Preparation method and application of glycerol intercalation nickel hydroxide electrode material
By introducing glycerol between the nickel hydroxide layers, a glycerol intercalated nickel hydroxide electrode material was prepared, which solved the problems of poor circulation performance and poor rate performance of the nickel hydroxide electrode material, and achieved high lithium storage performance in lithium-ion batteries.
Patent Information
- Application Number
- CN202411917987.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-24
- Publication Date
- 2025-04-15
AI Technical Summary
As the negative electrode material of lithium-ion batteries, nickel hydroxide has problems such as poor circulation performance, poor rate performance, and slow electrochemical reaction kinetics, which hinders its practical application in lithium-ion batteries.
By introducing glycerol between the layers of nickel hydroxide, a glycerol intercalated nickel hydroxide electrode material was prepared. The hydroxyl group of glycerol is used to facilitate the rapid transmission of Li+, widen the layer spacing of nickel hydroxide, and improve its electrochemical performance.
Glycerol intercalated nickel hydroxide electrode material exhibits excellent cycling and rate performance in lithium-ion batteries, significantly improving the lithium storage performance of nickel hydroxide electrode material.
Smart Images
Figure CN119833598A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to the technical field of negative electrode materials for lithium ion batteries, and in particular to a preparation method and application of a high-performance glycerol intercalated nickel hydroxide electrode material. Background Art
[0002] With the in-depth implementation of the national "dual carbon" strategy and the rapid development of the electric vehicle industry, the development of a new generation of lithium-ion batteries with high energy density, high power density and good safety has become a research hotspot in the field of electrochemical energy. The electrochemical properties of electrode materials are the key factors that determine the overall performance of lithium-ion batteries. However, the carbon-based negative electrode materials widely used in business have problems such as low theoretical capacity (372 mAh / g) and poor safety, which are not conducive to the further improvement of the performance of lithium-ion batteries. Among the many new negative electrode materials, nickel hydroxide (Ni(OH)2) has the advantages of high theoretical specific capacity (~1700 mAh / g), relatively low cost, easy preparation, and good safety. It is considered to be a new type of lithium-ion battery negative electrode material with great application prospects. However, nickel hydroxide as a negative electrode material for lithium-ion batteries has problems such as poor cycle performance, poor rate performance, and slow electrochemical reaction kinetics, which seriously hinder the practical application of this material. In order to solve these problems, the most commonly used methods are to prepare nickel hydroxide with specific nano-morphology, dope and modify the nickel hydroxide layer, and composite nickel hydroxide with conductive carbon materials. These methods have improved the lithium storage performance of nickel hydroxide to a certain extent. As a typical layered compound, nickel hydroxide has good controllability between layers. By widening the interlayer spacing and introducing molecules with specific functions between the layers, it is expected to further improve the lithium storage performance of the material. However, no research on this aspect has been reported so far. Propylene glycol is a simple polyol compound that is non-toxic and environmentally friendly. Its molecular size is moderate and the hydroxyl groups on the molecular chain are conducive to Li + Based on the above considerations, the present invention proposes a method for preparing a glycerol intercalated nickel hydroxide electrode material, and using it as a negative electrode material for lithium ion batteries exhibits excellent electrochemical properties. Summary of the invention
[0003] The purpose of the present invention is to provide a preparation method of a glycerol intercalated nickel hydroxide electrode material and its application.
[0004] The specific steps for preparing the glycerol intercalated nickel hydroxide electrode material are as follows:
[0005] (1) Mix 5 mmol of nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O) and 0-15 mL of propylene glycol (C3H8O3). Add deionized water to dissolve the mixture and make up to 55 mL with deionized water.
[0006] (2) Under an argon atmosphere, 10 mL of 1 mol / L NaOH solution was dropwise added to the solution obtained in step (1), and the mixture was stirred at 60°C for 1 hour. The mixture was then transferred to a stainless steel autoclave and reacted at 120°C for 12 hours. The mixture was naturally cooled to room temperature and centrifuged. The resulting precipitate was freeze-dried to a constant weight to obtain a glycerol intercalated nickel hydroxide electrode material.
[0007] The glycerol intercalated nickel hydroxide electrode material of the present invention is applied to negative electrode materials of lithium ion batteries.
[0008] The glycerol intercalated nickel hydroxide electrode material prepared by the method of the present invention has significantly improved performance as a negative electrode material for lithium ion batteries compared with the performance of the nickel hydroxide electrode material without glycerol intercalation, thereby providing a new method for improving the lithium storage performance of the nickel hydroxide electrode material. In addition, the method of the present invention is simple and the operating parameters are easy to control. BRIEF DESCRIPTION OF THE DRAWINGS
[0009] Figure 1 XRD patterns of the nickel hydroxide electrode material prepared in Example 1 of the present invention and the glycerol intercalated nickel hydroxide electrode materials prepared in Examples 2 to 4.
