Method for preparing spherical nickel oxide negative electrode material from different nickel sources and application of spherical nickel oxide negative electrode material
By using NiCl2 and NiSO4.6H2O as nickel sources, NiO materials with different morphology and particle sizes are prepared, which solves the volume expansion and lithium dendrites of the negative electrode materials of existing lithium-ion batteries, and achieves the improvement of high specific capacity and stable circulation performance. It is suitable for lithium-ion batteries and ternary lithium batteries.
Patent Information
- Application Number
- CN202510606558.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-05-12
- Publication Date
- 2025-08-08
AI Technical Summary
Existing lithium-ion battery anode materials such as graphite and hard carbon have challenges in volume expansion and lithium dendrites growth, resulting in insufficient performance, and new anode materials need to be developed to improve battery energy density and cycling performance.
NiCl2 and NiSO4.6H2O as nickel sources were used to prepare NiO materials with different surface micromorphology and particle sizes by sintering, including stirring, centrifugation, washing, drying and sintering steps, and the stoichiometric ratio of the nickel source to urea was regulated to optimize the electrochemical performance.
The prepared NiO negative electrode material exhibits high specific capacity and stable cycling performance, has a higher initial discharge capacity than commercial NiO materials, and has a long cycle life, which is suitable for lithium-ion batteries and ternary lithium battery materials.
Smart Images
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Abstract
Description
Technical Field
[0001] The present invention relates to the technical field of lithium ion battery negative electrode material preparation, in particular to a method for preparing a negative electrode material by using NiCl2 and NiSO4 . 6H2O was used as a different nickel source to prepare NiO negative electrode materials. The prepared NiO negative electrode materials have different surface micromorphologies and different particle sizes. When used as negative electrode materials for lithium-ion batteries, they have higher specific capacity and better cycle performance. Background Art
[0002] With the global emphasis on environmental protection and energy transition, new energy materials are playing an increasingly important role in today's society. In the context of carbon neutrality, traditional fossil fuels are unable to meet the needs of sustainable development. To alleviate the energy crisis, lithium-ion batteries, due to their high efficiency, environmental friendliness, and reusability, are gaining increasing favor among researchers. They are currently widely used in electric vehicles, small portable electronic devices, and energy storage devices.
[0003] Anode materials are an essential component of lithium-ion batteries. Their primary function is to store lithium ions and insert and extract them during the charge and discharge process, completing the battery's charge and discharge cycle. Common anode materials include graphite, hard carbon, and silicon-based materials. While these have high theoretical specific capacities and can effectively increase the energy density of lithium-ion batteries, they face challenges such as volume expansion and lithium dendrite growth. Therefore, the development of new anode materials is essential. Summary of the Invention
[0004] Based on the above shortcomings of the prior art, the present invention provides a method for . A method for preparing NiO materials with different morphologies using 6H2O as a different nickel source was developed and applied to the field of lithium-ion battery negative electrodes.
[0005] In order to solve the above-mentioned deficiencies and achieve the purpose of optimizing negative electrode materials, the present invention proposes the following technical solutions:
[0006] One of the technical solutions of the present invention:
[0007] S1, NiCl2 or NiSO4 . 6H2O, urea is weighed according to the stoichiometric ratio and poured into deionized water;
[0008] S2. Place the beaker containing deionized water on a magnetic stirrer and stir to form a uniform mixed solution;
[0009] S3. Place the mixed solution in a constant temperature box to react for a certain period of time.
[0010] S4. Centrifuge and wash the mixed solution after the reaction.
[0011] S5. Dry the washed sample.
[0012] S6. Sintering the dried sample.
[0013] In the S1, the stoichiometric ratio of the nickel source to the urea is 1:x (x=1-5).
[0014] In the S2, the amount of deionized water is 200-300 mL, and the stirring time is 30-60 minutes.
[0015] In S3, the temperature of the thermostat is 80-100° C., and the reaction time is 36-48 hours.
[0016] In the above S4, the washing conditions are washing with deionized water for 3-5 times and washing with anhydrous ethanol for 3-5 times.
[0017] In the step S5, the drying conditions are vacuum drying, the vacuum degree is -0.08 MPa, the temperature is 80-100° C., and the drying time is 6-8 hours.
[0018] In the step S6, the sintering temperature is 300-350° C., and the sintering time is 5-8 hours.
