Conductive powder and preparation method thereof

Abstract

The present invention belongs to the technical field of composite materials and particularly relates to a conductive powder and a preparation method thereof. The raw materials for preparing the conductive powder comprise the following components: 5-50 parts of graphite, 80-120 parts of a copper salt, 50-100 parts of a complexing agent, 20-80 parts of an acidic compound, 100-200 parts of a nickel salt, and 10-30 parts of a reducing agent. The conductive powder prepared by the present invention has low resistivity and high electromagnetic shielding properties. In the preparation method of the conductive powder of the present invention, nickel is coated on the surface of copper, thereby overcoming the oxidation problem of copper in the natural environment. The conductive powder prepared by the method of the present invention has high stability. The particle size of the conductive powder prepared by the method of the present invention can be selected.

Description

Technical Field

[0001] The invention belongs to the technical field of composite materials, and particularly relates to conductive powder and a preparation method thereof. Background Art

[0002] Traditional conductive powders include electrolytic nickel powder, atomized nickel powder, nickel-coated copper powder and other conductive powders. With the development of 5G technology, 5G technology has gradually matured, and the application requirements of conductive powders have been continuously improved. Traditional conductive powders can no longer meet the current technical requirements of 5G technology for conductive materials. The requirements for resistivity and electromagnetic shielding performance are getting higher and higher.

[0003] Chinese patent CN201410246298.4 discloses a copper composite conductive powder coated with a carbon layer of a graphene structure and a preparation method thereof. The powder needs to react at a high temperature above 100°C. The resistance of the conductive powder reaches several hundred ohms, which does not meet the application requirements of the conductive powder in 5G technology.

[0004] The preparation of a conductive powder with low resistance and high electromagnetic shielding performance is a technical problem that needs to be solved at present. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides a conductive powder, the raw materials of which include the following components, by weight: 5-50 parts of graphite, 80-120 parts of copper salt, 50-100 parts of complexing agent, 20-80 parts of acidic compound, 100-200 parts of nickel salt, and 10-30 parts of reducing agent.

[0006] Preferably, the graphite is selected from one or more of block graphite, flake graphite, and cryptocrystalline graphite.

[0007] Furthermore, the graphite is flake graphite.

[0008] Preferably, the weight ratio of the complexing agent to the copper salt is 1:(0.8-1.5).

[0009] Preferably, the weight ratio of the complexing agent to the copper salt is 1:(1-1.3).

[0010] Furthermore, the copper salt is selected from one or more of basic copper carbonate, copper chloride, basic copper sulfate, copper nitrate, copper sulfate, and copper carbonate.

[0011] Preferably, the complexing agent is selected from one or more of sodium hydroxyethylidene diphosphate, potassium sodium tartrate, and sodium ethylenediaminetetramethylenephosphate.

[0012] Preferably, the acidic compound is a hydroxy acid or an amino acid.

[0013] Furthermore, the hydroxy acid is selected from dibasic hydroxy acids.

[0014] Preferably, the raw materials further include inorganic salts, complexing agents, and plasticizers.

[0015] Furthermore, the inorganic salt is selected from one or more of calcium salt, potassium salt, sodium salt, chloride salt and magnesium salt.

[0016] A second aspect of the present invention provides a method for preparing a conductive powder, comprising the following steps:

[0017] S1. calcined graphite, and after cooling, spherical graphite was obtained using a graphite briquetting machine;

[0018] S2. Water and a complexing agent are added to the reactor;

[0019] S3. The acidic compound is added to the reactor with stirring, and an inorganic salt is added with stirring;

[0020] S4. The copper salt and spherical graphite were added to the reactor and stirred, and then a reducing agent was added and stirred;

[0021] S5. The complexing agent, plasticizer, nickel salt are added to the reactor, and then a reducing agent is added and stirred;

[0022] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0023] Preferably, the D50 particle size of the spherical graphite in S1 is 0.5-50 μm.

[0024] Furthermore, the D50 particle size of the spherical graphite in S1 is 2-30 μm.

[0025] Beneficial effects

[0026] 1. The conductive powder prepared by the present invention has low resistivity and high electromagnetic shielding property.

[0027] 2. In the preparation method of the conductive powder of the present invention, nickel is coated on the surface of copper, which overcomes the oxidation problem of copper in the natural environment.

[0028] 3. The conductive powder prepared by the method of the present invention has high stability.

