CN116130616A - Preparation method for high-performance multi-element oxide electrode material - Google Patents

Abstract

The invention provides a preparation method for a high-performance multi-element oxide material, and belongs to the technical field of preparation of lithium ion battery anode materials. The method comprises the following steps: in a mixer, the spheroidal LiNi with the weight ratio of 6:4-8:2 is mixed _x Co _y Al _z O ₂ (0.96 is larger than or equal to x is larger than or equal to 0.80,0.15 is larger than or equal to y is larger than or equal to 0.02,0.05 is larger than or equal to z is larger than or equal to 0.02) multi-element oxide material and single crystal LiNi _x Co _y Al _z O ₂ (0.96 is more than or equal to x is more than or equal to 0.80,0.15 is more than or equal to y is more than or equal to 0.02,0.05 is more than or equal to z is more than or equal to 0.02) and the prepared multi-element oxide is uniformly mixedThe compaction density of the electrode material can reach 3.80g/cm ³ The specific capacity of the first discharge can reach more than 210 mAh/g. The multi-element oxide electrode material prepared by the invention not only has high compaction density, but also has higher specific discharge capacity, cycle performance and good high-temperature storage performance.

Description

A preparation method for high-performance multi-component oxide electrode materials

technical field

The invention belongs to the technical field of cathode materials for lithium ion batteries, and in particular relates to a preparation method for high-performance multi-element oxide electrode materials.

Background technique

With the rapid development of new energy vehicles, the performance of lithium-ion power batteries (such as energy density, rate performance, cycle life, safety performance, etc.) Develop in the direction of high capacity, light weight, rate performance, cycle performance and safety performance, especially in the direction of high energy density. For electrode materials, discharge specific capacity, working platform voltage, and compaction density are all key factors affecting the energy density of lithium-ion power batteries.

Multi-component oxide materials have the advantages of high capacity, excellent cycle and low price, and are currently the electrode materials with the largest share in the international market. With the continuous improvement of energy density requirements for lithium-ion power batteries, multi-component oxide materials continue to develop in the direction of high nickel content, high voltage, high compaction density and high safety. At present, multi-element oxide materials are basically spherical-like multi-element oxide materials with secondary spherical particles formed by agglomeration of primary particles, prepared from multi-element precursors synthesized by co-precipitation method. Compared with the compacted density (≥4.0g/cm ³ ) of single-crystal lithium cobalt oxide electrode materials, the compacted density of the existing spherical multi-component oxide materials is about 3.50g/cm ³ , and the compacted density Relatively low, resulting in low energy density of the lithium-ion power battery, so that the performance of the lithium-ion power battery cannot be maximized and realized.

Among the existing multiple oxide materials for lithium-ion power batteries, using a ternary material containing nickel, cobalt, and aluminum as the positive electrode material of the lithium-ion battery can make the lithium-ion battery have a better discharge specific capacity. In particular, as the content of nickel element increases, the discharge specific capacity of the lithium-ion power battery increases more significantly. At the same time, the monocrystalline multi-component oxide material has a regular appearance, which has a similar morphology and structure to the single-crystal lithium cobalt oxide electrode material. Compared with the multi-component oxide material with secondary spherical particles prepared by the coprecipitation method, it has High compaction density. The present invention prepares a high-performance electrode material by increasing the content of nickel element in the multi-element oxide material and grading the large-particle spherical multi-element oxide material and the single-crystal multi-element oxide material to increase the compaction density of the electrode material. The multi-element oxide electrode material can achieve a significant increase in the energy density of lithium-ion power batteries.

Contents of the invention

The purpose of the present invention is to provide a preparation method for high-performance multi-component oxide electrode materials.

In order to meet the above object, the technical scheme that the present invention takes is:

A preparation method for a high-performance multi-component oxide electrode material, characterized in that: using a mixer to mix spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥ 0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide materials and single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component The oxide materials are mixed for 2-10 hours to prepare high-performance multi-element oxide electrode materials.

Preferably, the particle size range of the spherical-like LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material satisfies 17μm≤D ₅₀ ≤19μm ; The particle size range of single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material satisfies 1.5μm≤D ₅₀ ≤3.5μm.