[0010] Figure 2 FT-IR graphs of the nickel hydroxide electrode material prepared in Example 1 of the present invention and the glycerol intercalated nickel hydroxide electrode material prepared in Example 4.
[0011] Figure 3 This is a FESEM image of the nickel hydroxide electrode material prepared in Example 1 of the present invention.
[0012] Figure 4 This is a FESEM image of the glycerol intercalated nickel hydroxide electrode material prepared in Example 2 of the present invention.
[0013] Figure 5 This is a FESEM image of the glycerol intercalated nickel hydroxide electrode material prepared in Example 3 of the present invention.
[0014] Figure 6 This is a FESEM image of the glycerol intercalated nickel hydroxide electrode material prepared in Example 4 of the present invention.
[0015] Figure 7 The cycle performance curves of the nickel hydroxide electrode material prepared in Example 1 of the present invention and the glycerol intercalated nickel hydroxide electrode material prepared in Examples 2 to 4.
[0016] Figure 8 The rate performance curves of the nickel hydroxide electrode material prepared in Example 1 of the present invention and the glycerol intercalated nickel hydroxide electrode materials prepared in Examples 2 to 4. DETAILED DESCRIPTION
[0017] The present invention is further described below in conjunction with specific embodiments. It should be pointed out that the following embodiments are for those skilled in the art to better understand the present invention, rather than limiting the scope of protection of the present invention. Those skilled in the art can make some non-essential improvements and adjustments based on the above content.
[0018] Embodiment 1:
[0019] (1) Weigh 5 mmol of nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O), dissolve it in deionized water, and make up to 55 mL with deionized water.
[0020] (2) Under an argon atmosphere, 10 mL of 1 mol / L NaOH solution was added dropwise to the solution obtained in step (1), and the mixture was stirred at 60°C for 1 hour. The mixture was then transferred to a stainless steel autoclave and reacted at 120°C for 12 hours. The mixture was naturally cooled to room temperature and centrifuged. The resulting precipitate was freeze-dried to a constant weight to obtain a nickel hydroxide electrode material.
[0021] Embodiment 2:
[0022] (1) Mix 5 mmol of nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O) and 5 mL of propylene glycol (C3H8O3). Then add deionized water to dissolve the mixture and make up to 55 mL with deionized water.
[0023] (2) Under an argon atmosphere, 10 mL of 1 mol / L NaOH solution was dropwise added to the solution obtained in step (1), and the mixture was stirred at 60°C for 1 hour. The mixture was then transferred to a stainless steel autoclave and reacted at 120°C for 12 hours. The mixture was naturally cooled to room temperature and centrifuged. The resulting precipitate was freeze-dried to a constant weight to obtain a glycerol intercalated nickel hydroxide electrode material.
[0024] Embodiment 3:
[0025] (1) Mix 5 mmol nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O) and 10 mL propylene glycol (C3H8O3). Add deionized water to dissolve the mixture and make up to 55 mL with deionized water.
[0026] (2) Under an argon atmosphere, 10 mL of 1 mol / L NaOH solution was dropwise added to the solution obtained in step (1), and the mixture was stirred at 60°C for 1 hour. The mixture was then transferred to a stainless steel autoclave and reacted at 120°C for 12 hours. The mixture was naturally cooled to room temperature and centrifuged. The resulting precipitate was freeze-dried to a constant weight to obtain a glycerol intercalated nickel hydroxide electrode material.
[0027] Embodiment 4:
[0028] (1) Mix 5 mmol nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O) and 15 mL propylene glycol (C3H8O3). Add deionized water to dissolve the mixture and make up to 55 mL with deionized water.
[0029] (2) Under an argon atmosphere, 10 mL of 1 mol / L NaOH solution was dropwise added to the solution obtained in step (1), and the mixture was stirred at 60°C for 1 hour. The mixture was then transferred to a stainless steel autoclave and reacted at 120°C for 12 hours. The mixture was naturally cooled to room temperature and centrifuged. The resulting precipitate was freeze-dried to a constant weight to obtain a glycerol intercalated nickel hydroxide electrode material.
