New energy lithium battery material and preparation method thereof

Abstract

The application relates to the technical field of battery materials, in particular to a new energy lithium battery material and a preparation method thereof, which comprises the following steps: preheating lithium iron phosphate at 65-70 DEG C for 1 h to obtain preheated lithium iron phosphate; stirring and treating the preheated lithium iron phosphate and a carbon nanotube modification liquid according to a weight ratio of 3:(5-8) to obtain carbon nanotube modified lithium iron phosphate liquid. The new energy lithium battery material adopts lithium iron phosphate which is preheated, then is stirred and treated in cooperation with a carbon nanotube modification liquid, and then is treated through continuous B-La dopant and fiber reinforcing liquid for ball milling and mixing for the second time, so that the specific capacity, the first efficiency performance and the cycle capacity retention rate performance of the obtained new energy lithium battery material are excellent, and the cycle stability of the product is remarkably improved under the conditions of multiple cycles, high-temperature resistance and low-temperature resistance.

Description

Technical Field

[0001] This invention relates to the field of battery materials technology, specifically to a new energy lithium battery material and its preparation method. Background Technology

[0002] Lithium-ion batteries are widely used in new energy vehicles, portable electronic devices, and energy storage systems due to their high energy density, long cycle life, and environmental friendliness. With the rapid development of the new energy industry, higher requirements are being placed on the energy density, cycle stability, and safety of lithium batteries. The cathode material is one of the most critical components of a lithium-ion battery, and its performance directly restricts the overall performance of the battery. Currently, the most common cathode materials used in lithium-ion batteries include lithium cobalt oxide (LiCoO2), lithium manganese oxide (LiMn2O4), lithium iron phosphate (LiFePO4), and ternary materials. Existing lithium battery materials exhibit poor specific capacity, initial efficiency, and cycle capacity retention. Furthermore, their cycle stability is poor under repeated cycles, high and low temperature conditions, limiting their overall efficiency. Therefore, this invention provides further improvements to these materials. Summary of the Invention

[0003] In view of the shortcomings of the prior art, the purpose of this invention is to provide a new energy lithium battery material and its preparation method to solve the problems mentioned in the background art.

[0004] The present invention solves the technical problem by adopting the following technical solution: This invention provides a method for preparing new energy lithium battery materials, comprising the following steps: Step 1: Preheat lithium iron phosphate at 65~70℃ for 1 hour to obtain preheated lithium iron phosphate. Stir the preheated lithium iron phosphate and carbon nanotube modified liquid at a weight ratio of 3:(5~8) to obtain carbon nanotube modified lithium iron phosphate liquid. Step 2: The carbon nanotube-modified lithium iron phosphate solution and B-La dopant are ball-milled and adjusted at a weight ratio of (8~11):5. After ball milling, the solution is filtered and dried to obtain the B-La-modified lithium iron phosphate body. Step 3: The B-La compounded lithium iron phosphate body and fiber reinforcing liquid are ball-milled at a weight ratio of (11~15):7. After ball milling, the mixture is filtered and dried to obtain the new energy lithium battery material.

[0005] Preferably, the stirring speed for the stirring process is 550~650 r / min, and the stirring time is 2 hours; The ball milling speed for the first adjustment treatment was 750~850 r / min, and the ball milling time was 2 hours; the ball milling speed for the second adjustment treatment was 1150~1250 r / min, and the ball milling time was 1 hour.

[0006] Preferably, the preparation method of the carbon nanotube modified liquid is as follows: S01: Stir carbon nanotubes thoroughly in a sufficient amount of potassium permanganate solution with a mass fraction of 5-8%, then wash with water, filter, and dry. Preheat the dried carbon nanotubes at 135-145℃ for 1-1.5h, and then cool them to 60℃ at a rate of 2-5℃ / min. Keep them warm to obtain heat-insulated carbon nanotubes. SO2: 5-8 parts of heat-insulating carbon nanotubes, 6-10 parts of sodium dodecylbenzenesulfonate solution, 1-2 parts of silane coupling agent KH550 and 3-5 parts of alumina are thoroughly mixed to obtain a carbon nanotube modified solution.

[0007] Preferably, the sodium dodecylbenzenesulfonate solution has a mass fraction of 10-15%.

