Modified reinforced carbon black as well as preparation method and application thereof

Abstract

The invention provides modified reinforced carbon black as well as a preparation method and application thereof, and belongs to the technical field of energy storage materials of new energy batteries. The preparation method provided by the invention comprises the following steps: carrying out high-temperature treatment on N-series reinforced carbon black under the condition of air isolation to obtain modified reinforced carbon black; the temperature of the high-temperature treatment is 1500-2500 DEG C, and the time of the high-temperature treatment is 0.5-2 hours. According to the method, the N-series reinforced carbon black is subjected to high-temperature treatment under the condition of air isolation, and the temperature and time of high-temperature treatment are controlled, so that functional groups on the surface of the reinforced carbon black are removed, and meanwhile, the content of graphitized carbon is increased; further, when the obtained modified reinforced carbon black is used as a conductive agent in a battery, the cycle performance of the battery is basically close to the same level of commercial conductive carbon black superP, and the cost of the battery is greatly reduced.

Description

Technical Field

[0001] The present invention belongs to the technical field of new energy battery energy storage materials, and specifically relates to a modified reinforcing carbon black, a preparation method thereof, and an application thereof. Background Art

[0002] Clean energy sources such as solar energy, wind energy, and tidal energy have attracted much attention. However, these energy sources generally have the disadvantages of intermittency and discontinuity. Therefore, high-efficiency energy storage batteries have become the key solution to this problem. However, the positive and negative active materials of many batteries have poor conductivity themselves and are difficult to meet the requirements of high-performance batteries. Generally, conductive agents are added to improve the conductivity of the electrodes. In this context, conductive carbon black has become an indispensable key conductive agent in new energy batteries due to its excellent conductivity, good chemical stability, and other advantages. At present, high-performance conductive carbon black has high requirements for production processes and components, resulting in its high price, which limits its wide application in the field of large-scale energy storage. Therefore, how to reduce its cost without significantly reducing the performance of the conductive agent has become a difficult problem in this field. Summary of the Invention

[0003] The purpose of the present invention is to provide a modified reinforcing carbon black, a preparation method thereof, and an application thereof. By modifying the reinforcing carbon black, when the modified reinforcing carbon black is used as a conductive agent in a battery, the cycle performance of the battery is basically close to the same level as that of commercial conductive carbon black superP, and the cost of the battery is significantly reduced.

[0004] In order to achieve the above-mentioned invention purpose, the present invention provides the following technical solutions:

[0005] The present invention provides a preparation method of a modified reinforcing carbon black, including:

[0006] Performing high-temperature treatment on N-series reinforcing carbon black under the condition of air isolation to obtain modified reinforcing carbon black; the temperature of the high-temperature treatment is 1500-2500°C, and the time of the high-temperature treatment is 0.5-2h.

[0007] Preferably, the N-series reinforcing carbon black includes one or more of N-330 reinforcing carbon black, N-234 reinforcing carbon black, N-220 reinforcing carbon black, and N-115 reinforcing carbon black.

[0008] Preferably, the N-series reinforcing carbon black is ball-milled before the high-temperature treatment.

[0009] Preferably, the material-ball ratio of the ball milling is 1:(15-30), the rotation speed of the ball milling is 400-500r / min, and the time of the ball milling is 25-35min.

[0010] Preferably, the ratio of abrasive balls to materials in ball milling is 1:(20 - 30), the rotation speed of ball milling is 420 - 480 r / min, and the time of ball milling is 30 - 35 min.

[0011] Preferably, the temperature of the high-temperature treatment is 2000 - 2500 °C, and the time of the high-temperature treatment is 1 - 2 h.

[0012] Preferably, the heating rate for heating to the high-temperature treatment temperature is 4 - 6 °C / min.

[0013] Preferably, the heating rate for heating to the high-temperature treatment temperature is 5 °C / min.

