Background
The lithium battery is used as a novel chemical power supply developed in the nineties of the twentieth century, has the outstanding advantages of high working voltage, light weight, high specific capacity, small self-discharge, long cycle life, no memory effect, safety, reliability, environmental protection and the like, becomes an important field for supporting the electronic industry technology, becomes an ideal energy source for small and light electronic devices such as mobile phones, notebook computers, digital cameras and the like, and is also a preferred power supply for light high-power batteries such as power automobiles, electric tools and the like in the future.
The lithium battery generally consists of three parts, namely a positive electrode, a negative electrode and an electrolyte, and a battery chemical system determines the electrochemical reaction of the battery, so that the theoretical voltage, the theoretical specific capacity and the theoretical specific energy of the battery are determined. The positive electrode material occupies a large proportion, the performance of the positive electrode material directly influences the performance of the lithium ion battery, the cost of the positive electrode material directly determines the cost of the battery, and the research on the positive electrode material is an important aspect for improving the electrochemical performance of the battery.
LiMPO having an olivine-type structure in a lithium battery positive electrode material4(M = Fe, Mn, Co, Ni) attracts a lot of attention in recent years, and has the characteristics of higher theoretical specific capacity, better cycle performance, stability, safety, environmental friendliness, low price and the like. Among them, nickel has an advantage of higher energy density, and thus, research on a lithium nickel phosphate positive electrode material is increasing.
The Chinese patent application No. 201310279311.1 discloses an in-situ carbon coating preparation method of a lithium nickel phosphate as a cathode material of a secondary lithium ion battery. (1) Dissolving a lithium source compound, a divalent nickel source compound, phosphate and a carbon source in a benzyl alcohol aqueous solution; (2) carrying out hydrothermal reaction for 4-10 h at 100-200 ℃; (3) performing suction filtration, and cleaning with distilled water and absolute ethyl alcohol; (4) drying at 50-100 ℃; (5) and fully grinding the dried powder, pretreating, and calcining at high temperature to obtain the final product. The conductivity of the lithium nickel phosphate cathode material prepared by the method is still not ideal enough, and the high-rate cycle performance needs to be improved.
The Chinese patent application No. 201310402157.2 discloses a method for microwave solid phase synthesis of a lithium nickel phosphate/carbon composite material for a lithium ion battery, which has the advantages of potential high energy density, low synthesis cost, environmental friendliness and the like. The invention selects synthetic raw materials comprising lithium salt (or lithium hydroxide), phosphate, ammonium phosphate salt, nickel salt and conductive carbon black (or acetylene black or glucose). Firstly, after ball milling or stirring treatment is carried out on raw materials, when the microwave power is 300-2000W, the synthesis time is 5-30 min, and the nickel lithium phosphate/carbon composite material for the lithium ion battery can be synthesized in one step. However, when the composite material prepared by the invention is used for a lithium battery, the defects of unsatisfactory charge-discharge specific capacity and cycle performance under high rate exist.
In conclusion, the lithium nickel phosphate cathode material has the defects of poor ionic conductivity and serious reduction of specific capacity and cycle performance under high rate, so the development of the lithium nickel phosphate cathode material with high conductivity and good cycle stability under high rate has important significance.
Disclosure of Invention
Therefore, the lithium nickel phosphate anode material has the defects of poor ionic conductivity, and serious reduction of specific capacity and cycle performance under high rate. Aiming at the situation, the invention provides a copper-magnesium doped coated nickel lithium phosphate positive electrode material for a lithium battery and a preparation method thereof.
In order to achieve the purpose, the invention relates to the following specific technical scheme:
the preparation method of the copper-magnesium doped coated lithium nickel phosphate anode material for the lithium battery comprises the following specific steps of:
(1) preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 120-125 ℃ in a sealed state, reacting for 4-5 h, then introducing nitrogen, heating to 170-180 ℃, continuing to react for 1-2 h, then cooling, discharging, filtering, washing and drying in vacuum to obtain the copper-magnesium doped nickel lithium phosphate material;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, performing wet ball milling for 8-10 hours, and discharging to obtain a coating liquid precursor;
(3) depositing the coating liquid precursor prepared in the step (2) on the surface of the copper-magnesium doped nickel lithium phosphate material prepared in the step (1) through spray drying, then placing the material in a muffle furnace, pre-burning the material at 550-650 ℃ for 7-8 h, heating the material to 700-750 ℃ for sintering for 2-3 h, completely carbonizing the carboxymethyl cellulose, and generating lithium carbonate and vanadium pentoxideLi3VO4To obtain Li3VO4the/C mixed coated copper-magnesium doped lithium nickel phosphate cathode material.