[0008] Preferably, the B-La dopant is prepared by: S11, β-cyclodextrin, 75-85% ethanol aqueous solution and silane coupling agent KH560 are mixed evenly in a weight ratio of (3-5):7:(1-3) to obtain β-cyclodextrin solution; Nano-titanium dioxide was irradiated in a proton irradiation chamber for 1 hour at an irradiation power of 350-400W. After irradiation, irradiated nano-titanium dioxide was obtained. 4-7 parts of irradiated nano-titanium dioxide and 10-15 parts of β-cyclodextrin solution were mixed evenly to obtain nano-titanium dioxide-β-cyclodextrin complex solution. S12, Preparation of hybrid blending solution: S12a, nano-bismuth oxide, zirconium oxide and 10% sodium citrate solution are mixed evenly in a weight ratio of (3~5):(2~3):7 to obtain an impregnation solution; S12b involves immersing graphene in an impregnation solution that is 5 to 8 times the total amount of graphene. After impregnation, the solution is filtered and dried to obtain the impregnated graphene agent. S12c, the impregnated graphene agent and nano titanium dioxide-β-cyclodextrin complex solution are stirred at a weight ratio of (5~8):13. After stirring, a hybrid mixture is obtained. S13, hybrid blending solution and B-La blending agent are ball-milled at a weight ratio of (11~14):5, ball milling speed is 1050~1150 r / min, ball milling for 2 h, after ball milling is completed, filter and dry to obtain B-La dopant.

[0009] Preferably, the impregnation ultrasonic power of the impregnation treatment is 550~600W, and the impregnation time is 1h; the stirring speed of the stirring treatment in S12c is 350~400r / min, and the stirring time is 35~45min.

[0010] Preferably, the preparation method of the B-La modifier is as follows: Mix 3-5 parts boron oxide, 2-4 parts lanthanum oxide and 7-11 parts sodium lignosulfonate solution evenly, then add 2-4 parts zinc oxide whiskers and 1-2 parts urea solution, mix thoroughly, and finally filter and dry to obtain B-La additive.

[0011] Preferably, the urea solution has a mass fraction of 2-5%; the sodium lignosulfonate solution has a mass fraction of 5-8%.

[0012] Preferably, the fiber reinforcing liquid is prepared by mixing 4-7 parts of carbon fiber, 3-5 parts of kaolin, 5-8 parts of sodium silicate solution with a mass fraction of 4-7% and 1-2 parts of sodium carboxymethyl cellulose thoroughly to obtain the fiber reinforcing liquid.

[0013] This invention also provides a method for preparing new energy lithium battery materials.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. The new energy lithium battery material of this invention uses lithium iron phosphate that has been preheated and then stirred with carbon nanotube modified liquid. It is then subjected to ball milling first and second conditioning treatments with B-La dopant and fiber reinforcing liquid. The resulting new energy lithium battery material has excellent specific capacity, initial efficiency and cycle capacity retention. At the same time, the product has significant cycle stability under multiple cycles, high temperature and low temperature conditions. Carbon nanotube modification optimizes the material's conductivity and ion transport efficiency, while B-La dopant regulates the crystal structure and reduces defects. The synergistic effect of these two components results in a higher specific capacity than traditional lithium iron phosphate, with a significant improvement in initial charge-discharge efficiency. Graphene and nano-titanium dioxide in the B-La dopant form a stable framework, suppressing volume expansion and structural collapse during cycling. After multiple cycles, the capacity decay rate decreases, and the retention rate is greatly improved. Carbon fibers and kaolin in the fiber reinforcing liquid further enhance the material's structural stability. Combined with the synergistic protection of B-La doping, stable cycling performance can be maintained under high and low temperature environments, broadening the operating temperature range. 2. The lithium iron phosphate precursor is first improved by carbon nanotube modification solution. The carbon nanotubes in the carbon nanotube modification solution are activated by potassium permanganate solution and then thermally modified to optimize their activity. Then, sodium dodecylbenzene sulfonate solution, silane coupling agent KH550 and alumina are mixed. Through the mutual assistance and synergy of the raw materials, the interfacial connectivity of the lithium iron phosphate precursor is optimized and it is easier to carry out continuous ball milling improvement in the future, thereby optimizing the overall effect of the product. 3. The B-La dopant is prepared by ball milling using a hybrid blending solution and a B-La incorporating agent. The graphene in the hybrid blending solution is impregnated with an impregnation solution, which allows for the doping of nano-bismuth oxide and zirconium oxide components, facilitating better integration into the system and improving system performance. Meanwhile, the nano-titanium dioxide-β-cyclodextrin complexing solution is prepared by irradiating nano-titanium dioxide to activate its activity, and then improving and optimizing it with β-cyclodextrin solution. The β-cyclodextrin, 75-85% ethanol aqueous solution, and silane coupling agent KH560 in the β-cyclodextrin solution are mutually blended and synergistic, enhancing the synergistic effect between β-cyclodextrin solution and nano-titanium dioxide. The resulting hybrid blending solution further enhances the performance of the system. 4. The B-La additive uses boron oxide and lanthanum oxide dispersed in sodium lignosulfonate solution and then blended with zinc oxide whiskers and urea solution. The zinc oxide whiskers carry the boron oxide and lanthanum oxide raw materials in a whisker structure, thereby reinforcing the system and further enhancing the system's performance. 5. The fiber reinforcing liquid adopts the needle-like structure of carbon fiber, blended with the layered structure of kaolin, and blended and optimized with sodium silicate solution and sodium carboxymethyl cellulose. Through the co-processing of raw materials, the system structure is further reinforced, thereby optimizing and improving the system performance and resulting in further enhanced product performance. Detailed Implementation