[0014] The present invention also provides modified reinforcing carbon black prepared by the preparation method described in the above technical solution.

[0015] The present invention also provides the application of the modified reinforcing carbon black described in the above technical solution in a battery.

[0016] The present invention provides a preparation method of modified reinforcing carbon black, including: performing high-temperature treatment on N-series reinforcing carbon black under an air-insulated condition to obtain modified reinforcing carbon black; the temperature of the high-temperature treatment is 1500 - 2500 °C, and the time of the high-temperature treatment is 0.5 - 2 h. The present invention performs high-temperature treatment on N-series reinforcing carbon black under an air-insulated condition, controls the temperature and time of the high-temperature treatment, removes the functional groups on the surface of the reinforcing carbon black and improves the content of graphitized carbon therein, so that when the obtained modified reinforcing carbon black is used as a conductive agent in a battery, the cycle performance of the battery is basically close to the same level as that of commercial conductive carbon black superP, and the cost of the battery is greatly reduced. Description of the Drawings

[0017] Figure 1 is the charge-discharge curve of the battery in Application Example 1 at 0.5C;

[0018] Figure 2 is the charge-discharge curve of the battery in Comparative Application Example 1 at 0.5C;

[0019] Figure 3 is the charge-discharge curve of the battery in Comparative Application Example 4 at 0.5C;

[0020] Figure 4 is the cycle performance diagram of the batteries in Application Examples 1 - 3 and Comparative Application Examples 1 - 4 at 0.5C. Detailed Embodiments

[0021] The present invention provides a preparation method of modified reinforcing carbon black, including:

[0022] The N-series reinforcing carbon black is subjected to high-temperature treatment under air isolation conditions to obtain modified reinforcing carbon black; the temperature of the high-temperature treatment is 1500-2500 °C, and the time of the high-temperature treatment is 0.5-2 h.

[0023] In the present invention, the N-series reinforcing carbon black preferably includes one or more of N-330 reinforcing carbon black, N-234 reinforcing carbon black, N-220 reinforcing carbon black, and N-115 reinforcing carbon black.

[0024] In the present invention, the N-series reinforcing carbon black is preferably ball-milled before high-temperature treatment.

[0025] In the present invention, the material-to-ball ratio of the ball milling is preferably 1:(15-30); the rotation speed of the ball milling is preferably 400-500 r / min; the time of the ball milling is preferably 25-35 min. As an implementation manner, the material-to-ball ratio of the ball milling can specifically be 1:15, 1:18, 1:20, 1:22, 1:24, 1:26, 1:28, or 1:30; the rotation speed of the ball milling can specifically be 400 r / min, 410 r / min, 420 r / min, 430 r / min, 440 r / min, 450 r / min, 460 r / min, 470 r / min, 480 r / min, 490 r / min, or 500 r / min; the time of the ball milling can specifically be 25 min, 26 min, 27 min, 28 min, 29 min, 30 min, 31 min, 32 min, 33 min, 34 min, or 35 min. By performing ball milling in the present invention and controlling its parameters within the above ranges, the dispersibility of the N-series reinforcing carbon black can be improved, which is more conducive to subsequent high-temperature treatment.

[0026] In the present invention, the temperature of the high-temperature treatment is 1500-2500 °C; the time of the high-temperature treatment is 0.5-2 h. As an implementation manner, the temperature of the high-temperature treatment can specifically be 1500 °C, 1600 °C, 1800 °C, 2000 °C, 2200 °C, 2400 °C, or 2500 °C; the time of the high-temperature treatment can specifically be 0.5 h, 1 h, 1.5 h, or 2 h.

[0027] In the present invention, the heating rate for rising to the high-temperature treatment temperature is preferably 4-6 °C / min, and more preferably 5 °C / min.