Preferably, the preparation method of the spherical-like LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material is as follows: first set D ₅₀ to 16 ~18μm quasi-spherical Ni _x Co _y Al _z (OH) ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component precursor material is pre-oxidized in the temperature range of 300～600℃ for 4～ After 10 hours, sieve to obtain Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) oxides with a D ₅₀ of 17-19 μm, and then Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) oxides and lithium salts were mixed for 2 to 8 hours, and the mixture was sintered at a temperature range of 400 to 600 °C for 6 to 10 hours, and then 300 Nylon sieve sieve treatment, sieve to get D ₅₀ is 17 ~ 19μm LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-element oxide material, and then Spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80，0.15≥y ≥0.02, 0.05≥z≥0.02) multi-component oxide materials.

Preferably, the molar ratio of the spherical Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.02≥y≥0.15, 0.02≥z≥0.05) multiple oxides and lithium salt is 1:1.00～1.15 .

Preferably, the preparation method of the single-crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multiple oxide material is as follows: firstly, D ₅₀ is 1.5-3.5μm single-crystal Ni _x Co _y Al _z (OH) ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) pre-oxidized in the temperature range of 300-500℃2 ~6h, sieve to obtain Ni _x Co _y Al _z O ₂ ( _{0.96≥x≥0.80} , 0.15≥y≥0.02, 0.05≥z≥0.02) oxides with D 50 of 1.5～3.5μm, and then set D ₅₀ to 1.5 ～3.5μm single crystal Ni _x Co _y Al _z O ₂ oxide and lithium salt are mixed for 2～8 hours, and the mixture is sintered at 350～550℃ for 4～8 hours, and then sieved with 400 mesh nylon sieve. Sieve to obtain LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide materials with D ₅₀ of 1.5～3.5μm, and then in the range of 750～900℃ After internal secondary sintering for 10 to 30 hours, cooling down, crushing, screening, removing metal foreign matter and other processes to prepare single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥ z≥0.02) multiple oxide materials.

Preferably, the molar ratio of the single-crystal Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide to lithium salt is 1:1.05～ 1.20.

Preferably, the lithium salt is one or both of lithium hydroxide and lithium oxide.

The beneficial effects of the present invention are:

A preparation method for a high-performance multi-component oxide material of the present invention, through the spherical-like LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) Multi-element oxide material and single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-element oxide material blending technology to obtain high compacted density, A high-performance multi-component oxide electrode material with advantages of high voltage and high capacity. The method has simple process, convenient operation, easy realization of industrialized production, and the production process is pollution-free and environment-friendly.

Instructions attached

The present invention will be described in further detail below in conjunction with the accompanying drawings.

Figure 1 shows the spherical-like LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multiple oxide materials (a) and single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) process flow chart for the preparation of multi-component oxide materials;

Figure 2 shows the spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material (a) and single crystal LiNi _x Co _y in Example 1 Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material (b) SEM image;

Figure 3 shows the spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material (a) and single crystal LiNi _x Co _y in Example 2 Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material (b) SEM image;

4 is a schematic diagram of the first discharge specific capacity of the multi-component oxide electrode material in Example 2.

Detailed ways

In order to better understand the present invention, the content of the present invention is further clearly described below in conjunction with the examples, but the protection content of the present invention is not limited to the following examples. In the following description, numerous specific details are given in order to provide a more thorough understanding of the present invention. It will be apparent, however, to one skilled in the art that the present invention may be practiced without one or more of these details. In other examples, some technical features known in the art are not described in order to avoid confusion with the present invention.

Example 1

a. Preparation of spherical LiNi _0.94 Co _0.04 Al _0.02 O ₂ multi-component oxide material, the specific steps are:

(1) Pre-oxidize the spherical Ni _0.94 Co _0.04 Al _0.02 (OH) ₂ precursor with a D ₅₀ of 17.6 μm in a box-type atmosphere resistance furnace, sinter at 400°C for 5 hours, then cool naturally with the furnace, and sieve to obtain D ₅₀ 18.3 μm spherical Ni _0.94 Co _0.04 Al _0.02 O ₂ oxide;

(2) Add battery-grade LiOH and the oxide obtained in (1) into a high-speed mixer at a molar ratio of Li/M=1.08:1 and mix for 30 minutes;

(3) Put the mixed material in (2) into an oxygen-enriched atmosphere box-type resistance furnace for multi-stage sintering, first pre-sinter at 500°C for 8 hours, cool naturally with the furnace, and sieve through a 300-mesh nylon sieve; then sinter at 750°C Sinter for another 6 hours, then cool down to 600°C at a rate of -0.5°C/min, then cool naturally with the furnace, crush and sieve to obtain a spherical LiNi _0.94 Co _0.04 Al _0.02 O ₂ multi-element oxide material.