[0015] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to specific examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0016] This embodiment describes a method for preparing a new energy lithium battery material, including the following steps: Step 1: Preheat lithium iron phosphate at 65~70℃ for 1 hour to obtain preheated lithium iron phosphate. Stir the preheated lithium iron phosphate and carbon nanotube modified liquid at a weight ratio of 3:(5~8) to obtain carbon nanotube modified lithium iron phosphate liquid. Step 2: The carbon nanotube-modified lithium iron phosphate solution and B-La dopant are ball-milled and adjusted at a weight ratio of (8~11):5. After ball milling, the solution is filtered and dried to obtain the B-La-modified lithium iron phosphate body. Step 3: The B-La compounded lithium iron phosphate body and fiber reinforcing liquid are ball-milled at a weight ratio of (11~15):7. After ball milling, the mixture is filtered and dried to obtain the new energy lithium battery material.

[0017] In this embodiment, the stirring speed is 550~650 r / min, and the stirring time is 2 hours. The ball milling speed for the first adjustment treatment was 750~850 r / min, and the ball milling time was 2 hours; the ball milling speed for the second adjustment treatment was 1150~1250 r / min, and the ball milling time was 1 hour.

[0018] The preparation method of the carbon nanotube modified liquid in this embodiment is as follows: S01: Stir carbon nanotubes thoroughly in a sufficient amount of potassium permanganate solution with a mass fraction of 5-8%, then wash with water, filter, and dry. Preheat the dried carbon nanotubes at 135-145℃ for 1-1.5h, and then cool them to 60℃ at a rate of 2-5℃ / min. Keep them warm to obtain heat-insulated carbon nanotubes. SO2: 5-8 parts of heat-insulating carbon nanotubes, 6-10 parts of sodium dodecylbenzenesulfonate solution, 1-2 parts of silane coupling agent KH550 and 3-5 parts of alumina are thoroughly mixed to obtain a carbon nanotube modified solution.

[0019] The sodium dodecylbenzenesulfonate solution in this embodiment has a mass fraction of 10-15%.

[0020] The preparation method of the B-La dopant in this embodiment is as follows: S11, β-cyclodextrin, 75-85% ethanol aqueous solution and silane coupling agent KH560 are mixed evenly in a weight ratio of (3-5):7:(1-3) to obtain β-cyclodextrin solution; Nano-titanium dioxide was irradiated in a proton irradiation chamber for 1 hour at an irradiation power of 350-400W. After irradiation, irradiated nano-titanium dioxide was obtained. 4-7 parts of irradiated nano-titanium dioxide and 10-15 parts of β-cyclodextrin solution were mixed evenly to obtain nano-titanium dioxide-β-cyclodextrin complex solution. S12, Preparation of hybrid blending solution: S12a, nano-bismuth oxide, zirconium oxide and 10% sodium citrate solution are mixed evenly in a weight ratio of (3~5):(2~3):7 to obtain an impregnation solution; S12b involves immersing graphene in an impregnation solution that is 5 to 8 times the total amount of graphene. After impregnation, the solution is filtered and dried to obtain the impregnated graphene agent. S12c, the impregnated graphene agent and nano titanium dioxide-β-cyclodextrin complex solution are stirred at a weight ratio of (5~8):13. After stirring, a hybrid mixture is obtained. S13, hybrid blending solution and B-La blending agent are ball-milled at a weight ratio of (11~14):5, ball milling speed is 1050~1150 r / min, ball milling for 2 h, after ball milling is completed, filter and dry to obtain B-La dopant.

[0021] In this embodiment, the immersion ultrasonic power for the immersion treatment is 550~600W, and the immersion time is 1h; the stirring speed for the stirring treatment in S12c is 350~400r / min, and the stirring time is 35~45min.

[0022] The preparation method of the B-La modifier in this embodiment is as follows: Mix 3-5 parts boron oxide, 2-4 parts lanthanum oxide and 7-11 parts sodium lignosulfonate solution evenly, then add 2-4 parts zinc oxide whiskers and 1-2 parts urea solution, mix thoroughly, and finally filter and dry to obtain B-La additive.

[0023] In this embodiment, the urea solution has a mass fraction of 2-5%; the sodium lignosulfonate solution has a mass fraction of 5-8%.