[0029] 4. The particle size of the conductive powder prepared by the method of the present invention can be selected. DETAILED DESCRIPTION

[0030] The following is a further clear and complete description of the technical features of the technical solution provided by the present invention in conjunction with specific implementation methods, which does not limit the scope of protection thereof.

[0031] The terms "preferred," "more preferred," and the like, used herein refer to embodiments of the present invention that may provide certain benefits under certain circumstances. However, other embodiments may also be preferred under the same or other circumstances. Furthermore, the recitation of one or more preferred embodiments does not imply that other embodiments are not useful, nor is it intended to exclude other embodiments from the scope of the present invention.

[0032] A conductive powder comprises the following raw materials in parts by weight: 5-50 parts of graphite, 80-120 parts of copper salt, 50-100 parts of complexing agent, 20-80 parts of acidic compound, 100-200 parts of nickel salt and 10-30 parts of reducing agent.

[0033] In one embodiment, the graphite is selected from one or more of bulk graphite, flake graphite, and cryptocrystalline graphite.

[0034] In a preferred embodiment, the graphite is flake graphite.

[0035] In one embodiment, the weight ratio of the complexing agent to the copper salt is 1:(0.8-1.5).

[0036] In one embodiment, the weight ratio of the complexing agent to the copper salt is 1:(1-1.3).

[0037] In a more preferred embodiment, the weight ratio of the complexing agent to the copper salt is 1:1.25.

[0038] The inventors of the present application unexpectedly discovered in experiments that when the weight ratio of the complexing agent to the copper salt is 1: (0.8-1.5), the deposition rate and deposition effect of copper in the copper plating solution on the surface of the graphite ball are relatively good, the copper plating layer is uniform, and the resistance value of the conductive powder is low.

[0039] In one embodiment, the copper salt is selected from one or more of basic copper carbonate, copper chloride, basic copper sulfate, copper nitrate, copper sulfate, and copper carbonate.

[0040] In one embodiment, the complexing agent is selected from one or more of sodium hydroxyethylidene diphosphate, potassium sodium tartrate, and sodium ethylenediaminetetramethylenephosphate.

[0041] In one embodiment, the acidic compound is a hydroxy acid or an amino acid.

[0042] In a preferred embodiment, the hydroxy acid is selected from dibasic hydroxy acids.

[0043] In a more preferred embodiment, the dihydroxy acid is selected from one or more of malic acid, citric acid, and tartaric acid.

[0044] In one embodiment, the nickel salt is selected from one or more of nickel acetate, nickel sulfate, and nickelous sulfate.

[0045] In one embodiment, the reducing agent is a nitrogen-containing compound.

[0046] In a preferred embodiment, the nitrogen-containing compound is ammonia or hydrazine.

[0047] In one embodiment, the raw materials further include 0.01-0.5 parts of inorganic salt, 1-10 parts of complexing agent, and 50-200 ml of plasticizer.

[0048] In one embodiment, the inorganic salt is selected from one or more of calcium salt, potassium salt, sodium salt, chloride salt, and magnesium salt.

[0049] In one embodiment, the sodium salt is selected from one or more of sodium chloride, sodium sulfate, sodium thiosulfate, sodium carbonate, sodium bicarbonate, sodium fluoride, and sodium nitrate.

[0050] In one embodiment, the complexing agent is selected from one or more of thiourea, sodium bisulfite, and sodium sulfide.

[0051] In one embodiment, the plasticizer is selected from phthalate compounds, phosphate compounds, and fatty acid compounds.

[0052] In one embodiment, the phthalate compound is selected from one or more of dioctyl phthalate, di(2-ethylhexyl) phthalate, dibutyl phthalate, tolyl butyl phthalate, diethyl phthalate, dipropyl phthalate, diisopropyl phthalate, diisobutyl phthalate, dipentyl phthalate, di-n-octyl phthalate, diisononyl phthalate, diisodecyl phthalate, dimethyl phthalate, dihexyl phthalate, dicyclohexyl phthalate, diisooctyl phthalate, and di-n-nonyl phthalate.

[0053] A second aspect of the present invention provides a method for preparing a conductive powder, comprising the following steps:

[0054] S1. calcined graphite, and after cooling, spherical graphite was obtained using a graphite briquetting machine;

[0055] S2. Water and a complexing agent are added to the reactor;

[0056] S3. The acidic compound is added to the reactor with stirring, and an inorganic salt is added with stirring;

[0057] S4. The copper salt and spherical graphite were added to the reactor and stirred, and then a reducing agent was added and stirred;

[0058] S5. The complexing agent, plasticizer, nickel salt are added to the reactor, and then a reducing agent is added and stirred;

[0059] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0060] In one embodiment, the D50 particle size of the spherical graphite in S1 is 0.5-50 μm.