Preferably, in the mixed solution in the step (1), the molar ratio of the hexadecyl trimethyl ammonium bromide to the ethanol to the deionized water is 1-3: 30-70.
Because the electrochemical performance of the anode material is related to the particle size of the nickel lithium phosphate particles, the smaller the particle size is, the more uniform the particle size distribution is, the larger the corresponding specific surface area is, the shorter the path for lithium ions to diffuse to the particle surface is, the higher the ion diffusion rate is, and thus the electrochemical performance of the anode material is improved, therefore, the hexadecyl trimethyl ammonium bromide is adopted as the surfactant, the purpose of controlling the growth of the nickel lithium phosphate crystal grains can be achieved, and the particle size of the prepared nickel lithium phosphate particles is 0.5-1 mu m.
The chemical formula of the synthesized doped lithium nickel phosphate is LiNi1-x-yMgxCuyPO4Therefore, the molar ratio of the required raw materials of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1:1 (1-x-y): x: y, but Li is volatile during high-temperature treatment, and the molar ratio of lithium hydroxide is 10-20% when the raw material proportion is selected, so that the preferable scheme of the invention is that the molar ratio of the lithium hydroxide, the ammonium dihydrogen phosphate, the nickel sulfate, the magnesium sulfate and the copper sulfate in the step (1) is 1.1-1.2: 1 (1-x-y): x: y, wherein x can be one of 0.05, 0.1, 0.15 and 0.2, and y can be one of 0.05, 0.1, 0.15 and 0.2.
By adopting metal ion doping, the electrochemical performance of the nickel lithium phosphate can be improved, and the high-rate stability and the cycle performance of the nickel lithium phosphate can be improved. The doped magnesium ions and copper ions replace part of nickel ions, but the crystal structure of the nickel lithium phosphate is not changed, the electrochemical dynamics capability of the nickel lithium phosphate is enhanced by enhancing the internal contraction of crystal lattices, the reversible capacity is improved, and the good cycle performance is realized. Since the particle size of the lithium nickel phosphate tends to decrease and then increase with the increase of the molar ratio of the dopant ions, it is preferable that the value of x is not more than 0.2 and the value of y is not more than 0.2 in order to ensure that the particles of the copper-magnesium doped lithium nickel phosphate obtained are small and uniform.
Preferably, the temperature of the vacuum drying in the step (1) is 40-60 ℃, and the time is 8-10 h.
Preferably, in the preparation of the coating liquid precursor in the step (2), the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 3-5: 10-20: 3: 1.
Preferably, the heating temperature in the step (2) is 50-70 ℃.
According to the invention, carboxymethyl cellulose is used as a carbon source, a carbon layer is formed on the surface of copper-magnesium doped nickel lithium phosphate particles through high-temperature sintering, the formation of a conductive network is promoted, and further, Li is generated in situ by taking lithium carbonate and vanadium pentoxide as raw materials3VO4Form a mixed coating with a carbon layer, Li on the one hand3VO4Can repair incomplete carbon coating layer, on the other hand due to Li3VO4The lithium ion battery has a 3D pore structure, can provide more channels for the diffusion of lithium ions, obviously improves the diffusion rate of the lithium ions, and improves the high-rate performance of doped lithium nickel phosphate. By Li3VO4The mixed coating of/C can also prevent the electrolyte from dissolving the anode material.
Preferably, the spraying rotation speed of the spray drying in the step (3) is 15000-18000 r/min, and the diameter of the spraying disc is 120-150 mm.
Preferably, the weight ratio of the coating liquid precursor in the step (3) to the copper-magnesium doped nickel lithium phosphate material is 1-2: 10.