[0019] Compared with the prior art, the present invention has the following advantages and technical effects:
[0020] (1) The method of the present invention is simple, the conditions are easy to control, and it is easier to promote production. The prepared NiO electrode has a high specific capacity. The NiO negative electrode material prepared using NiCl2 as the nickel source exhibits a capacity of 311 mAhg at 1C and 25°C. -1 Initial discharge capacity using NiSO4 . The NiO anode material prepared with 6H2O as nickel source showed a high capacity of 280.7 mAh g -1 The initial discharge capacity is higher than that of commercial NiO negative electrode materials (266.3 mAh g -1 ).
[0021] (2) By using different nickel sources and regulating the stoichiometric ratio of nickel source to urea, the surface morphology of NiO can be changed, thereby effectively improving the electrochemical performance of NiO. DETAILED DESCRIPTION
[0022] Various exemplary embodiments of the present invention are now described in detail. This detailed description should not be considered as a limitation of the present invention, but should be understood as a more detailed description of certain aspects, characteristics and embodiments of the present invention. It should be understood that the terms described in the present invention are only for describing particular embodiments and are not intended to limit the present invention. In addition, for the numerical ranges in the present invention, it should be understood that each intermediate value between the upper and lower limits of the range is also specifically disclosed. Each smaller range between the intermediate value within any stated value or stated range and any other stated value or intermediate value within the range is also included in the present invention. The upper and lower limits of these smaller ranges may be independently included or excluded within the scope.
[0023] The characteristics and performance of the present invention are further described in detail below with reference to the embodiments.
[0024] Example 1:
[0025] 0.48 mmol NiSO4.6H2O was added to 200 mL deionized water, followed by 0.96 mmol urea, and the mixture was stirred for 40 minutes. The mixture was placed in a thermostat at 90°C for 48 hours to complete the reaction. The mixture was centrifuged and washed three times with deionized water and then three times with anhydrous ethanol. The mixture was then vacuum dried at 80°C for 6 hours and calcined at 300°C in a tube furnace for 5 hours. After sintering, the sample was naturally cooled to room temperature, taken out, and ground into powder using a mortar to obtain NiO powder.
[0026] The specific synthetic route is: BRIEF DESCRIPTION OF THE DRAWINGS
[0027] In order to more clearly illustrate the technical solutions of the trial examples of the present invention, the following is a brief introduction to the drawings required for use in the embodiments. The following drawings only illustrate certain specific embodiments of the present invention and should not be considered as limiting the present invention:
[0028] Figure 1 2 is the XRD pattern of the embodiment. Taking the NiO material obtained in this embodiment as an example, it was used as the negative electrode material of the lithium ion battery. The phase composition was identified using an X-ray diffractometer (model: Rigaku miniFlex600, scan rate: 5° / min). The diffraction peak position appearing in Example 1 corresponds to NiO (PDF#44-1159). These results indicate that the NiO synthesized by this method is pure phase and has good crystallinity.
[0029] The specific application of the NiO material prepared in this embodiment as a negative electrode material for lithium-ion batteries is as follows:
[0030] The preparation process of the negative electrode sheet uses the NiO material in Example 1 as the active material, SuperP as the conductive agent, and polyvinylidene fluoride (PVDF) dissolved in N-methylpyrrolidone as a binder. Then, the active material NiO material, SuperP, and PVDF are weighed according to a mass ratio of 8:1:1. The active material and SuperP are weighed and mixed according to the proportion and ground evenly, then poured into a mixing box, and then a certain amount of N-methylpyrrolidone is added. The mixing box is placed in a mixer, first mixed at a speed of 800r / min for 5 minutes, and then mixed at a speed of 2000r / min for 15 minutes. Finally, the resulting slurry is applied to a clean copper foil using a coating machine with a coating thickness of 200um. The coated electrode sheet is placed in a vacuum oven at 60-120℃ and dried for 8-12h, then taken out and cut into electrode sheets with a diameter of 12mm for standby use. A button-type lithium-ion battery is assembled using a 1M lithium hexafluorophosphate (LiPF6) solution dissolved in a 1:1:1 volume ratio of diethyl carbonate (DEC), dimethyl carbonate (DMC), and ethylene carbonate (EC) as the electrolyte. A lithium sheet serves as the counter electrode, a Celgard 2320 microporous polypropylene membrane serves as the separator, and a CR2025 stainless steel battery case. The assembled half-cell is then clamped on a Blue Electric test system for testing. The remaining steps in the lithium-ion battery production process are identical to conventional production methods.