[0061] In one embodiment, the D50 particle size of the spherical graphite in S1 is 2-30 μm.

[0062] In a preferred embodiment, the D50 particle size of the spherical graphite in S1 is 5-20 μm.

[0063] In a more preferred embodiment, the D50 particle size of the spherical graphite in S1 is 10 μm.

[0064] In one embodiment, the method for preparing the conductive powder comprises the following steps:

[0065] S1. calcining graphite at a calcination temperature of 1500-5000 ℃, and after cooling, using a graphite briquetting machine to obtain spherical graphite;

[0066] S2. Add water to the reactor, raise the temperature to 60-70 ° C, add the complexing agent and stir to melt;

[0067] S3. The acidic compound is added to the reactor and stirred for 1-20 min, and an inorganic salt is added and stirred for 1-20 min;

[0068] S4. The reactor temperature was raised to 65-75 ° C, copper salt, spherical graphite was added and stirred, and the nitrogen-containing compound was added to the solution and stirred for 0.1-5h;

[0069] S5. The complexing agent, plasticizer, nickel salt are added to the reactor, the temperature is raised to 70-80 ° C, and the nitrogen-containing compound is added to the solution and stirred for 0.1-5h;

[0070] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0071] In one embodiment, the D50 particle size of the spherical graphite in S1 is 0.5-50 μm.

[0072] In one embodiment, the D50 particle size of the spherical graphite in S1 is 2-30 μm.

[0073] In a preferred embodiment, the D50 particle size of the spherical graphite in S1 is 5-20 μm.

[0074] In a more preferred embodiment, the D50 particle size of the spherical graphite in S1 is 10 μm.

[0075] The inventors of this application found that by subjecting flake graphite to a curve combustion, the calcination temperature is raised from room temperature to 1500°C, kept constant for 2 hours, then raised to 5000°C, kept constant for 2 hours, and then cooled to room temperature. Graphite balls can be prepared using a graphite ball press, and the particle size of the graphite balls can be controlled.

[0076] Example

[0077] Example 1

[0078] A conductive powder comprises the following raw materials, measured by weight: 20 parts of graphite, 100 parts of copper sulfate, 80 parts of potassium sodium tartrate, 30 parts of citric acid, 10 parts of malic acid, 0.2 parts of sodium fluoride, 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate, and 20 parts of hydrazine.

[0079] A method for preparing conductive powder comprises the following steps:

[0080] S1. High temperature calcination of flake graphite, the calcination temperature is from room temperature to 1500 ℃, constant temperature 2h, then heated to 5000 ℃, constant temperature 2h, cooled to room temperature, and after cooling, spherical graphite is obtained by graphite ball press machine;

[0081] S2. The reactor was added with 1000g of water, heated to 65 ℃, added 80 parts of potassium sodium tartrate, stirred and melted;

[0082] S3 30 parts of citric acid, 10 parts of malic acid were added to the reactor and stirred for 5min, 0.2 parts of sodium fluoride was added and stirred for 5min;

[0083] S4. The reactor temperature was raised to 70°C, 100 parts of copper sulfate and 20 parts of spherical graphite were added and stirred, and aqueous ammonia was added to the solution to adjust the pH to 8, 10 parts of hydrazine were added and stirred for 1h;

[0084] S5 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate were added to the reactor, the temperature was raised to 75 ° C, and ammonia was added to the solution to adjust the pH to 9, 10 parts of hydrazine was added and stirred for 1h;

[0085] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0086] The graphite is flake graphite.

[0087] The D50 particle size of the spherical graphite is 10 μm.

[0088] The flake graphite was purchased from Shandong Xiangzhao New Materials Co., Ltd., model number XZ.

[0089] The copper sulfate was purchased from Jinan Guocheng Chemical Co., Ltd., and the mass content was 99.9%.

[0090] The potassium sodium tartrate was purchased from Jiangsu Caiwei Biotechnology Co., Ltd., with a mass content of 99%.

[0091] The sodium fluoride was purchased from Shandong Liang New Material Technology Co., Ltd., with a mass content of 99%.