The invention also provides the copper-magnesium doped coated nickel lithium phosphate anode material for the lithium battery, which is prepared by the preparation method. The lithium nickel phosphate cathode material is prepared from Li3VO4the/C mixed coating is doped by copper and magnesium metal ions, and the copper and magnesium doped nickel lithium phosphate material LiNi is prepared by a hydrothermal method in the presence of a surfactant1-x-yMgxCuyPO4Then, a coating liquid precursor containing carboxymethyl cellulose, lithium carbonate and vanadium pentoxide is sprayed and deposited on the LiNi1-x-yMgxCuyPO4Surface of the particles, warpPre-sintering at 550-650 ℃ and sintering at 700-750 ℃. The prepared positive electrode material has the ionic conductivity of 2.2-2.5 multiplied by 10-2S/cm, the first charge-discharge specific capacity of the assembled button cell is 150-160 mAh/g at 0.1C, and the capacity retention rate is 94-96% after 50 weeks of charge-discharge circulation; the 1C multiplying power is 135-145 mAh/g, and the capacity retention rate is 90-93% after 50 weeks of charge-discharge circulation; the 5C multiplying power is 115-125 mAh/g, and the capacity retention rate after 50 weeks of charge-discharge circulation is 84-87%; the 10C multiplying power is 90-100 mAh/g, and the capacity retention rate after 50 weeks of charge-discharge circulation is 75-78%.
The invention provides a copper-magnesium doped coated lithium nickel phosphate anode material for a lithium battery and a preparation method thereof, and compared with the prior art, the copper-magnesium doped coated lithium nickel phosphate anode material has the outstanding characteristics and excellent effects that:
1. according to the preparation method disclosed by the invention, the grain growth is controlled, so that the prepared lithium nickel phosphate anode material is fine in particle size and uniform in particle size distribution, the lithium ion diffusion path is short, the diffusion rate is high, the electrochemical performance of lithium nickel phosphate is improved, and the ionic conductivity is improved.
2. According to the preparation method, the nickel lithium phosphate is doped by the magnesium ions and the copper ions, so that the electrochemical performance, the specific capacity under high rate and the cycle performance of the nickel lithium phosphate are improved.
3. The preparation method of the invention is carried out by Li3VO4the/C is used for mixing and coating the doped lithium nickel phosphate, so that a complete carbon coating layer conductive network can be formed, more channels are provided for the diffusion of lithium ions, the diffusion rate of the lithium ions is improved, the high-rate performance of the doped lithium nickel phosphate is improved, and the dissolution of electrolyte to an anode material can be prevented.
Detailed Description
The present invention will be described in further detail with reference to specific embodiments, but it should not be construed that the scope of the present invention is limited to the following examples. Various substitutions and alterations can be made by those skilled in the art and by conventional means without departing from the spirit of the method of the invention described above.
Example 1
(1) Preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 123 ℃ in a sealed state, reacting for 4.5h, then introducing nitrogen, heating to 176 ℃, continuing to react for 1.5h, then cooling, discharging, carrying out suction filtration, washing and vacuum drying to obtain the copper-magnesium doped nickel lithium phosphate material; in the mixed solution, the mol ratio of cetyl trimethyl ammonium bromide, ethanol and deionized water is 2:50: 55; the molar ratio of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1.14:1:0.8:0.1: 0.1; the temperature of vacuum drying is 48 ℃, and the time is 9 h;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, carrying out wet ball milling for 9 hours, and discharging to obtain a coating liquid precursor; in the preparation of the coating liquid precursor, the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 4:16:3: 1; the heating temperature is 58 ℃;
(3) depositing the coating liquid precursor prepared in the step (2) on the surface of the copper-magnesium doped nickel lithium phosphate material prepared in the step (1) through spray drying, then placing the material in a muffle furnace, presintering the material at 590 ℃ for 7.5h, and then heating the material to 730 ℃ for sintering the material for 2.5h to prepare Li3VO4a/C mixed coated copper-magnesium doped lithium nickel phosphate anode material; the spraying rotating speed of the spray drying is 17000r/min, and the diameter of a spraying disc is 130 mm; the weight ratio of the coating liquid precursor to the copper-magnesium doped lithium nickel phosphate material is 1.4: 10.