[0024] The fiber reinforcing liquid in this embodiment is prepared by mixing 4-7 parts of carbon fiber, 3-5 parts of kaolin, 5-8 parts of sodium silicate solution with a mass fraction of 4-7% and 1-2 parts of sodium carboxymethyl cellulose thoroughly to obtain the fiber reinforcing liquid.

[0025] This embodiment describes a method for preparing new energy lithium battery materials.

[0026] Example 1. This embodiment describes a method for preparing a new energy lithium battery material, including the following steps: Step 1: Preheat lithium iron phosphate at 65℃ for 1 hour to obtain preheated lithium iron phosphate. Stir the preheated lithium iron phosphate and carbon nanotube modified liquid at a weight ratio of 3:5 to obtain carbon nanotube modified lithium iron phosphate liquid. Step 2: The carbon nanotube-modified lithium iron phosphate solution and B-La dopant are ball-milled and mixed at a weight ratio of 8:5. After ball milling, the mixture is filtered and dried to obtain the B-La-modified lithium iron phosphate body. Step 3: The B-La compounded lithium iron phosphate body and fiber reinforcing liquid are ball-milled at a weight ratio of 11:7 for secondary conditioning. After ball milling, the mixture is filtered and dried to obtain the new energy lithium battery material.

[0027] In this embodiment, the stirring speed is 550 r / min, and the stirring time is 2 h. The ball milling process for the first adjustment was carried out at a speed of 750 r / min for 2 hours; the ball milling process for the second adjustment was carried out at a speed of 1150 r / min for 1 hour.

[0028] The preparation method of the carbon nanotube modified liquid in this embodiment is as follows: S01: Carbon nanotubes are stirred thoroughly in a sufficient amount of 5% potassium permanganate solution, then washed with water, filtered, and dried. The dried carbon nanotubes are preheated at 135℃ for 1 hour, and then cooled to 60℃ at a rate of 2℃ / min and kept at the temperature to obtain heat-insulated carbon nanotubes. SO2: 5 parts of heat-insulating carbon nanotubes, 6 parts of sodium dodecylbenzenesulfonate solution, 1 part of silane coupling agent KH550 and 3 parts of alumina are thoroughly mixed to obtain a carbon nanotube modified solution.

[0029] The sodium dodecylbenzenesulfonate solution in this embodiment has a mass fraction of 10%.

[0030] The preparation method of the B-La dopant in this embodiment is as follows: S11, β-cyclodextrin, 75% ethanol aqueous solution and silane coupling agent KH560 are mixed evenly in a weight ratio of 3:7:1 to obtain β-cyclodextrin solution; Nano-titanium dioxide was irradiated in a proton irradiation chamber for 1 hour at an irradiation power of 350W. After irradiation, irradiated nano-titanium dioxide was obtained. Four parts of irradiated nano-titanium dioxide and ten parts of β-cyclodextrin solution were mixed evenly to obtain nano-titanium dioxide-β-cyclodextrin complex solution. S12, Preparation of hybrid blending solution: S12a, nano-bismuth oxide, zirconium oxide and 10% sodium citrate solution are mixed evenly in a weight ratio of 3:2:7 to obtain an impregnation solution; S12b involves immersing graphene in an impregnation solution five times the total amount of graphene for impregnation treatment. After impregnation, the solution is filtered and dried to obtain the impregnated graphene agent. S12c, the impregnated graphene agent and nano titanium dioxide-β-cyclodextrin complex solution are stirred at a weight ratio of 5:13. After stirring, a hybrid mixture is obtained. S13, the hybrid blending solution and B-La dopant were ball-milled at a weight ratio of 11:5 at a speed of 1050 r / min for 2 h. After ball milling, the mixture was filtered and dried to obtain the B-La dopant.

[0031] In this embodiment, the immersion ultrasonic power for the immersion treatment is 5500W, and the immersion time is 1 hour; the stirring speed for the stirring treatment in S12c is 3500 r / min, and the stirring time is 35 min.

[0032] The preparation method of the B-La modifier in this embodiment is as follows: Three parts boron oxide, two parts lanthanum oxide and seven parts sodium lignosulfonate solution were mixed evenly, then two parts zinc oxide whiskers and one part urea solution were added and mixed thoroughly. Finally, the mixture was filtered and dried to obtain B-La additive.

[0033] In this embodiment, the urea solution has a mass fraction of 2% and the sodium lignosulfonate solution has a mass fraction of 5%.

[0034] The fiber reinforcing liquid in this embodiment is prepared by mixing 4 parts carbon fiber, 3 parts kaolin, 5 parts sodium silicate solution with a mass fraction of 4% and 1 part sodium carboxymethyl cellulose thoroughly to obtain the fiber reinforcing liquid.

[0035] This embodiment describes a method for preparing new energy lithium battery materials.

