Disclosure of Invention
Therefore, the technical problem to be solved by the invention is that the lithium ion battery using lithium iodide as the anode material is adopted, so that the composite carbon material and the application thereof in the lithium ion battery are provided.
In order to solve the technical problems, the technical scheme adopted by the invention is as follows:
the invention provides a preparation method of a composite carbon material, which comprises the following steps:
s1: dispersing carbon nano tubes, a surfactant and glucose in deionized water, and then carrying out hydrothermal reaction to obtain hydrothermal carbon;
s2: drying and carbonizing the hydrothermal carbon, mixing the carbonized hydrothermal carbon with potassium hydroxide, and performing an activation reaction to obtain a rough composite carbon material;
s3: and washing the crude composite carbon material to be neutral, and drying to obtain the composite carbon material.
Furthermore, the diameter of the carbon nano tube is 5-20nm, and the length of the carbon nano tube is 5-15 μm;
the surfactant is Sodium Dodecyl Benzene Sulfonate (SDBS).
The mass ratio of the carbon nano tube to the surfactant to the glucose is 5-12:1: 800-1500.
In the step S1, the hydrothermal reaction temperature is 160-200 ℃, and the reaction time is 7-12 h;
in step S2, carbonization is carried out for reaction for 1-3h at 900 ℃ under the argon environment;
the activation reaction is 800-1000 ℃ for 1-3 h.
The invention also provides a composite carbon material prepared by the preparation method.
The invention also provides a lithium ion battery anode slurry which comprises the following raw materials in parts by mass:
80-90 parts of lithium iodide;
6-10 parts of conductive carbon;
4-10 parts of a binder;
the conductive carbon is a mixture of the composite carbon material and at least one of Ketjen Black (KB), carbon black (Super-P), multi-walled carbon nanotubes (MWCNT) or graphene (RGO), and the composite carbon material accounts for 20-80 wt% of the conductive carbon;
the binder is at least one of polyvinyl butyral (PVB), polyvinylpyrrolidone (PVP), vinylpyrrolidone-vinyl acetate copolymer (PVP-VA) or polyethylene glycol (PEG 2000).
The preparation method of the lithium ion battery anode slurry comprises the steps of fully dispersing lithium iodide in ethanol, and then mixing conductive carbon and a binder to obtain the lithium ion battery anode slurry, wherein the water content in the ethanol is less than 200 ppm.
The preparation method of the lithium ion battery positive pole piece comprises the steps of coating the lithium ion battery positive pole slurry on a current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The invention also provides a lithium ion battery, which takes the lithium ion battery anode piece as an anode piece.
The preparation method of the lithium ion battery comprises the steps of packaging a dry electric core obtained by assembling the positive pole piece, the negative pole piece and the electrolyte, drying, injecting liquid, standing and forming to obtain the lithium ion battery.
The cathode pole piece can select a graphite cathode, a silicon-carbon cathode or lithium metal as a cathode, and the electrolyte is DOL/DME (1:1 vol.%) of 1M LiTFSI.
The scheme provided by the invention has the following advantages:
1. in the preparation process of the carbon composite material, hydrothermal carbon obtained by glucose through hydrothermal reaction is further carbonized to obtain carbon-coated carbon nano tubes, and the carbon-coated carbon nano tubes are activated by potassium hydroxide to obtain the carbon composite material with the specific surface area of 2500-4000m2A carbon composite material per gram.
2. When the carbon composite material provided by the invention is applied to a lithium ion battery taking LiI as a positive electrode material, the LiI in the electrode material can be adsorbed by the ultrahigh specific surface area of the carbon composite material, the shuttle effect of the LiI in the battery is inhibited, and the self-discharge of the lithium ion battery is reduced; the carbon nano tube in the composite material can improve the rate characteristic and the cycle stability of the lithium ion battery while improving the conductivity and the mechanical stability of the material.
3. According to the invention, multiple carbon materials are selected and combined, and carbon materials with different properties are compounded in multiple ways, so that the contact among electrode active materials is greatly increased, the conductivity is improved, and the lithium ion battery is convenient to charge and discharge quickly.