Example 2
(1) Preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 121 ℃ in a sealed state, reacting for 5 hours, then introducing nitrogen, heating to 172 ℃, continuing to react for 2 hours, then cooling, discharging, performing suction filtration, washing and vacuum drying to obtain a copper-magnesium doped nickel lithium phosphate material; in the mixed solution, the mol ratio of cetyl trimethyl ammonium bromide, ethanol and deionized water is 1:40: 45; the molar ratio of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1.1:1:0.85:0.05: 0.1; the temperature of vacuum drying is 45 ℃ and the time is 9.5 h;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, performing wet ball milling for 8.5 hours, and discharging to obtain a coating liquid precursor; in the preparation of the coating liquid precursor, the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 3:13:3: 1; the heating temperature is 55 ℃;
(3) depositing the coating liquid precursor prepared in the step (2) on the surface of the copper-magnesium doped nickel lithium phosphate material prepared in the step (1) through spray drying, then placing the material in a muffle furnace, presintering the material at 560 ℃ for 8h, heating the material to 710 ℃ and sintering the material for 3h to prepare Li3VO4a/C mixed coated copper-magnesium doped lithium nickel phosphate anode material; the spraying rotating speed of the spray drying is 16000r/min, and the diameter of the spraying disc is 130 mm; the weight ratio of the coating liquid precursor to the copper-magnesium doped lithium nickel phosphate material is 1.3: 10.
Example 3
(1) Preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 14 ℃ in a sealed state, reacting for 4 hours, then introducing nitrogen, heating to 178 ℃, continuing to react for 1 hour, then cooling, discharging, filtering, washing and drying in vacuum to obtain the copper-magnesium doped nickel lithium phosphate material; in the mixed solution, the mol ratio of cetyl trimethyl ammonium bromide, ethanol and deionized water is 3:60: 65; the molar ratio of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1.2:1:0.65:0.2: 0.15; the temperature of vacuum drying is 55 ℃, and the time is 8.5 h;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, carrying out wet ball milling for 9.5 hours, and discharging to obtain a coating liquid precursor; in the preparation of the coating liquid precursor, the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 4.5:18:3: 1; the heating temperature is 65 ℃;
(3) depositing the coating liquid precursor prepared in the step (2) on the surface of the copper-magnesium doped nickel lithium phosphate material prepared in the step (1) through spray drying, then placing the material in a muffle furnace, presintering the material at 620 ℃ for 7h, and then heating the material to 740 ℃ to sinter the material for 2h to prepare Li3VO4a/C mixed coated copper-magnesium doped lithium nickel phosphate anode material; the spraying rotating speed of the spray drying is 17000r/min, and the diameter of a spraying disc is 140 mm; the weight ratio of the coating liquid precursor to the copper-magnesium doped lithium nickel phosphate material is 1.7: 10.
Example 4
(1) Preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 120 ℃ in a sealed state, reacting for 5 hours, then introducing nitrogen, heating to 170 ℃, continuing to react for 2 hours, then cooling, discharging, performing suction filtration, washing and vacuum drying to obtain a copper-magnesium doped nickel lithium phosphate material; in the mixed solution, the mol ratio of cetyl trimethyl ammonium bromide, ethanol and deionized water is 1:30: 30; the molar ratio of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1.1:1:0.9: 0.05: 0.05; the temperature of vacuum drying is 40 ℃, and the time is 10 hours;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, performing wet ball milling for 8 hours, and discharging to obtain a coating liquid precursor; in the preparation of the coating liquid precursor, the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 3:10:3: 1; the heating temperature is 50 ℃;
(3) depositing the coating liquid precursor prepared in the step (2) on the coating liquid precursor prepared in the step (1) through spray dryingThe surface of the obtained copper-magnesium doped nickel lithium phosphate material is placed in a muffle furnace, presintered for 8 hours at 550 ℃, heated to 700 ℃ and sintered for 3 hours to obtain Li3VO4a/C mixed coated copper-magnesium doped lithium nickel phosphate anode material; the spraying rotating speed of the spray drying is 15000r/min, and the diameter of a spraying disc is 120 mm; the weight ratio of the coating liquid precursor to the copper-magnesium doped lithium nickel phosphate material is 1: 10.