[0030] Application example: The electrode materials prepared in the above-mentioned embodiments 1 to 4 are respectively used as active materials, conductive carbon black (SuperP) is used as a conductive agent, and polyvinylidene fluoride (PVDF) is used as a binder, and the mixture is mixed in a mass ratio of 6:3:1. Then, the mixture is ground evenly, and an appropriate amount of N-methyl-2-pyrrolidone (NMP) is added as a solvent to mix into a slurry, and then the mixture is evenly coated on a copper foil, and vacuum dried at 80 ° C for 12 hours. After punching, a circular electrode sheet with a diameter of 16 mm is obtained. The circular electrode sheet obtained after punching is used as a working electrode, a metal lithium sheet is used as a counter electrode, a polypropylene porous membrane (Celgard 2500) is used as a diaphragm, and a mixed solution of ethylene carbonate (EC), dimethyl carbonate (DMC) and diethyl carbonate (DEC) (v(EC):v(DMC):v(DEC)=1:1:1) of 1 mol / LLiPF6 is used as an electrolyte, and a CR2016 button half-cell is assembled in a glove box filled with argon. The button half-cell was tested for constant current charge and discharge using the Neware BTS-5V / 10 mA battery test system. The potential window for the cycle performance test was 0.01~3.0 V (vs. Li / Li + ), first activated at a current density of 0.2 A / g for 5 cycles, and then charged and discharged for 500 cycles at a current density of 0.5 A / g. The potential window for rate performance test is 0.01~3.0 V (vs. Li / Li +), the test was conducted in two consecutive stages: the first stage was conducted at current densities of 0.2 A / g, 0.5 A / g, 1 A / g, 2 A / g, 3 A / g and 5 A / g for 5 cycles respectively; the second stage was conducted at a current density of 0.5 A / g for 10 cycles. The cycle performance test results of the electrode materials prepared in Examples 1 to 4 are listed in Table 1, and the rate performance test results are listed in Table 2.
[0031] Table 1 Cyclic performance test results of electrode materials prepared in Examples 1 to 4 (6 to 500 cycles)
[0032]
[0033] Table 2 Rate performance test results of electrode materials prepared in Examples 1 to 4
[0034]
[0035] As shown in Tables 1 and 2, the cycle performance and rate performance of the propylene glycol intercalated nickel hydroxide electrode materials prepared in Examples 3 and 4 are significantly better than those of the nickel hydroxide electrode material prepared in Example 1, especially the propylene glycol intercalated nickel hydroxide electrode material prepared in Example 4 has the best cycle performance and rate performance.
[0036] from Figure 1 It can be seen that the physical phase of the electrode material prepared in Example 1 is β-phase nickel hydroxide, the physical phase of the electrode material prepared in Example 2 is α / β mixed phase nickel hydroxide, the physical phase of the electrode materials prepared in Examples 3 and 4 are both α-phase nickel hydroxide, and the interlayer spacing of the nickel hydroxide prepared in Examples 2 to 4 is significantly widened, indicating that propylene glycol enters the nickel hydroxide interlayer, and therefore the nickel hydroxide prepared in Examples 2 to 4 is propylene glycol intercalated nickel hydroxide.
[0037] from Figure 2 It can be seen that the electrode material prepared in Example 3 contains the infrared vibration peak of glycerol, which further indicates that glycerol enters the nickel hydroxide interlayer and the prepared material is glycerol intercalated nickel hydroxide.
[0038] from Figure 3 It can be seen that the electrode material prepared in Example 1 is composed of nano disc-shaped particles (with a diameter of about 100 nm).
[0039] from Figure 4 It can be seen that the electrode material prepared in Example 2 is composed of nano-sheet particles (thickness is about 20 nm).
[0040] from Figure 5 It can be seen that the electrode material prepared in Example 3 is composed of wrinkled agglomerates.
[0041] from Figure 6It can be seen that the electrode material prepared in Example 4 has a porous structure (pore size is 200-500 nm).
[0042] from Figure 7 and Figure 8 It can be seen that the propylene glycol intercalation nickel hydroxide electrode material prepared by the method of the present invention has excellent lithium storage performance. It can also be found that propylene glycol intercalation is an effective method to improve the lithium storage performance of nickel hydroxide electrode materials.
Claims
1. A method for preparing a glycerol intercalated nickel hydroxide electrode material, characterized in that: The specific steps are: (1) Mix 5 mmol of nickel acetate tetrahydrate (Ni(CH3COO)2·4H2O) and 0-15 mL of propylene glycol (C3H8O3), then add deionized water to dissolve the mixture and make up to 55 mL with deionized water; (2) Under an argon atmosphere, 10 mL of 1 mol / L NaOH solution was dropwise added to the solution obtained in step (1), and the mixture was stirred at 60°C for 1 hour. The mixture was then transferred to a stainless steel autoclave and reacted at 120°C for 12 hours. The mixture was naturally cooled to room temperature and centrifuged. The resulting precipitate was freeze-dried to a constant weight to obtain a glycerol intercalated nickel hydroxide electrode material.
2. An application of the glycerol intercalated nickel hydroxide electrode material prepared by the method according to claim 1, characterized in that The glycerol intercalated nickel hydroxide electrode material is applied to negative electrode materials of lithium ion batteries.