[0036] Example 2. This embodiment describes a method for preparing a new energy lithium battery material, including the following steps: Step 1: Preheat lithium iron phosphate at 70℃ for 1 hour to obtain preheated lithium iron phosphate. Stir the preheated lithium iron phosphate and carbon nanotube modified liquid at a weight ratio of 3:8 to obtain carbon nanotube modified lithium iron phosphate liquid. Step 2: The carbon nanotube-modified lithium iron phosphate solution and B-La dopant are ball-milled and adjusted at a weight ratio of 11:5. After ball milling, the solution is filtered and dried to obtain the B-La-modified lithium iron phosphate body. Step 3: The B-La compounded lithium iron phosphate body and fiber reinforcing liquid are ball-milled at a weight ratio of 15:7 for secondary conditioning. After ball milling, the mixture is filtered and dried to obtain the new energy lithium battery material.

[0037] In this embodiment, the stirring speed is 650 r / min, and the stirring time is 2 h. The ball milling process for the first adjustment was carried out at a speed of 850 r / min for 2 hours; the ball milling process for the second adjustment was carried out at a speed of 1250 r / min for 1 hour.

[0038] The preparation method of the carbon nanotube modified liquid in this embodiment is as follows: S01: Carbon nanotubes are stirred thoroughly in a sufficient amount of 8% potassium permanganate solution, then washed with water, filtered, and dried. The dried carbon nanotubes are preheated at 145℃ for 1.5h, and then cooled to 60℃ at a rate of 5℃ / min and kept at the temperature to obtain heat-insulated carbon nanotubes. SO2: 8 parts of heat-insulating carbon nanotubes, 10 parts of sodium dodecylbenzenesulfonate solution, 2 parts of silane coupling agent KH550 and 5 parts of alumina are thoroughly mixed to obtain carbon nanotube modified solution.

[0039] The sodium dodecylbenzenesulfonate solution in this embodiment has a mass fraction of 15%.

[0040] The preparation method of the B-La dopant in this embodiment is as follows: S11, β-cyclodextrin, 75-85% ethanol aqueous solution and silane coupling agent KH560 are mixed evenly in a weight ratio of 5:7:3 to obtain β-cyclodextrin solution; Nano-titanium dioxide was irradiated in a proton irradiation chamber for 1 hour at an irradiation power of 400W. After irradiation, irradiated nano-titanium dioxide was obtained. Seven parts of irradiated nano-titanium dioxide and 15 parts of β-cyclodextrin solution were mixed evenly to obtain nano-titanium dioxide-β-cyclodextrin complex solution. S12, Preparation of hybrid blending solution: S12a, nano-bismuth oxide, zirconium oxide and 10% sodium citrate solution are mixed evenly in a weight ratio of 5:3:7 to obtain an impregnation solution; S12b involves immersing graphene in an impregnation solution equal to eight times the total amount of graphene. After impregnation, the solution is filtered and dried to obtain the impregnated graphene agent. S12c, the impregnated graphene agent and nano titanium dioxide-β-cyclodextrin complex solution are stirred at a weight ratio of 8:13. After stirring, a hybrid mixture is obtained. S13, the hybrid blending solution and B-La dopant were ball-milled at a weight ratio of 14:5 at a speed of 1150 r / min for 2 h. After ball milling, the mixture was filtered and dried to obtain the B-La dopant.

[0041] In this embodiment, the immersion ultrasonic power for the immersion treatment is 600W, and the immersion time is 1 hour; the stirring speed for the stirring treatment in S12c is 400 r / min, and the stirring time is 45 min.

[0042] The preparation method of the B-La modifier in this embodiment is as follows: Five parts boron oxide, four parts lanthanum oxide and eleven parts sodium lignosulfonate solution were mixed evenly, then four parts zinc oxide whiskers and two parts urea solution were added and mixed thoroughly. Finally, the mixture was filtered and dried to obtain B-La additive.

[0043] In this embodiment, the urea solution has a mass fraction of 5%, and the sodium lignosulfonate solution has a mass fraction of 8%.

[0044] The fiber reinforcing liquid in this embodiment is prepared by mixing 7 parts carbon fiber, 5 parts kaolin, 8 parts sodium silicate solution with a mass fraction of 7% and 2 parts sodium carboxymethyl cellulose thoroughly to obtain the fiber reinforcing liquid.

[0045] This embodiment describes a method for preparing new energy lithium battery materials.

[0046] Example 3. This embodiment describes a method for preparing a new energy lithium battery material, including the following steps: Step 1: Preheat lithium iron phosphate at 67.5℃ for 1 hour to obtain preheated lithium iron phosphate. Stir the preheated lithium iron phosphate and carbon nanotube modified liquid at a weight ratio of 3:6.5 to obtain carbon nanotube modified lithium iron phosphate liquid. Step 2: The carbon nanotube-modified lithium iron phosphate solution and B-La dopant are ball-milled and adjusted at a weight ratio of 9:5. After ball milling, the solution is filtered and dried to obtain the B-La-modified lithium iron phosphate body. Step 3: The B-La compounded lithium iron phosphate body and fiber reinforcing liquid are ball-milled at a weight ratio of 13:7 for secondary conditioning. After ball milling, the mixture is filtered and dried to obtain the new energy lithium battery material.