[0092] The thiourea was purchased from Shandong Changyao New Materials Co., Ltd., model number cy-845120.

[0093] The nickel sulfate was purchased from Shandong Liang New Material Technology Co., Ltd., model LA-5V.

[0094] Example 2

[0095] A conductive powder comprises the following raw materials, measured by weight: 20 parts of graphite, 80 parts of copper sulfate, 80 parts of potassium sodium tartrate, 30 parts of citric acid, 10 parts of malic acid, 0.2 parts of sodium fluoride, 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate, and 20 parts of hydrazine.

[0096] A method for preparing conductive powder comprises the following steps:

[0097] S1. High temperature calcination of flake graphite, the calcination temperature is from room temperature to 1500 ℃, constant temperature 2h, then heated to 5000 ℃, constant temperature 2h, cooled to room temperature, and after cooling, spherical graphite is obtained by graphite ball press machine;

[0098] S2. The reactor was added with 1000g of water, heated to 65 ℃, added 80 parts of potassium sodium tartrate, stirred and melted;

[0099] S3 30 parts of citric acid, 10 parts of malic acid were added to the reactor and stirred for 5min, 0.2 parts of sodium fluoride was added and stirred for 5min;

[0100] S4. The reactor temperature was raised to 70 ° C, 80 parts of copper sulfate and 20 parts of spherical graphite were added and stirred, and aqueous ammonia was added to the solution to adjust the pH to 8, 10 parts of hydrazine were added and stirred for 1h;

[0101] S5 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate were added to the reactor, the temperature was raised to 75 ° C, and ammonia was added to the solution to adjust the pH to 9, 10 parts of hydrazine was added and stirred for 1h;

[0102] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0103] The graphite is flake graphite.

[0104] The D50 particle size of the spherical graphite is 10 μm.

[0105] The flake graphite was purchased from Shandong Xiangzhao New Materials Co., Ltd., model number XZ.

[0106] The copper sulfate was purchased from Jinan Guocheng Chemical Co., Ltd., and the mass content was 99.9%.

[0107] The potassium sodium tartrate was purchased from Jiangsu Caiwei Biotechnology Co., Ltd., with a mass content of 99%.

[0108] The sodium fluoride was purchased from Shandong Liang New Material Technology Co., Ltd., with a mass content of 99%.

[0109] The thiourea was purchased from Shandong Changyao New Materials Co., Ltd., model number cy-845120.

[0110] The nickel sulfate was purchased from Shandong Liang New Material Technology Co., Ltd., model LA-5V.

[0111] Example 3

[0112] A conductive powder comprises the following raw materials, measured by weight: 20 parts of graphite, 120 parts of copper sulfate, 80 parts of potassium sodium tartrate, 30 parts of citric acid, 10 parts of malic acid, 0.2 parts of sodium fluoride, 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate, and 20 parts of hydrazine.

[0113] A method for preparing conductive powder comprises the following steps:

[0114] S1. High temperature calcination of flake graphite, the calcination temperature is from room temperature to 1500 ℃, constant temperature 2h, then heated to 5000 ℃, constant temperature 2h, cooled to room temperature, and after cooling, spherical graphite is obtained by graphite ball press machine;

[0115] S2. The reactor was added with 1000g of water, heated to 65 ℃, added 80 parts of potassium sodium tartrate, stirred and melted;

[0116] S3 30 parts of citric acid, 10 parts of malic acid were added to the reactor and stirred for 5min, 0.2 parts of sodium fluoride was added and stirred for 5min;

[0117] S4. The reactor temperature was raised to 70 ° C, 120 parts of copper sulfate and 20 parts of spherical graphite were added and stirred, and aqueous ammonia was added to the solution to adjust the pH to 8, 10 parts of hydrazine were added and stirred for 1h;

[0118] S5 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate were added to the reactor, the temperature was raised to 75 ° C, and ammonia was added to the solution to adjust the pH to 9, 10 parts of hydrazine was added and stirred for 1h;

[0119] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0120] The graphite is flake graphite.

[0121] The D50 particle size of the spherical graphite is 10 μm.

[0122] The flake graphite was purchased from Shandong Xiangzhao New Materials Co., Ltd., model number XZ.

[0123] The copper sulfate was purchased from Jinan Guocheng Chemical Co., Ltd., and the mass content was 99.9%.

[0124] The potassium sodium tartrate was purchased from Jiangsu Caiwei Biotechnology Co., Ltd., with a mass content of 99%.

[0125] The sodium fluoride was purchased from Shandong Liang New Material Technology Co., Ltd., with a mass content of 99%.

[0126] The thiourea was purchased from Shandong Changyao New Materials Co., Ltd., model number cy-845120.

[0127] The nickel sulfate was purchased from Shandong Liang New Material Technology Co., Ltd., model LA-5V.

[0128] Example 4

[0129] A conductive powder comprises the following raw materials, measured in parts by weight: 20 parts of graphite, 100 parts of copper sulfate, 80 parts of disodium ethylenediaminetetraacetic acid, 30 parts of citric acid, 10 parts of malic acid, 0.2 parts of sodium fluoride, 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate, and 20 parts of hydrazine.

[0130] A method for preparing conductive powder comprises the following steps:

[0131] S1. High temperature calcination of flake graphite, the calcination temperature is from room temperature to 1500 ℃, constant temperature 2h, then heated to 5000 ℃, constant temperature 2h, cooled to room temperature, and after cooling, spherical graphite is obtained by graphite ball press machine;

[0132] S2. 1000g of water was added to the reactor, the temperature was raised to 65 ° C, 80 parts of disodium edetate was added, and stirred to melt;

[0133] S3 30 parts of citric acid, 10 parts of malic acid were added to the reactor and stirred for 5min, 0.2 parts of sodium fluoride was added and stirred for 5min;

[0134] S4. The reactor temperature was raised to 70°C, 100 parts of copper sulfate and 20 parts of spherical graphite were added and stirred, and aqueous ammonia was added to the solution to adjust the pH to 8, 10 parts of hydrazine were added and stirred for 1h;

[0135] S5 5 parts of thiourea, 100 ml of diethyl phthalate, 150 parts of nickel sulfate were added to the reactor, the temperature was raised to 75 ° C, and ammonia was added to the solution to adjust the pH to 9, 10 parts of hydrazine was added and stirred for 1h;

[0136] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0137] The graphite is flake graphite.

[0138] The D50 particle size of the spherical graphite is 10 μm.

[0139] The flake graphite was purchased from Shandong Xiangzhao New Materials Co., Ltd., model number XZ.

[0140] The copper sulfate was purchased from Jinan Guocheng Chemical Co., Ltd., and the mass content was 99.9%.

[0141] The potassium sodium tartrate was purchased from Jiangsu Caiwei Biotechnology Co., Ltd., with a mass content of 99%.

[0142] The sodium fluoride was purchased from Shandong Liang New Material Technology Co., Ltd., with a mass content of 99%.

[0143] The thiourea was purchased from Shandong Changyao New Materials Co., Ltd., model number cy-845120.

[0144] The nickel sulfate was purchased from Shandong Liang New Material Technology Co., Ltd., model LA-5V.

[0145] Example 5

[0146] A conductive powder comprises the following raw materials, measured by weight: 20 parts of graphite, 100 parts of copper sulfate, 80 parts of potassium sodium tartrate, 30 parts of citric acid, 10 parts of malic acid, 0.2 parts of sodium fluoride, 5 parts of sodium sulfite, 100 ml of diethyl phthalate, 150 parts of nickel sulfate, and 20 parts of hydrazine.

[0147] A method for preparing conductive powder comprises the following steps:

[0148] S1. High temperature calcination of flake graphite, the calcination temperature is from room temperature to 1500 ℃, constant temperature 2h, then heated to 5000 ℃, constant temperature 2h, cooled to room temperature, and after cooling, spherical graphite is obtained by graphite ball press machine;

[0149] S2. The reactor was added with 1000g of water, heated to 65 ℃, added 80 parts of potassium sodium tartrate, stirred and melted;

[0150] S3 30 parts of citric acid, 10 parts of malic acid were added to the reactor and stirred for 5min, 0.2 parts of sodium fluoride was added and stirred for 5min;

[0151] S4. The reactor temperature was raised to 70°C, 100 parts of copper sulfate and 20 parts of spherical graphite were added and stirred, and aqueous ammonia was added to the solution to adjust the pH to 8, 10 parts of hydrazine were added and stirred for 1h;

[0152] S5 5 parts of sodium sulfite, 100 ml of diethyl phthalate, 150 parts of nickel sulfate were added to the reactor, the temperature was raised to 75 ° C, and ammonia was added to the solution to adjust the pH to 9, 10 parts of hydrazine was added and stirred for 1h;

[0153] S6. Filter, wash, dry, and sieve the solution to obtain conductive powder.

[0154] The graphite is flake graphite.

[0155] The D50 particle size of the spherical graphite is 10 μm.

[0156] The flake graphite was purchased from Shandong Xiangzhao New Materials Co., Ltd., model number XZ.

[0157] The copper sulfate was purchased from Jinan Guocheng Chemical Co., Ltd., and the mass content was 99.9%.

[0158] The potassium sodium tartrate was purchased from Jiangsu Caiwei Biotechnology Co., Ltd., with a mass content of 99%.

[0159] The sodium fluoride was purchased from Shandong Liang New Material Technology Co., Ltd., with a mass content of 99%.

[0160] The nickel sulfate was purchased from Shandong Liang New Material Technology Co., Ltd., model LA-5V.

[0161] Performance Testing

[0162] The sample preparation method comprises the following steps:

[0163] S1. Prepare 5 100g portions of acrylic glue;

[0164] S2 Example 1-5 prepared conductive powder diameter of 35um 2g and acrylic glue stirred;

[0165] S3. Apply the stirred glue evenly on the release paper;

[0166] S4. Place in a 110°C oven and remove after 3 minutes.

[0167] S5. Paste the dried glue on the aluminum foil and press it three times with a 2kg roller;

[0168] S6. Remove the release paper and measure the adhesive thickness to be 35 μm.

[0169] S7. Glued aluminum foil was attached to two 40 mm × 40 mm copper blocks, with a spacing of 40 mm. The test specimens were obtained. The test results are shown in Table 1.

[0170] 1. Measure the resistance value

[0171] Test method: The test samples prepared in Examples 1-5 were used to measure the resistance values using a resistance tester.

[0172] 2. Measure electromagnetic shielding value

[0173] Test method: The test samples prepared in Examples 1-5 were used to measure the electromagnetic shielding value using an electromagnetic shielding effectiveness tester.

[0174] Table 1

[0175] Example Resistance value mΩ Electromagnetic shielding value db Example 1 8 100 Example 2 9 98 Example 3 10 99 Example 4 300 45 Example 5 35 65

[0176] The foregoing examples are merely illustrative and serve to explain some features of the method of the present invention. The appended claims are intended to claim the widest possible range that can be envisioned, and the embodiments presented herein are merely illustrations of selected implementations according to a combination of all possible embodiments. Therefore, it is the applicant's intention that the appended claims are not limited by the selection of examples illustrating the features of the present invention. Some numerical ranges used in the claims also include subranges therein, and variations in these ranges should also be interpreted as being covered by the appended claims where possible.

Claims

1. A conductive powder, characterized in that: The raw materials include the following components by weight: 5-50 parts of graphite, 80-120 parts of copper salt, 50-100 parts of complexing agent, 20-80 parts of acidic compound, 100-200 parts of nickel salt, and 10-30 parts of reducing agent; the conductive powder also includes a complexing agent; The graphite is flake graphite; The weight ratio of the complexing agent to the copper salt is 1:(0.8-1.5); The complexing agent is potassium sodium tartrate; The complexing agent is thiourea.

2. The conductive powder according to claim 1, wherein The acidic compound is a hydroxy acid or an amino acid.

3. The conductive powder according to claim 1, wherein The raw materials also include inorganic salts and plasticizers; The inorganic salt is selected from one or more of calcium salt, potassium salt, sodium salt, chloride salt and magnesium salt; The plasticizer is selected from phthalate compounds, phosphate compounds, and fatty acid compounds.

4. The method for preparing the conductive powder according to any one of claims 1 to 3, comprising the following steps: S1, calcining graphite, and obtaining spherical graphite using a graphite ball press after cooling; S2, adding water and complexing agent into the reactor; S3, adding an acidic compound to a reaction kettle and stirring, adding an inorganic salt and stirring; S4, adding copper salt and spherical graphite into a reactor and stirring, and then adding a reducing agent and stirring; S5, adding a complexing agent, a plasticizer, and a nickel salt into a reaction kettle, and then adding a reducing agent and stirring; S6. Filter, wash, dry and sieve the solution to obtain conductive powder.

5. The method for preparing the conductive powder according to claim 4, wherein: The D50 particle size of the spherical graphite in S1 is 0.5-50 μm.

6. The method for preparing the conductive powder according to claim 5, wherein: The D50 particle size of the spherical graphite in S1 is 2-30 μm.