POWER-TYPE NICKEL COBALT LITHIUM MANGANESE OXIDE MATERIAL, AND PREPARATION METHOD THEREFOR AND USES THEREOF

Abstract

The present invention relates to the technical field of preparation of a nickel cobalt lithium manganese oxide positive electrode material. Disclosed are a power-type nickel cobalt lithium manganese oxide material and a preparation method therefor and uses thereof. The preparation method comprises: adding an organic acid into a mixed aqueous solution of a lithium source, a nickel source, a cobalt source and a manganese source, aging, obtaining a sol precursor, obtaining a gel fiber through electrospinning, and obtaining the power-type nickel cobalt lithium manganese oxide material after calcination. In the present invention, the nickel cobalt lithium manganese oxide material of a nano-fiber structure is prepared by using a sol-gel electrospinning method, and the nickel cobalt lithium manganese oxide material of a nano-fiber structure has a uniform structure size, thereby effectively reducing surface energy, and improving a capacity of lithium ions.

Claims

1. A method for preparing power-type nickel cobalt lithium manganese oxide material, comprising: adding organic acid into a mixed aqueous solution of a lithium source, a nickel source, cobalt source, and a manganese source; aging, to obtain a sol precursor; electrospinning, to obtain a gel fiber; and calcinating to obtain the power-type nickel cobalt lithium manganese oxide material.

2. The method according to claim 1, wherein in the mixed aqueous solution, a concentration of the nickel source is 13 mol/L, wherein a concentration of the cobalt source is 13 mol/L, wherein a concentration of the manganese source is 13 mol/L, wherein a concentration of the lithium source is 12 times of a total concentration of the nickel source, the cobalt source, and the manganese source.

3. The method according to claim 1, wherein an amount of the organic acid is that a concentration of the organic acid in a system is 35 mol/L after adding the organic acid.

4. The method according to claim 1, wherein the organic acid is at least one of citric acid, tartaric acid, and oxalic acid.

5. The method according to claim 1, wherein the lithium source is at least one of lithium acetate, lithium hydrate, and lithium carbonate; wherein the nickel source is at least one of nickel acetate, nickel hydroxide, and nickel carbonate; wherein the cobalt source is at least one of cobalt acetate, cobalt hydroxide, and cobalt carbonate; and wherein the manganese source is at least one of manganese acetate, manganese hydroxide, and manganese carbonate.

6. The method according to claim 1, wherein the aging includes: heating to 6070 C. first; aging for 810 hours till transparent; and continuing aging at a room temperature till a viscosity is 23 Pa.Math.s.

7. The method according to claim 1, wherein process conditions of the electrospinning include: a nozzle aperture being 500 m, a feeding rate being 510 mL/h, a voltage being 2040 kV, a fixed distance between the nozzle and a collector being 1030 cm, and a pressure being 0.30.5 MPa.

8. The method according to claim 1, wherein process of the calcination includes: raising a temperature from the room temperature to 300400 C. at a rate of 0.51 C./min and holding for 13 hours; raising the temperature to 600800 C. at a rate of 24 C./min and holding for 810 hours.

9. A power-type nickel cobalt lithium manganese oxide material, wherein the power-type nickel cobalt lithium manganese oxide material is obtained through the preparing method according to claim 1.

10. A use of the power-type nickel cobalt lithium manganese oxide material according to claim 9 in a battery.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] FIG. 1 is the SEM (scanning electron microscope) picture of nickel cobalt lithium manganese oxide material prepared through Embodiment 1.

[0028] FIG. 2 is the curve graph of the capacity of charging and discharging of the nickel cobalt lithium manganese oxide material of Embodiment 1 and that of the comparing example.

DETAILED DESCRIPTION

[0029] Hereinafter, the present invention is further described in detail in accompany with embodiments and Figures. However, embodiments of the present invention are not limited hereto.

Embodiment 1

The Preparation of the Power-Type Nickel Cobalt Lithium Manganese Oxide Material

[0030] (1) 100 mL of mixed aqueous solution is prepared, wherein the concentrations are lithium acetate 3 mol/L, nickel acetate 1 mol/L, cobalt acetate 1 mol/L, manganese acetate 1 mol/L. The citric acid is added into the system, such that the concentration of sodium citrate is 3 mol/L. It is aged at 60 C. for 10 hours till it is sticky and transparent. It continues to be aged at the room temperature till the viscosity is 2 Pa.Math.s, so as to obtain the sol precursor.

[0031] (2) The sol is put into a syringe whose nozzle aperture is 500 m. The feeding rate is 5 mL/h. The voltage is 20 kV. The fixed distance between the nozzle and the collector is 10 cm. N.sub.2 is blown in till the pressure is 0.3 MPa. The spinning is conducted under the above conditions. Gel fibers are obtained. They are dried at 70 C. for 1 hour.