[0047] In this embodiment, the stirring speed is 600 r / min, and the stirring time is 2 hours. The ball milling process for the first adjustment was carried out at a speed of 800 r / min for 2 hours; the ball milling process for the second adjustment was carried out at a speed of 1200 r / min for 1 hour.

[0048] The preparation method of the carbon nanotube modified liquid in this embodiment is as follows: S01: Carbon nanotubes are stirred thoroughly in a sufficient amount of 6.5% potassium permanganate solution, then washed with water, filtered, and dried. The dried carbon nanotubes are preheated at 140℃ for 1.25h, and then cooled to 60℃ at a rate of 3.5℃ / min and kept at the temperature to obtain heat-insulated carbon nanotubes. SO2: 6.5 parts of heat-insulating carbon nanotubes, 8 parts of sodium dodecylbenzenesulfonate solution, 1.5 parts of silane coupling agent KH550 and 4 parts of alumina are thoroughly mixed to obtain carbon nanotube modified solution.

[0049] The sodium dodecylbenzenesulfonate solution in this embodiment has a mass fraction of 12.5%.

[0050] The preparation method of the B-La dopant in this embodiment is as follows: S11, β-cyclodextrin, 80% ethanol aqueous solution and silane coupling agent KH560 are mixed evenly in a weight ratio of 4:7:2 to obtain β-cyclodextrin solution; Nano-titanium dioxide was irradiated in a proton irradiation chamber for 1 hour at an irradiation power of 370W. After irradiation, irradiated nano-titanium dioxide was obtained. 5.5 parts of irradiated nano-titanium dioxide and 12.5 parts of β-cyclodextrin solution were mixed evenly to obtain nano-titanium dioxide-β-cyclodextrin complex solution. S12, Preparation of hybrid blending solution: S12a, nano-bismuth oxide, zirconium oxide and 10% sodium citrate solution are mixed evenly in a weight ratio of 4:2.5:7 to obtain an impregnation solution; S12b involves immersing graphene in an impregnation solution equal to 6.5 times the total amount of graphene. After impregnation, the solution is filtered and dried to obtain the impregnated graphene agent. S12c, the impregnated graphene agent and nano titanium dioxide-β-cyclodextrin complex solution were stirred at a weight ratio of 6.5:13. After stirring, a hybrid mixture was obtained. S13, the hybrid blending solution and B-La dopant were ball-milled at a weight ratio of 13:5 at a speed of 1100 r / min for 2 h. After ball milling, the mixture was filtered and dried to obtain the B-La dopant.

[0051] In this embodiment, the immersion ultrasonic power for the immersion treatment is 575W, and the immersion time is 1 hour; the stirring speed for the stirring treatment in S12c is 370 r / min, and the stirring time is 40 min.

[0052] The preparation method of the B-La modifier in this embodiment is as follows: Four parts boron oxide, three parts lanthanum oxide and nine parts sodium lignosulfonate solution were mixed evenly, then three parts zinc oxide whiskers and 1.5 parts urea solution were added and mixed thoroughly. Finally, the mixture was filtered and dried to obtain B-La additive.

[0053] In this embodiment, the urea solution has a mass fraction of 3.5% and the sodium lignosulfonate solution has a mass fraction of 6.5%.

[0054] The fiber reinforcing liquid in this embodiment is prepared by mixing 5.5 parts of carbon fiber, 4 parts of kaolin, 6.5 parts of sodium silicate solution with a mass fraction of 5.5% and 1.5 parts of sodium carboxymethyl cellulose thoroughly to obtain the fiber reinforcing liquid.

[0055] This embodiment describes a method for preparing new energy lithium battery materials.

[0056] Comparative Example 1. Unlike Example 3, no carbon nanotube modification liquid was added.

[0057] Comparative Example 2. Unlike Example 3, no heat-insulating carbon nanotubes and alumina were added in the preparation of the carbon nanotube modified liquid.

[0058] Comparative Example 3. Unlike Example 3, no B-La dopant was added.

[0059] Comparative Example 4. Unlike Example 3, no hybridization solution was added during the preparation of the B-La dopant.

[0060] Comparative Example 5. Unlike Example 3, no impregnating graphene agent was added to the hybrid blending solution.

[0061] Comparative Example 6. Unlike Example 3, no impregnation solution was added during the preparation of the impregnated graphene agent.