Example 5
(1) Preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 125 ℃ in a sealed state, reacting for 4 hours, then introducing nitrogen, heating to 180 ℃, continuing to react for 1 hour, then cooling, discharging, performing suction filtration, washing and vacuum drying to obtain a copper-magnesium doped nickel lithium phosphate material; in the mixed solution, the mol ratio of cetyl trimethyl ammonium bromide, ethanol and deionized water is 3: 70: 70; the molar ratio of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1.2:1:0.6:0.2: 0.2; the temperature of vacuum drying is 60 ℃, and the time is 8 hours;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, performing wet ball milling for 10 hours, and discharging to obtain a coating liquid precursor; in the preparation of the coating liquid precursor, the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 5: 20:3: 1; the heating temperature is 70 ℃;
(3) depositing the coating liquid precursor prepared in the step (2) on the surface of the copper-magnesium doped nickel lithium phosphate material prepared in the step (1) through spray drying, then placing the material in a muffle furnace, presintering the material at 650 ℃ for 7h, and then heating the material to 750 ℃ to sinter the material for 2h to prepare Li3VO4a/C mixed coated copper-magnesium doped lithium nickel phosphate anode material; the spraying rotating speed of the spray drying is 18000r/min, and the diameter of a spraying disc is 150 mm; the weight ratio of the coating liquid precursor to the copper-magnesium doped lithium nickel phosphate material is 2: 10.
Example 6
(1) Preparing mixed solution of hexadecyl trimethyl ammonium bromide, ethanol and deionized water, adding lithium hydroxide, stirring and dissolving, then adding ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate, stirring uniformly, transferring to a hydrothermal reaction kettle, heating to 122 ℃ in a sealed state, reacting for 4.5h, then introducing nitrogen, heating to 175 ℃, continuing to react for 1.5h, then cooling, discharging, carrying out suction filtration, washing and vacuum drying to obtain the copper-magnesium doped nickel lithium phosphate material; in the mixed solution, the mol ratio of cetyl trimethyl ammonium bromide, ethanol and deionized water is 2:50: 50; the molar ratio of lithium hydroxide, ammonium dihydrogen phosphate, nickel sulfate, magnesium sulfate and copper sulfate is 1.15:1:0.7:0.15: 0.15; the temperature of vacuum drying is 50 ℃, and the time is 9 h;
(2) adding carboxymethyl cellulose into deionized water, heating and stirring until the carboxymethyl cellulose is completely dissolved, then adding lithium carbonate and vanadium pentoxide for dispersion, transferring the mixture into a ball milling tank, carrying out wet ball milling for 9 hours, and discharging to obtain a coating liquid precursor; in the preparation of the coating liquid precursor, the molar ratio of the carboxymethyl cellulose to the deionized water to the lithium carbonate to the vanadium pentoxide is 4:15:3: 1; the heating temperature is 60 ℃;
(3) depositing the coating liquid precursor prepared in the step (2) on the surface of the copper-magnesium doped nickel lithium phosphate material prepared in the step (1) through spray drying, then placing the material in a muffle furnace, presintering the material at 600 ℃ for 7.5h, and then heating the material to 720 ℃ to sinter the material for 2.5h to prepare Li3VO4a/C mixed coated copper-magnesium doped lithium nickel phosphate anode material; the spraying rotating speed of the spray drying is 16500r/min, and the diameter of the spraying disc is 135 mm; the weight ratio of the coating liquid precursor to the copper-magnesium doped lithium nickel phosphate material is 1.5: 10.
Comparative example 1
In the preparation process, the lithium nickel phosphate is not doped with metal ions, and other preparation conditions are the same as those of example 6.
Comparative example 2
In the preparation process, only the nickel lithium phosphate is coated by carbon, and Li is not used3VO4Mixed coating was performed and other preparation conditions were the same as in example 6.
And (3) performance testing:
(1) ionic conductivity: preparing the anode material prepared by the invention into an anode plate sample, measuring the ionic conductivity of the sample by using a four-probe method and a conductivity tester, and repeatedly testing and calculating the average value;
(2) and (3) testing specific capacity through charge and discharge circulation: the anode material prepared by the invention is prepared into an anode plate, a Celgard2400 polypropylene microporous membrane is used as a diaphragm, and 1mol/L LiPF6The button cell with the model number of CR2025 is assembled in a glove box filled with argon by taking a metal lithium sheet as an anode sheet and taking DMC =1:1 as an electrolyte, a battery performance testing system is adopted to carry out charge-discharge cycle testing, the charge-discharge Athens range is 2-4V, and the first charge-discharge specific capacity and the first cycle specific capacity under the multiplying power of 0.1C, 1C, 5C and 10C are respectively tested.
The data obtained are shown in Table 1.
Table 1: