere, heating rate of 4℃ / min, holding at 600℃ for 2h, then cooling to 240℃ and holding for 24h, and finally cooling to room temperature. The residual white phosphorus in the material was then washed away with CS2 and dried at 110℃ for 2h to obtain phosphorus-based porous carbon composite material.

[0077] Comparative Example 1

[0078] 200g of commercial micron-sized red phosphorus and 200g of commercial porous carbon material (model CMK-3) were uniformly mixed and placed in a vacuum autoclave for heat treatment. The specific conditions were: argon atmosphere, heating rate of 4℃ / min, holding at 600℃ for 2h, then cooling to 240℃ and holding for 24h, and finally cooling to room temperature. The residual white phosphorus in the material was then washed away with CS2 and dried at 110℃ for 2h to obtain phosphorus-based porous carbon composite material.

[0079] Comparative Example 2

[0080] Commercially available micron-sized red phosphorus is used directly as the anode material.

[0081] Example 1

[0082] Characterization of the properties of phosphorus-based porous carbon composites

[0083] (1) Test method

[0084] The average particle size, specific surface area, microporosity, micropore volume, average micropore diameter, mesoporosity, mesopore volume, and average mesopore diameter of the porous carbon materials in the above examples and comparative examples were characterized using an Autosorb iQ-3 fully automatic specific surface area and pore size analyzer.

[0085] The microstructure of the phosphorus-based porous carbon composite materials of the above-described embodiments and comparative examples was observed using a JSM-7500F scanning electron microscope. The crystal structure and phase composition of the phosphorus-based porous carbon composite materials of the above-described embodiments and comparative examples were analyzed using a Bruker D8 X-ray diffractometer, with Cu Kα as the radiation source. The scanning range was 10–80°, and the scanning speed was 10° / min.

[0086] (2) Test Results

[0087] The test results are shown in Tables 1 and 2.

[0088] Table 1

[0089]

[0090] Table 2

[0091]

[0092] As shown in Table 1, the porous carbon material in the phosphorus-based porous carbon composite material prepared in this application has a high microporosity and a low mesoporosity, and there are no macropores. In contrast, the conventional porous carbon material used in Comparative Example 1 has a mesoporosity as high as 91.10%, with almost no micropores. Figure 1SEM image of the phosphorus-based porous carbon composite material prepared in Example 1; Figure 2 The image shows the XRD pattern of the phosphorus-based porous carbon composite material prepared in Example 1. Figure 2 It can be seen that the spectrum only shows a broad peak at 2θ≈23°, which can be attributed to the characteristic peak of amorphous carbon. The peak of RP was not observed, which indicates that RP has been successfully loaded into the pores of the phosphorus-based porous carbon composite material in the form of nanoparticles, mainly in the micropores. Therefore, the characteristic peak of RP was not shown.

[0093] Example 2

[0094] Electrochemical performance testing of lithium-ion batteries prepared from phosphorus-based porous carbon composite materials

[0095] (1) Test method

[0096] The product obtained in the examples or comparative examples was used as the negative electrode material (80 wt%), mixed with conductive carbon black (10 wt%) and polyvinylidene fluoride (10 wt%) binder, dissolved in NMP to form a homogeneous slurry, and the slurry was coated on copper foil and vacuum dried at 60°C for 10 h to obtain the negative electrode. The mass loading of the electrode was approximately 1.5 mg / cm³. 2 Lithium metal sheet is used as the counter electrode, 1M LiPF6 dissolved in a mixture of EC and DEC (1:1 = v:v) is used as the electrolyte, and a 2500 type PP membrane is used as the separator. The coin cell (type 2025) is assembled in a glove box (Ar atmosphere).

[0097] Constant current charge-discharge tests were performed using a LAND tester. The test conditions were room temperature, voltage range of 0.01–2.5V, and current density of 1A / g.

[0098] (2) Test Results

[0099] The test results are shown in Table 3.