[0028] In the present invention, the N series of reinforcing carbon black has more impurities and surface functional groups compared with conductive carbon black. These can cause side reactions during the charge and discharge process of the battery, increasing the interfacial impedance and thus affecting the performance of the battery. In the present invention, the N series of reinforcing carbon black is subjected to high-temperature treatment, and the temperature and time of the high-temperature treatment are controlled to remove the surface functional groups of the reinforcing carbon black while increasing the content of graphitized carbon. As a result, when the obtained modified reinforcing carbon black is used as a conductive agent in the battery, the cycle performance of the battery is basically close to the same level as that of the commercial conductive carbon black superP. The N series of reinforcing carbon black is inexpensive, thus greatly reducing the cost of the battery.

[0029] After the high-temperature treatment is completed, the present invention preferably cools the product after the high-temperature treatment to obtain modified reinforcing carbon black.

[0030] The present invention has no special limitation on the cooling operation, and it can be cooled to room temperature by using the cooling technical solutions well-known to those skilled in the art.

[0031] The present invention also provides the modified reinforcing carbon black prepared by the preparation method described in the above technical solution.

[0032] When the modified reinforcing carbon black prepared by the present invention is used as a conductive agent in the battery, the cycle performance of the battery is basically close to the same level as that of the commercial conductive carbon black superP.

[0033] The present invention also provides the application of the modified reinforcing carbon black described in the above technical solution in the battery.

[0034] The present invention has no special limitation on the application operation, and the technical solutions well-known to those skilled in the art can be used.

[0035] Next, the technical solutions in the present invention will be clearly and completely described in combination with the embodiments in the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments in the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope of protection of the present invention.

[0036] Example 1

[0037] A preparation method of modified reinforcing carbon black is as follows: The N-234 reinforcing carbon black is ball-milled in a planetary ball mill for 30 minutes, the material-to-ball ratio is 1:30, and the rotation speed is 450 r / min. Then, the ball-milled N-234 reinforcing carbon black is heated to 2500 °C at a heating rate of 5 °C / min in an airtight environment for 1 hour of high-temperature treatment, and then cooled to obtain modified reinforcing carbon black, denoted as modified N-234.

[0038] Example 2

[0039] Replace the N-234 reinforcing carbon black in Example 1 with N-330 reinforcing carbon black, and keep other parameters the same as those in Example 1 to obtain modified reinforcing carbon black, denoted as modified N-330.

[0040] Example 3

[0041] Replace the N-234 reinforcing carbon black in Example 1 with N-115 reinforcing carbon black, and keep other parameters the same as those in Example 1 to obtain modified reinforcing carbon black, denoted as modified N-115.

[0042] Application Example 1

[0043] Lithium iron phosphate (produced by Tianyuan), polyvinylidene fluoride, and the modified reinforcing carbon black prepared in Example 1 were ball-milled and dispersed at 400 r / min in N-methylpyrrolidone (solid content: 60%) according to a mass ratio of 8:1:1, and then coated on an aluminum foil to make a positive electrode plate, which was assembled into a half-cell for electrochemical cycling tests.

[0044] Application Example 2

[0045] Replace the modified reinforcing carbon black prepared in Example 1 in Application Example 1 with the modified reinforcing carbon black prepared in Example 2, and keep other parameters the same as those in Application Example 1.

[0046] Application Example 3

[0047] Replace the modified reinforcing carbon black prepared in Example 1 in Application Example 1 with the modified reinforcing carbon black prepared in Example 3, and keep other parameters the same as those in Application Example 1.

[0048] Comparative Application Example 1

[0049] Replace the modified reinforcing carbon black prepared in Example 1 in Application Example 1 with the N-234 reinforcing carbon black in Example 1, and keep other parameters the same as those in Application Example 1.

[0050] Comparative Application Example 2

[0051] Replace the modified reinforcing carbon black prepared in Example 2 in Application Example 2 with the N-330 reinforcing carbon black in Example 2, and keep other parameters the same as those in Application Example 2.