[0032] (3) Gel fibers obtained in step (2) are put into the calcinatory. In the atmosphere, the temperature is raised from the room temperature to 300 C. at a rate of 0.5 C./min and is held for 1 hour, and then is raised to 600 C. at a rate of 2 C./min and is held for 8 hours. The power-type nickel cobalt lithium manganese oxide material is obtained. The SEM is conducted, and the results are shown in FIG. 1. As shown in FIG. 1, the power-type nickel cobalt lithium manganese oxide material the present invention has uniform nanofiber structure.

Embodiment 2

The Preparation of the Power-Type Nickel Cobalt Lithium Manganese Oxide Material

[0033] (1) 100 mL of mixed aqueous solution is prepared, wherein the concentrations are lithium hydrate 9 mol/L, nickel hydroxide 2 mol/L, cobalt hydroxide 2 mol/L, manganese hydroxide 2 mol/L. Tartaric acid is added into the system, such that the concentration of tartaric acid is 4 mol/L. It is aged at 65 C. for 9 hours till it is sticky and transparent. It continues to be aged at the room temperature till the viscosity is 2 Pa.Math.s, so as to obtain the sol precursor.

[0034] (2) The sol is put into a syringe whose nozzle aperture is 500 m. The feeding rate is 7.5 mL/h. The voltage is 30 kV. The fixed distance between the nozzle and the collector is 20 cm. N.sub.2 is blown in till the pressure is 0.4 MPa. The spinning is conducted under the above conditions. Gel fibers are obtained. They are dried at 70 C. for 1 hour.

[0035] (3) Gel fibers obtained in step (2) are put into the calcinatory. In the atmosphere, the temperature is raised from the room temperature to 350 C. at a rate of 1 C./min and is held for 2 hours, and then is raised to 700 C. at a rate of 3 C./min and is held for 9 hours. The power-type nickel cobalt lithium manganese oxide material is obtained.

Embodiment 3

The Preparation of the Power-Type Nickel Cobalt Lithium Manganese Oxide Material

[0036] (1) 100 mL of mixed aqueous solution is prepared, wherein the concentrations are lithium carbonate 18 mol/L, nickel carbonate 3 mol/L, cobalt carbonate 3 mol/L, manganese carbonate 3 mol/L. oxalic acid is added into the system, such that the concentration of organic acid is 5 mol/L. It is aged at 70 C. for 8 hours till it is sticky and transparent. It continues to be aged at the room temperature till the viscosity is 3 Pa.Math.s, so as to obtain the sol precursor.

[0037] (2) The sol is put into a syringe whose nozzle aperture is 500 m. The feeding rate is 10 mL/h. The voltage is 30 kV. The fixed distance between the nozzle and the collector is 30 cm. N.sub.2 is blown in till the pressure is 0.5 MPa. The spinning is conducted under the above conditions. Gel fibers are obtained. They are dried at 70 C. for 1 hour.

[0038] (3) Gel fibers obtained in step (2) are put into the calcinatory, in the atmosphere, the temperature is raised from the room temperature to 400 C. at a rate of 1 C./min and is held for 1 hour, and then is raised to 800 C. at a rate of 4 C./min and is held for 10 hours. The power-type nickel cobalt lithium manganese oxide material is obtained.

Comparing Example

[0039] (1) 100 mL of mixed aqueous solution is prepared, wherein the concentrations are lithium acetate 3 mol/L, nickel acetate 1 mol/L, cobalt acetate 1 mol/L, manganese acetate 1 mol/L. The citric acid is added into the system, such that the concentration of organic acid is 3 mol/L. It is aged at 70 C. till it is sticky and transparent. It continues to be aged at the room temperature till the viscosity is 2 Pa.Math.s, so as to obtain the sol precursor.

[0040] (2) The sol precursor obtained in step (1) is put into the calcinatory. In the atmosphere, the temperature is raised from the room temperature to 300 C. at a rate of 0.5 C./min and is held for 1 hour, and then is raised to 600 C. at a rate of 2 C./min and is held for 8 hours. The nickel cobalt lithium manganese oxide comparing material is obtained.

[0041] Testing Example

[0042] With the lithium metal as the negative electrode, with the nickel cobalt lithium manganese oxide material of Embodiment 1 and that of Comparing Example as the positive electrode, a battery is assembled. The discharging test is conducted at a rate of 1 C. 1 C refers to the discharge ratio is 1 C. Discharge ratio refers to the battery discharge current relative to the ratio of nominal capacity. Nominal capacity (mAh)/discharge time(h)=discharge ratio (C). In theory, it use just 1 h to discharge the current of battery with 1 C rate. Results are shown in FIG. 2. As shown in the results, at the rate of 1 C, the specific capacity the nickel cobalt lithium manganese oxide positive electrode material of the present invention, which is around 170 mAh/g, is higher than that of ordinary sol-gel method.

[0043] The above embodiments are preferred embodiments of the present invention. However, the implementation of the present invention is not limited to the above embodiments. Any other alternations, modifications, replacements, combinations, simplifications, which do not depart from the spirit and principle of the present invention, are all equivalent alternative methods, which fall within the scope of the present invention.