[0100] Table 3

[0101]

[0102] Comparing the electrical performance of lithium-ion batteries obtained from Examples 1 and 2 with Comparative Example 1, it was found that the discharge specific capacity and capacity retention of the battery prepared by the phosphorus-based porous carbon composite material of the present invention were significantly higher than those of Comparative Example 1. Comparative Example 2 used pure red phosphorus as the negative electrode material for lithium-ion batteries. Red phosphorus has a theoretical specific capacity as high as 2595 mAh / g, but due to the lack of carbon skeleton support, it will produce huge volume expansion during cycling, and will also pulverize and fall off after cycling, resulting in a rapid decrease in capacity and extremely low capacity retention. The capacity exhibited in subsequent cycles should be attributed to the carbon capacity contribution of the conductive agent. Therefore, the phosphorus-based porous carbon composite material prepared by the present invention has good application prospects and high market value in improving battery capacity and cycle stability.

Claims

1. A method for preparing a phosphorus-based porous carbon composite material, characterized in that, It includes the following steps: S1: The biomass carbon source is etched using an acidic etchant to obtain the precursor; The biomass carbon source includes one or more of longan seeds, papaya seeds, apple seeds, and cherry seeds; the acidic etching agent includes one or more of hydrochloric acid and sulfuric acid. S2: The precursor is subjected to a first heat treatment to obtain a porous carbon material; The temperature of the first heat treatment is 600~1000℃; the heating rate of the first heat treatment is 3~5℃ / min; S3: Mix the porous carbon material with red phosphorus and perform a second heat treatment to obtain a phosphorus-based porous carbon composite material. The mass ratio of the porous carbon material to the red phosphorus is 1:(1~1.1); the temperature of the second heat treatment is 460~650℃.

2. The method for preparing the phosphorus-based porous carbon composite material as described in claim 1, characterized in that, It meets one or more of the following conditions: (1) In step S1, the biomass carbon source includes longan kernel or papaya seed kernel; (2) In step S1, a pretreatment operation is also included before the etching process. The pretreatment operation is to crush the dried biomass carbon source into fine powder and pass it through a 100-mesh sieve to obtain the sieve product. (3) In step S1, the etching process involves immersing the biomass carbon source in an acidic etching agent; The acidic etching agent is a 0.5 M HCl solution or a 0.4 M H2SO4 solution.

3. The method for preparing the phosphorus-based porous carbon composite material as described in claim 2, characterized in that, It meets one or more of the following conditions: (1) The pulverization and refining are carried out using a traditional Chinese medicine pulverizer; (2) The drying temperature is 100~120℃; (3) The drying time is 8~16 h; (4) The etching process is carried out under stirring for 15-25 h.

4. The method for preparing the phosphorus-based porous carbon composite material as described in claim 3, characterized in that, The drying temperature is 110°C; And / or, the drying time is 12 h; And / or, the stirring time is 20 h.

5. The method for preparing the phosphorus-based porous carbon composite material as described in claim 1, characterized in that, It meets one or more of the following conditions: (1) In step S2, the first heat treatment is carried out under an inert atmosphere; (2) In step S2, the temperature of the first heat treatment is 600~800℃; (3) In step S2, the duration of the first heat treatment is 2-4 h; (4) In step S2, after the first heat treatment, the process also includes grinding, washing and drying.

6. The method for preparing the phosphorus-based porous carbon composite material as described in claim 5, characterized in that, It meets one or more of the following conditions: (1) In step S2, the first heat treatment is performed under nitrogen and / or argon; (2) In step S2, the grinding operation is to grind the material after the first heat treatment into powder with a particle size of 10~20 μm; (3) In step S2, the grinding operation is carried out using one or more of a jaw crusher, a double roll crusher, and an air jet mill; (4) The washing operation is carried out using clean water; (5) The drying temperature is 100~120℃; (6) The drying time is 2 to 6 hours.

7. The method for preparing the phosphorus-based porous carbon composite material as described in claim 6, characterized in that, The grinding operation is carried out sequentially using a jaw crusher, a double roll crusher, and an air jet mill. And / or, the drying temperature is 110°C; And / or, the drying time is 4 hours.