b. Preparation of single crystal LiNi _0.90 Co _0.08 Al _0.02 O ₂ multiple oxide material, the specific steps are:

(1) The single-crystal Ni _0.90 Co _0.08 Al _0.02 (OH) ₂ precursor with a D ₅₀ of 2.6 μm was pre-oxidized in a box-type atmosphere resistance furnace, sintered at 350 ° C for 5 h, and then cooled naturally with the furnace, and sieved to obtain D ₅₀ is 2.7 μm single crystal Ni _0.94 Co _0.04 Al _0.02 O ₂ oxide;

(2) Add battery-grade LiOH and D ₅₀ of 2.7 μm monocrystalline Ni _0.90 Co _0.08 Al _0.02 O ₂ oxide into a high-speed mixer at a molar ratio of Li/M=1.15:1 and mix for 15 minutes;

(3) Put the mixed material in (2) into an oxygen-enriched atmosphere box-type resistance furnace for multi-stage sintering, first pre-sinter at 520°C for 6 hours, cool naturally with the furnace, and sieve with a 400-mesh nylon sieve; then sinter at 800°C Sintered for 12 hours, then cooled naturally with the furnace, crushed and sieved to obtain a single crystal LiNi _0.90 Co _0.08 Al _0.02 O ₂ multi-element oxide material.

c. Mix the spherical LiNi _0.94 Co _0.04 Al _0.02 O ₂ multiple oxide material and the single crystal LiNi _0.90 Co _0.08 Al _0.02 O ₂ multiple oxide material in a mixer for 5 hours according to a mass ratio of 8:2 to prepare A homogeneously mixed multi-component oxide material is obtained.

The powder compacted density of the multi-component oxide material prepared in the examples can reach 3.81g/cm ³ , within the voltage range of 2.8-4.3V, and within the temperature range of 25±1°C, the specific capacity for the first discharge at 0.1C is 217.4mAh /g.

Example 2

a. Preparation of spherical LiNi _0.94 Co _0.04 Al _0.02 O ₂ multi-component oxide material, the specific steps are:

(1) Pre-oxidize the spherical Ni _0.94 Co _0.04 Al _0.02 (OH) ₂ precursor with a D ₅₀ of 16.9 μm in a box-type atmosphere resistance furnace, sinter at 450°C for 4 hours, then cool naturally with the furnace, and sieve to obtain D ₅₀ 17.7 μm Ni _0.94 Co _0.04 Al _0.02 O ₂ oxide;

(2) Add battery-grade LiOH and the oxide obtained in (1) into a high-speed mixer at a molar ratio of Li/M=1.12:1 and mix for 20 minutes;

(3) Put the mixed material in (2) into an oxygen-enriched atmosphere box-type resistance furnace for multi-stage sintering, first pre-sinter at 550°C for 7 hours, cool naturally with the furnace, and sieve with a 300-mesh nylon sieve; then sinter at 740°C Sinter for 8 hours, then cool down to 600°C at a rate of -0.3°C/min, then cool naturally with the furnace, crush and sieve to obtain a spherical LiNi _0.94 Co _0.04 Al _0.02 O ₂ multi-element oxide material.

b. Preparation of single crystal LiNi _0.83 Co _0.12 Al _0.05 O ₂ multiple oxide material, the specific steps are:

(1) The single-crystal Ni _0.83 Co _0.12 Al _0.05 (OH) ₂ precursor with a D ₅₀ of 3.2 μm was pre-oxidized in a box-type atmosphere resistance furnace, sintered at 400 ° C for 6 h, and then cooled naturally with the furnace, and sieved to obtain D ₅₀ is 3.3 μm single crystal Ni _0.83 Co _0.12 Al _0.05 O ₂ oxide;

(2) Add battery-grade LiOH and single crystal Ni _0.83 Co _0.12 Al _0.05 O ₂ oxide with a D ₅₀ of 3.3 μm in a high-speed mixer at a molar ratio of Li/M=1.18:1 and mix for 20 minutes;

(3) Put the mixed material in (2) into an oxygen-enriched atmosphere box-type resistance furnace for multi-stage sintering, first pre-sinter at 540°C for 6 hours, cool naturally with the furnace, and sieve with a 400-mesh nylon sieve; then sinter at 780°C Sintered for 16 hours, then cooled naturally with the furnace, crushed and sieved to obtain a single crystal LiNi _0.83 Co _0.12 Al _0.05 O ₂ multi-element oxide material.

c. Mix the spherical LiNi _0.94 Co _0.04 Al _0.02 O ₂ multi-component oxide material and the single crystal LiNi _0.83 Co _0.12 Al _0.05 O ₂ multi-component oxide material in the mixer according to the mass ratio of 6:4 for 6 hours to prepare A homogeneously mixed multi-component oxide material is obtained. .