[0062] Comparative Example 7. Unlike Example 3, no graphene was added to the impregnated graphene agent.

[0063] Comparative Example 8. Unlike Example 3, the hybrid blending solution did not contain nano-titanium dioxide-β-cyclodextrin blending solution.

[0064] Comparative Example 9. Unlike Example 3, no irradiated nano-titanium dioxide and β-cyclodextrin were added to the nano-titanium dioxide-β-cyclodextrin complex solution.

[0065] Comparative Example 10. Unlike Example 3, no B-La incorporator was added during the preparation of the B-La dopant.

[0066] Comparative Example 11. Unlike Example 3, no fiber reinforcing liquid was added.

[0067] Comparative Example 12. Unlike Example 3, carbon fiber and kaolin were not added in the preparation of the fiber reinforcing liquid.

[0068] Using the products of Examples 1-3 and Comparative Examples 1-12 as positive electrode materials, and graphite as negative electrode, soft-pack batteries were assembled and their electrical performance was tested using a battery performance tester. The charge / discharge cutoff voltage was 34.45V. The batteries underwent specific capacity and initial efficiency performance tests, as well as cycle capacity retention tests. The cycle stability of the batteries was also tested under multiple cycles, high temperature (batteries placed at 75°C for 48 hours), and low temperature (batteries placed at -20°C for 48 hours). The test results are as follows. As can be seen from Comparative Examples 1-12 and Examples 1-3; The product in Example 3 exhibits excellent battery specific capacity and initial efficiency performance, as well as excellent cycle capacity retention stability. The product demonstrates significant stability in cycle capacity retention under multiple cycles, high temperature resistance, and low temperature resistance conditions. Without the addition of B-La dopant, fiber reinforcing liquid, and carbon nanotube modification liquid, the product's performance showed a significant downward trend. In particular, without the addition of B-La dopant, the product's performance deteriorated significantly. The most significant performance improvement was achieved by combining B-La dopant, fiber reinforcing liquid, and carbon nanotube modification liquid in combination. In the preparation of B-La dopants, no hybrid mixing solution was added; no impregnating graphene agent was added to the hybrid mixing solution; no impregnating solution was added to the impregnating graphene agent; no graphene was added to the impregnating graphene agent; no nano-titanium dioxide-β-cyclodextrin complex mixture was added to the hybrid mixing solution; no irradiated nano-titanium dioxide and β-cyclodextrin were added to the nano-titanium dioxide-β-cyclodextrin complex mixture; and no B-La incorporating agent was added in the preparation of B-La dopants. The performance of the products all showed a deterioration trend to varying degrees. In particular, the performance of the product deteriorates significantly when B-La dopant preparation is not made by adding B-La modifier. The hybrid blending liquid obtained by the specific method of this invention has the best performance. The preparation of the hybrid blending liquid is unique. Only the hybrid blending liquid obtained by using the graphene impregnation agent of this invention in combination with nano-titanium dioxide-β-cyclodextrin complex blending liquid has the most obvious performance. Meanwhile, the carbon nanotube modified liquid and alumina were not added for heat preservation in the preparation of the carbon nanotube modified liquid, and carbon fiber and kaolin were not added in the preparation of the fiber reinforcing liquid. As a result, the performance of the products also showed a deterioration trend. The preparation of the carbon nanotube modified liquid and the fiber reinforcing liquid of the present invention are unique.

[0069] This invention further explores the performance of the product through the preparation of B-La modifier; Experimental Example 1. Same as Example 3, except that boron oxide was not added in the preparation of the B-La conditioning agent.

[0070] Experimental Example 2. Same as Example 3, except that lanthanum oxide was not added in the preparation of the B-La conditioning agent.

[0071] Experimental Example 3. Same as Example 3, except that zinc oxide whiskers were not added in the preparation of B-La conditioning agent.

[0072] Experimental Example 4. Same as Example 3, except that urea solution was not added in the preparation of B-La conditioning agent, and water was used instead of sodium lignosulfonate solution.

[0073] The present invention conducted further performance tests on the products of Experimental Examples 1-4, and the test results are as follows: As can be seen from Experiments 1-4, the absence of zinc oxide whiskers in the preparation of B-La additives resulted in the most significant deterioration in product performance among the factors affecting B-La additive preparation. The absence of boron oxide, lanthanum oxide, urea solution, and the substitution of water for sodium lignosulfonate solution all led to a deterioration in product performance. Only the B-La additive prepared using the specific method of this invention exhibited the most significant performance improvement. In the preparation of B-La additives, all raw materials are indispensable; only the specific raw material ratios of this invention are used. Using other raw material ratios does not yield the same significant results as this invention.

[0074] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the invention. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, it is intended that all variations falling within the meaning and scope of equivalents of the claims be included within the present invention.