4. The material used in the invention is easy to obtain, the preparation method is simple, and the industrial production is convenient.
Detailed Description
The following examples are provided to better understand the present invention, not to limit the best mode, and not to limit the content and protection scope of the present invention, and any product that is the same or similar to the present invention and is obtained by combining the present invention with other features of the prior art and the present invention falls within the protection scope of the present invention.
The examples do not show the specific experimental steps or conditions, and can be performed according to the conventional experimental steps described in the literature in the field. The reagents or instruments used are not indicated by manufacturers, and are all conventional reagent products which can be obtained commercially.
Example 1
The embodiment provides a composite carbon material, and a preparation method thereof comprises the following steps:
(1) weighing 0.1g of carbon nano tube, 10mg of sodium dodecyl benzene sulfonate and 10g of glucose, adding into 100ml of deionized water, and performing ultrasonic dispersion uniformly;
(2) pouring the uniformly dispersed carbon nanotube aqueous solution into a hydrothermal reaction kettle, and carrying out hydrothermal reaction at 190 ℃ for 10 hours to obtain hydrothermal carbon;
(3) drying hydrothermal carbon reacted in a hydrothermal kettle, transferring the hydrothermal carbon into a tubular furnace, introducing argon for protection, and carbonizing at 800 ℃ for 2 hours to obtain carbon-coated carbon nanotubes; uniformly mixing the carbon-coated carbon nano tube with potassium hydroxide according to the mass ratio of 1:5, transferring the mixture into a tubular furnace, and performing activation reaction at 800 ℃ for 1 hour to obtain a crude composite carbon material;
(4) and washing the crude composite carbon material to be neutral, and drying to obtain the composite carbon material.
The embodiment also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 80g of lithium iodide into a ball milling tank, carrying out ball milling for 20min, then adding 6g of Ketjen black, 2g of multi-walled carbon nanotubes, 2g of composite carbon material and 10g of polyvinylpyrrolidone powder, and continuing to carry out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 38 wt.%.
The embodiment also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
transferring the slurry to an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The embodiment also provides a lithium ion battery, and the preparation method comprises the following steps:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) stacking the positive pole piece, the isolating membrane and the negative pole piece in sequence, wrapping the battery cell by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished lithium ion battery.
Example 2
The embodiment provides a composite carbon material, and the preparation method comprises the following steps:
(1) 0.1g of carbon nano tube, 10mg of sodium dodecyl benzene sulfonate and 10g of glucose are weighed and added into 100ml of deionized water, and the mixture is uniformly dispersed by ultrasonic;
(2) pouring the uniformly dispersed carbon nanotube aqueous solution into a hydrothermal reaction kettle, and carrying out hydrothermal reaction at 190 ℃ for 10 hours to obtain hydrothermal carbon;
(3) drying the hydrothermal carbon reacted in the hydrothermal kettle, transferring the hydrothermal carbon into a tube furnace, introducing argon for protection, and carbonizing at 800 ℃ for 2 hours to obtain carbon-coated carbon nanotubes; uniformly mixing the carbon-coated carbon nano tube with potassium hydroxide according to the mass ratio of 1:5, transferring the mixture into a tubular furnace, and performing activation reaction at 800 ℃ for 1 hour to obtain a crude composite carbon material;
(4) and washing the crude composite carbon material with water to be neutral, and drying to obtain the composite carbon material.
The embodiment also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 80g of lithium iodide into a ball milling tank, adding ethanol, carrying out ball milling for 20min, then adding 4g of Ketjen black, 2g of multi-walled carbon nanotubes, 4g of composite carbon material and 10g of polyvinylpyrrolidone powder, and continuing to carry out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 38 wt.%.
The embodiment also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
transferring the slurry to an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The embodiment also provides a lithium ion battery, and the preparation method comprises the following steps:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) sequentially stacking the positive pole piece, the isolating membrane and the negative pole piece, wrapping the battery core by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished product of the lithium ion battery.