The powder compacted density of the multi-component oxide material prepared in the example can reach 3.85g/cm ³ , within the voltage range of 2.8-4.3V, and within the temperature range of 25±1°C, the specific capacity for the first discharge at 0.1C is 210.3mAh /g.

The above is a preferred embodiment of the present invention, and any simple modifications, equivalent changes and modifications made to the above embodiments according to the technical essence of the present invention fall within the scope of protection of the present invention.

Claims (7)

1. A preparation method for high-performance multi-component oxide electrode material, characterized in that the spherical LiNi _x Co _y Al _z O ₂ (0.96≥x ≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multiple oxide materials and single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) The multi-component oxide materials are mixed for 2-10 hours to prepare high-performance multi-component oxide electrode materials. 2. The preparation method of high-performance multi-component oxide electrode material according to claim 1, characterized in that spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥ 0.02) The particle size range of the multi-component oxide material satisfies 17μm≤D ₅₀ ≤19μm; single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxidation The particle size range of the object material satisfies 1.5μm≤D ₅₀ ≤3.5μm. 3. The preparation method of the high-performance multi-component oxide electrode material according to claim 1 or 2, characterized in that the spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥ z≥0.02) The preparation method of the multi-component oxide material is as follows: _first , the spherical Ni _x Co _y Al _z (OH) ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z ≥0.02) the precursor was pre-oxidized in the temperature range of 300-600°C for 4-10 hours, and sieved to obtain Ni _x Co _y Al _z O ₂ with a D ₅₀ of 17-19 μm (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) oxide, and then mix Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) oxide and lithium salt for 2 to 8 hours, the mixture After primary sintering at 400-600°C for 6-10 hours, sieve with a ₃₀₀ -mesh nylon sieve to obtain LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥ y ≥ 0.02, 0.05 ≥ z ≥ 0.02) multi-component oxide materials, and then sintered for 3 to 20 hours in the range of 720 ~ 880 ℃, cooling down, crushing, sieving, removing metal foreign matter and other processes to prepare spherical LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-element oxide material. 4. The preparation method of the multi-component oxide electrode material according to claim 3, characterized in that the spherical Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.02≥y≥0.15, 0.02≥z≥0.05) The molar ratio of oxide and lithium salt is 1:1.00-1.15. 5. The preparation method of multi-component oxide electrode material according to claim 1 or 2, characterized in that single crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z ≥0.02) The preparation method of the multi-component oxide material is as follows: _first , single crystal Ni _x Co _y Al _z (OH) ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥ z≥0.02) the precursor was pre-oxidized in the temperature range of 300～500℃ for 2～6h, and _sieved to obtain Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥ 0.02, 0.05≥z≥0.02) oxide, and then mix single crystal Ni _x Co _y Al _z O ₂ oxide with D ₅₀ of 1.5～3.5μm and lithium salt for 2～8h, the mixture is in the range of 350～550℃ After one sintering for 4-8 hours, carry out sieving treatment with ₄₀₀ -mesh nylon sieve to obtain LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05 ≥z≥0.02) multi-element oxide materials, and then sintered for 10-30 hours in the range of 750-900°C for 10-30 hours, then cooling down, crushing, sieving, removing metal foreign matter and other processes to prepare single-crystal LiNi _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02) multi-component oxide material. 6. The preparation method of multi-component oxide electrode material according to claim 5, characterized in that single crystal Ni _x Co _y Al _z O ₂ (0.96≥x≥0.80, 0.15≥y≥0.02, 0.05≥z≥0.02 ) The molar ratio of the oxide to the lithium salt is 1:1.05-1.20. 7. The preparation method of multi-component oxide electrode material according to claim 3 or 5, characterized in that the lithium salt is one or both of lithium hydroxide and lithium oxide.

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