8. The method for preparing the phosphorus-based porous carbon composite material as described in claim 1, characterized in that, It meets one or more of the following conditions: (1) In step S3, the red phosphorus is micron-sized red phosphorus; (2) In step S3, the mass ratio of the porous carbon material to the red phosphorus is 1:1; (3) In step S3, the second heat treatment is carried out in a vacuum reactor; (4) In step S3, the second heat treatment is carried out under an inert atmosphere; (5) In step S3, the heating rate of the second heat treatment is 3~5℃ / min; (6) In step S3, the temperature of the second heat treatment is 500~650℃; (7) In step S3, the second heat treatment time is 2~4 h.

9. The method for preparing the phosphorus-based porous carbon composite material as described in claim 8, characterized in that, It meets one or more of the following conditions: (1) In step S3, the red phosphorus is red phosphorus with a particle size range of 5~50 μm; (2) In step S3, the second heat treatment is performed under nitrogen and / or argon; (3) In step S3, the heating rate of the second heat treatment is 4℃ / min; (4) In step S3, the temperature of the second heat treatment is 600°C.

10. The method for preparing the phosphorus-based porous carbon composite material as described in claim 8, characterized in that, Step S3, after the second heat treatment, also includes cooling, washing and drying operations.

11. The method for preparing the phosphorus-based porous carbon composite material as described in claim 10, characterized in that, It meets one or more of the following conditions: (1) The cooling operation is to cool the material after the second heat treatment to 240~260℃ and then keep it at that temperature for 18~30h; (2) The washing operation is performed using CS2; (3) The drying temperature is 100~120℃; (4) The drying time is 2 to 4 hours.

12. The method for preparing the phosphorus-based porous carbon composite material as described in claim 11, characterized in that, The cooling process involves cooling the temperature to 240°C, maintaining the temperature for 24 hours, and finally cooling it down to room temperature. And / or, the drying temperature is 110°C.

13. A phosphorus-based porous carbon composite material, characterized in that, It is prepared by the method of any one of claims 1 to 12 for preparing phosphorus-based porous carbon composite materials.

14. A phosphorus-based porous carbon composite material, characterized in that, The phosphorus-based porous carbon composite material includes porous carbon material and phosphorus deposited inside the pores of the porous carbon material; The porous carbon material has an average particle size of 10-20 μm and a specific surface area of ​​1300-1500 m². 2 / g; The porous carbon material has a microporosity of 70%~80% and a micropore volume of 0.4~0.6 cm³. 3 / g; the average pore size of the porous carbon material is 0.35~0.5 nm; The mesoporous carbon material has a mesoporous ratio of 20% to 30% and a mesopore volume of 0.1 to 0.2 cm³. 3 / g; the average pore size of the mesopores in the porous carbon material is 3~4.5 nm; The porous carbon material accounts for 50% to 60% of the mass of the phosphorus-based porous carbon composite material; the phosphorus accounts for 40% to 50% of the mass of the phosphorus-based porous carbon composite material.

15. The phosphorus-based porous carbon composite material as described in claim 14, characterized in that, The phosphorus-based porous carbon composite material satisfies one or more of the following conditions: (1) The average particle size of the porous carbon material is 18 μm; (2) The specific surface area of ​​the porous carbon material is 1358 m². 2 / g or 1477 m 2 / g; (3) The microporosity of the porous carbon material is 76.30% or 77.23%; (4) The micropore volume of the porous carbon material is 0.512 cm³. 3 / g or 0.519 cm 3 / g; (5) The average pore size of the micropores in the porous carbon material is 0.4 nm or 0.44 nm; (6) The mesoporous rate of the porous carbon material is 22.77% or 23.70%; (7) The mesopore volume of the porous carbon material is 0.153 cm³. 3 / g or 0.159 cm 3 / g; (8) The average pore size of the mesopores in the porous carbon material is 3.45 nm or 4.2 nm; (9) The porous carbon material accounts for 54% or 57% of the mass of the phosphorus-based porous carbon composite material; (10) The phosphorus accounts for 43% or 46% of the mass of the phosphorus-based porous carbon composite material.

16. A negative electrode, characterized in that, It includes phosphorus-based porous carbon composite materials as described in any one of claims 13 to 15.

17. A lithium-ion battery, characterized in that, It includes the negative electrode as described in claim 16.

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