[0031] Figure 2 NiCl2 and NiSO4 . SEM images of NiO materials synthesized with 6H2O as nickel source. The NiO synthesized with NiCl2 as nickel source has a smaller particle size of about 2um and is spherical. . NiO synthesized with 6H2O as nickel source has a larger particle size of about 10 μm and presents a flower-like microsphere morphology.
[0032] Figure 3 The discharge performance cycle diagrams for the examples and comparative examples show that the prepared NiO material, when used as a negative electrode material for lithium-ion batteries, exhibits good cycling performance and a long cycle life, remaining stable after 500 charge-discharge cycles. In the first 300 charge-discharge cycles, the discharge specific capacity of Example 1 is significantly superior to that of Comparative Example 1.
[0033] Example 2:
[0034] The difference between Example 2 and Example 1 is that the NiO negative electrode material used in Example 2 is prepared using NiCl2 as a nickel source, and other preparation conditions and parameter settings are exactly the same as those in Example 1.
[0035] Comparative Example 1:
[0036] The difference between Comparative Example 1 and Example 1 is that the negative electrode active material used in Comparative Example 1 is commercial NiO material, and other preparation conditions and parameter settings are exactly the same as those in Example 1.
[0037] Result analysis:
[0038] Discharge conditions <![CDATA[Initial discharge capacity (mAh g -1 )]]> Example 1 1C 280.7 Example 2 1C 311 Comparative Example 1 1C 266.3
[0039] The NiO negative electrode material prepared by the present invention has a higher discharge capacity and effectively improves its initial discharge capacity.
[0040] The above description is only a preferred embodiment of the present invention and should not be used to limit the scope of rights of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and changes can be made without departing from the principles of the present invention. These improvements and changes are also considered to be within the scope of protection of the present invention.
Claims
1. A method for preparing a nickel oxide negative electrode material using different nickel sources comprises the following steps: S1, NiCl2 or NiSO4 . 6H2O, urea is weighed according to the stoichiometric ratio and poured into deionized water; S2. Place the beaker containing deionized water on a magnetic stirrer and stir to form a uniform mixed solution; S3. Place the mixed solution in a constant temperature box to react for a certain period of time. S4. Centrifuge and wash the mixed solution after the reaction. S5. Dry the washed sample. S6. Sintering the dried sample.
2. Preparation of nickel oxide negative electrode material using different nickel sources according to claim 1, characterized in that: In step S1 , the stoichiometric ratio of the nickel source to the urea is 1:x (x=1-5).
3. The method of preparing nickel oxide negative electrode material from different nickel sources according to claim 1, wherein: In step S2, the amount of deionized water is 200-300 mL, and the stirring time is 30-60 minutes.
4. The method of preparing nickel oxide negative electrode material from different nickel sources according to claim 1, wherein: In step S3, the temperature of the constant temperature box is 80-100° C., and the reaction time is 36-48 hours.
5. Preparation of nickel oxide negative electrode material using different nickel sources according to claim 1, characterized in that: In step S4, the washing conditions are washing with deionized water for 3-5 times and washing with anhydrous ethanol for 3-5 times.
6. Preparation of nickel oxide negative electrode material using different nickel sources according to claim 1, characterized in that: In step S5, the drying conditions are vacuum drying, the vacuum degree is -0.08 MPa, the temperature is 80-100° C., and the drying time is 6-8 hours.
7. Preparation of nickel oxide negative electrode material using different nickel sources according to claim 1, characterized in that: In step S6, the sintering temperature is 300-350° C., and the sintering time is 5-8 hours.
8. Preparation of nickel oxide negative electrode material using different nickel sources according to claim 1, characterized in that: NiCl2 and NiSO4 were used as nickel sources respectively. . When 6H2O is used as the nickel source, the obtained NiO has different morphologies.
9. Preparation of nickel oxide negative electrode material using different nickel sources according to claim 1, characterized in that: NiCl2 and NiSO4 were used as nickel sources respectively. . When 6H2O is used as the nickel source, the obtained NiO has different particle sizes.