[0052] Comparative Application Example 3

[0053] Replace the modified reinforcing carbon black prepared in Example 3 in Application Example 3 with the N-115 reinforcing carbon black in Example 3, and keep other parameters the same as those in Application Example 3.

[0054] Comparative Application Example 4

[0055] Replace the modified reinforcing carbon black prepared in Example 1 in Application Example 1 with super P conductive carbon black, and keep other parameters the same as those in Application Example 1.

[0056] The charge-discharge curves of the battery in Application Example 1 at 0.5C are as Figure 1 shown. The charge-discharge curves of the battery in Application Example 1 at 0.5C are as Figure 2 shown. The charge-discharge curves of the battery in Comparative Application Example 4 at 0.5C are as Figure 3 shown.

[0057] The cycle performance of the batteries in Application Examples 1-3 and Comparative Application Examples 1-4 at 0.5C is as Figure 4 shown, and the cycle capacity retention rate after 200 cycles is shown in Table 1.

[0058] Table 1 Cycle capacity retention rate of the batteries in Application Examples 1-3 and Comparative Application Examples 1-4 at 0.5C after 200 cycles

[0059] Retention rate of capacity after 200 cycles Application Example 1 (modified N-234) 88％ Comparative Application Example 1 (N-234) 22％ Application Example 2 (modified N-330) 80.7％ Comparative Application Example 2 (N-330) 21.8％ Application Example 3 (modified N-115) 72％ Comparative Application Example 3 (N-115) 3.8％ Comparative Application Example 4 (superP conductive carbon black) 93％

[0060] From Figures 1 to 4 and Table 1, it can be seen that the performance of the battery assembled with the modified reinforcing carbon black by the method of the present invention is significantly improved compared with that before modification, and the effect is basically close to the same level of superP within 200 cycles.

[0061] In summary, by modifying the reinforcing carbon black, the present invention enables the obtained modified reinforcing carbon black to be used as a conductive agent in the battery, so that the cycle performance of the battery is basically close to the same level of the commercial conductive carbon black superP. The cost of the reinforcing carbon black is less than 20,000 yuan per ton, while the cost of the superP conductive carbon black is more than 45,000 yuan per ton. The solution of the present invention greatly reduces the cost of the battery.

[0062] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the principle of the present invention, several improvements and refinements can still be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A preparation method of modified reinforcing carbon black, comprising: Performing high-temperature treatment on N series reinforcing carbon black under the condition of air isolation to obtain modified reinforcing carbon black; The temperature of the high-temperature treatment is 1500-2500 °C, and the time of the high-temperature treatment is 0.5-2 h.

2. The preparation method according to claim 1, wherein The N series reinforcing carbon black includes one or more of N-330 reinforcing carbon black, N-234 reinforcing carbon black, N-220 reinforcing carbon black and N-115 reinforcing carbon black.

3. The preparation method according to claim 1, wherein The N series reinforcing carbon black is ball-milled before the high-temperature treatment.

4. The preparation method according to claim 3, characterized in that, The material-ball ratio of the ball milling is 1:(15-30), the rotation speed of the ball milling is 400-500 r / min, and the time of the ball milling is 25-35 min.

5. The preparation method according to claim 4, characterized in that, The material-ball ratio of the ball milling is 1:(20-30), the rotation speed of the ball milling is 420-480 r / min, and the time of the ball milling is 30-35 min.

6. The preparation method according to claim 1, wherein, The temperature of the high-temperature treatment is 2000-2500 °C, and the time of the high-temperature treatment is 1-2 h.

7. The preparation method according to claim 1, wherein The heating rate to the high-temperature treatment temperature is 4-6 °C / min.

8. The preparation method according to claim 7, wherein The heating rate to the high-temperature treatment temperature is 5 °C / min.

9. The modified reinforcing carbon black prepared by the preparation method according to any one of claims 1-8.

10. Application of the modified reinforcing carbon black according to claim 9 in a battery.

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