Example 3
The embodiment provides a composite carbon material, and the preparation method comprises the following steps:
(1) weighing 0.1g of carbon nano tube, 10mg of sodium dodecyl benzene sulfonate and 10g of glucose, adding into 100ml of deionized water, and performing ultrasonic dispersion uniformly;
(2) pouring the uniformly dispersed carbon nanotube aqueous solution into a hydrothermal reaction kettle, and carrying out hydrothermal reaction at 190 ℃ for 10 hours to obtain hydrothermal carbon;
(3) drying hydrothermal carbon reacted in a hydrothermal kettle, transferring the hydrothermal carbon into a tubular furnace, introducing argon for protection, and carbonizing at 800 ℃ for 2 hours to obtain carbon-coated carbon nanotubes; uniformly mixing the carbon-coated carbon nano tube with potassium hydroxide according to the mass ratio of 1:5, transferring the mixture into a tubular furnace, and performing activation reaction at 800 ℃ for 1 hour to obtain a crude composite carbon material;
(4) and washing the crude composite carbon material with water to be neutral, and drying to obtain the composite carbon material.
The embodiment also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 90g of lithium iodide into a ball milling tank, adding ethanol, carrying out ball milling for 20min, then adding 2g of Ketjen black, 2g of multi-walled carbon nanotube, 2g of composite carbon material, 3g of vinylpyrrolidone-vinyl acetate copolymer powder and 1g of polyethylene glycol powder, and continuing carrying out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 33 wt.%.
The embodiment also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
transferring the slurry to an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The present embodiment also provides a lithium ion battery, and the preparation method includes:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) sequentially stacking the positive pole piece, the isolating membrane and the negative pole piece, wrapping the battery core by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished product of the lithium ion battery.
Example 4
The embodiment provides a composite carbon material, and the preparation method comprises the following steps:
(1) 0.1g of carbon nano tube, 10mg of sodium dodecyl benzene sulfonate and 10g of glucose are weighed and added into 100ml of deionized water, and the mixture is uniformly dispersed by ultrasonic;
(2) pouring the uniformly dispersed carbon nanotube aqueous solution into a hydrothermal reaction kettle, and carrying out hydrothermal reaction at 190 ℃ for 10 hours to obtain hydrothermal carbon;
(3) drying hydrothermal carbon reacted in a hydrothermal kettle, transferring the hydrothermal carbon into a tubular furnace, introducing argon for protection, and carbonizing at 800 ℃ for 2 hours to obtain carbon-coated carbon nanotubes; uniformly mixing the carbon-coated carbon nano tube with potassium hydroxide according to the mass ratio of 1:5, transferring the mixture into a tubular furnace, and performing activation reaction at 800 ℃ for 1 hour to obtain a crude composite carbon material;
(4) and washing the crude composite carbon material to be neutral, and drying to obtain the composite carbon material.
The embodiment also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 90g of lithium iodide into a ball milling tank, adding ethanol, carrying out ball milling for 20min, then adding 2g of Ketjen black, 1g of multi-walled carbon nanotube, 1g of graphene, 2g of composite carbon material, 3g of polyvinyl butyral powder and 1g of vinyl pyrrolidone-vinyl acetate copolymer powder, and continuing carrying out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 32 wt.%.
The embodiment also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
transferring the slurry to an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The present embodiment also provides a lithium ion battery, and the preparation method includes:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) sequentially stacking the positive pole piece, the isolating membrane and the negative pole piece, wrapping the battery core by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished product of the lithium ion battery.
Example 5
The embodiment provides a composite carbon material, and a preparation method thereof comprises the following steps:
(1) 0.1g of carbon nano tube, 10mg of sodium dodecyl benzene sulfonate and 10g of glucose are weighed and added into 100ml of deionized water, and the mixture is uniformly dispersed by ultrasonic;
(2) pouring the uniformly dispersed carbon nanotube aqueous solution into a hydrothermal reaction kettle, and carrying out hydrothermal reaction at 190 ℃ for 10 hours to obtain hydrothermal carbon;
(3) drying the hydrothermal carbon reacted in the hydrothermal kettle, transferring the hydrothermal carbon into a tube furnace, introducing argon for protection, and carbonizing at 800 ℃ for 2 hours to obtain carbon-coated carbon nanotubes; uniformly mixing carbon-coated carbon nanotubes and potassium hydroxide according to the mass ratio of 1:5, transferring the mixture into a tubular furnace, and carrying out activation reaction at 800 ℃ for 1h to obtain a crude composite carbon material;
(4) and washing the crude composite carbon material with water to be neutral, and drying to obtain the composite carbon material.
The embodiment also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 90g of lithium iodide into a ball milling tank, adding ethanol, carrying out ball milling for 20min, then adding 1g of multi-walled carbon nanotubes, 1g of graphene, 4g of activated carbon coated carbon nanotube material, 3g of polyvinyl butyral powder and 1g of polyvinylpyrrolidone powder, and continuing to carry out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 30 wt.%.
The embodiment also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
transferring the slurry to an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The present embodiment also provides a lithium ion battery, and the preparation method includes:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) sequentially stacking the positive pole piece, the isolating membrane and the negative pole piece, wrapping the battery core by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished product of the lithium ion battery.
Comparative example 1
The comparative example also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 80g of lithium iodide into a ball milling tank, adding ethanol, carrying out ball milling for 20min, then adding 10g of multi-walled carbon nanotubes and 10g of polyvinylpyrrolidone powder, and continuing carrying out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 38 wt.%.
The comparative example also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
transferring the slurry to an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The comparative example also provides a lithium ion battery, and the preparation method comprises the following steps:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) stacking the positive pole piece, the isolating membrane and the negative pole piece in sequence, wrapping the battery cell by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished lithium ion battery.
Comparative example 2
The comparative example also provides a lithium ion battery anode slurry, and the preparation method comprises the following steps:
adding 90g of lithium iodide into a ball milling tank, adding ethanol, carrying out ball milling for 20min, then adding 6g of multi-walled carbon nanotubes and 4g of polyvinylpyrrolidone powder, and continuing carrying out ball milling for 4h to obtain uniformly dispersed anode slurry with the solid content of 38 wt.%.
The comparative example also provides a lithium ion battery positive pole piece, and the preparation method comprises the following steps:
and transferring the slurry into an inert environment glove box, coating the slurry on a stainless steel current collector in an inert environment, and drying to obtain the lithium ion battery positive pole piece.
The comparative example also provides a lithium ion battery, and the preparation method comprises the following steps:
mixing a negative active material graphite, conductive carbon black, a binder SBR, a thickening agent CMC and cyclic ester ethylene carbonate according to a mass ratio of 93.5:2:3:0.5:1, adding a deionized water solvent, fully and uniformly stirring to obtain a negative slurry, coating the negative slurry on a stainless steel current collector, and drying to obtain the lithium ion battery negative pole piece. And (3) sequentially stacking the positive pole piece, the isolating membrane and the negative pole piece, wrapping the battery core by using an aluminum plastic membrane, injecting DOL/DME (1:1 vol.%) electrolyte containing 1M LiTFSI, and then packaging to obtain the finished product of the lithium ion battery.
Test examples
The lithium ion batteries obtained in the examples and comparative examples were subjected to performance tests.
The test items include the charge and discharge tests of 0.3C, 1C, 5C and 10℃ at the normal temperature of 25 ℃ and the tests of 1C at the temperature of 0 ℃, 10 ℃, 20 ℃ and 30 ℃, and the test results are shown in tables 1 and 2.
TABLE 1 volume retention at different temperatures for each of the examples and comparative examples
TABLE 2 volume retention test for various turns of each example and comparative example
As can be seen from the above 2 tables, the lithium ion battery of the comparative example without the composite carbon material provided in the present application has far inferior low temperature performance and long cycle performance to the examples of the present application, which shows that the composite carbon material provided in the present application can improve the capacity retention rate of the lithium ion battery at low temperature and the capacity retention rate in the long cycle life test.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications therefrom are within the scope of the invention.