[0075] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A method for preparing a new energy lithium battery material, characterized in that, Includes the following steps: Step 1: Preheat lithium iron phosphate at 65~70℃ for 1 hour to obtain preheated lithium iron phosphate. Stir the preheated lithium iron phosphate and carbon nanotube modified liquid at a weight ratio of 3:(5~8) to obtain carbon nanotube modified lithium iron phosphate liquid. Step 2: The carbon nanotube-modified lithium iron phosphate solution and B-La dopant are ball-milled and adjusted at a weight ratio of (8~11):

5. After ball milling, the solution is filtered and dried to obtain the B-La-modified lithium iron phosphate body. Step 3: The B-La compounded lithium iron phosphate body and fiber reinforcing liquid are ball-milled at a weight ratio of (11~15):

7. After ball milling, the mixture is filtered and dried to obtain the new energy lithium battery material. The preparation method of carbon nanotube modified liquid is as follows: S01: Stir carbon nanotubes thoroughly in a sufficient amount of potassium permanganate solution with a mass fraction of 5-8%, then wash with water, filter, and dry. Preheat the dried carbon nanotubes at 135-145℃ for 1-1.5h, and then cool them to 60℃ at a rate of 2-5℃ / min. Keep them warm to obtain heat-insulated carbon nanotubes. SO2: 5-8 parts of heat-insulating carbon nanotubes, 6-10 parts of sodium dodecylbenzenesulfonate solution, 1-2 parts of silane coupling agent KH550 and 3-5 parts of alumina are thoroughly mixed to obtain carbon nanotube modified solution; The preparation method of the B-La dopant is as follows: S11, β-cyclodextrin, 75-85% ethanol aqueous solution and silane coupling agent KH560 are mixed evenly in a weight ratio of (3-5):7:(1-3) to obtain β-cyclodextrin solution; Nano-titanium dioxide was irradiated in a proton irradiation chamber for 1 hour at an irradiation power of 350-400W. After irradiation, irradiated nano-titanium dioxide was obtained. 4-7 parts of irradiated nano-titanium dioxide and 10-15 parts of β-cyclodextrin solution were mixed evenly to obtain nano-titanium dioxide-β-cyclodextrin complex solution. S12, Preparation of hybrid blending solution: S12a, nano-bismuth oxide, zirconium oxide and 10% sodium citrate solution are mixed evenly in a weight ratio of (3~5):(2~3):7 to obtain an impregnation solution; S12b involves immersing graphene in an impregnation solution that is 5 to 8 times the total amount of graphene. After impregnation, the solution is filtered and dried to obtain the impregnated graphene agent. S12c, the impregnated graphene agent and nano titanium dioxide-β-cyclodextrin complex solution are stirred at a weight ratio of (5~8):

13. After stirring, a hybrid mixture is obtained. S13, hybrid blending solution and B-La blending agent are ball-milled at a weight ratio of (11~14):5, ball milling speed is 1050~1150 r / min, ball milling for 2 h, after ball milling is completed, filter and dry to obtain B-La dopant; The preparation method of the B-La modifier is as follows: Mix 3-5 parts boron oxide, 2-4 parts lanthanum oxide and 7-11 parts sodium lignosulfonate solution evenly, then add 2-4 parts zinc oxide whiskers and 1-2 parts urea solution, mix thoroughly, and finally filter and dry to obtain B-La additive. The fiber reinforcing liquid is prepared by mixing 4-7 parts of carbon fiber, 3-5 parts of kaolin, 5-8 parts of sodium silicate solution with a mass fraction of 4-7% and 1-2 parts of sodium carboxymethyl cellulose thoroughly to obtain the fiber reinforcing liquid.

2. The method for preparing a new energy lithium battery material according to claim 1, characterized in that, The stirring speed for the stirring process is 550~650 r / min, and the stirring time is 2 h. The ball milling speed for the first adjustment treatment was 750~850 r / min, and the ball milling time was 2 hours; the ball milling speed for the second adjustment treatment was 1150~1250 r / min, and the ball milling time was 1 hour.

3. The method for preparing a new energy lithium battery material according to claim 1, characterized in that, The sodium dodecylbenzenesulfonate solution has a mass fraction of 10-15%.

4. The method for preparing a new energy lithium battery material according to claim 1, characterized in that, The impregnation treatment uses an ultrasonic power of 550~600W and is performed for 1 hour; the stirring speed in S12c is 350~400r / min and the stirring is performed for 35~45min.

5. The method for preparing a new energy lithium battery material according to claim 1, characterized in that, The urea solution has a mass fraction of 2-5%; the sodium lignosulfonate solution has a mass fraction of 5-8%.

6. The new energy lithium battery material prepared by the preparation method of the new energy lithium battery material according to any one of claims 1 to 5.

Images