CN102040249A

CN102040249A - Method for preparing lithium manganate nanowire made of positive material of lithium ion battery

Info

Publication number: CN102040249A
Application number: CN 201010570523
Authority: CN
Inventors: 赵铭姝; 宋晓平; 汪飞; 翟玉春
Original assignee: Xian Jiaotong University
Current assignee: Xian Jiaotong University
Priority date: 2010-12-02
Filing date: 2010-12-02
Publication date: 2011-05-04

Abstract

The invention discloses a method for preparing a lithium manganate nanowire made of a positive material of a lithium ion battery. The method is as follows: after ultrasonic treatment of Mn3O4 and a NaOH solution, adopting a hydrothermal synthesis method to prepare a precursor nanowire LiNa0.44Mn2O4 of LiMn2O4, carrying out solid-phase sintering, and then obtaining the nanowire LiNa0.44Mn2O4 with the wire diameter from 50 nanometers to 250 nanometers. By utilizing the method, the nanowire LiMn2O4 different from the shape of the traditional lithium manganate is prepared; and the lithium manganate nanowire can be used as an electrode material of the lithium ion battery for power. On the basis of the hydrothermal synthesis method and a solid-phase segmentation method, and by assistance of ultrasonic treatment, the whole reaction process is simple, the generation of toxic substances or environmental pollutants can be avoided, and the method is environment-friendly and belongs to a preparation method of green chemistry. In addition, by utilizing the method, large-scale production can be realized, and the needed chemical reagent is low in cost and is easy to buy.

Description

The preparation method of lithium cell anode material lithium manganate nano wire

Technical field

The invention belongs to material preparation method, particularly a kind of method for preparing anode material for lithium-ion batteries lithium manganate having spinel structure nano wire.

Background technology

The crystalline structure of lithium manganate commonly used mainly contains two kinds: one is spinel type LiMn ₂O ₄, two is monocline and oblique side's allopatric polymorphism stratiform LiMnO ₂Preparation method about lithium manganate type anode material for lithium-ion batteries has had a lot of bibliographical informations, chemical coprecipitation, sol-gel method, latex desiccating method, ultrasonic wave sputtering method, high-temperature decomposition, the solid phase stepwise processs etc. of adopting more, the microcosmic surface pattern of synthetic lithium manganate is regular octahedron shape (particle) or sheet, is applicable to anode material for lithium-ion batteries.Combination water thermal synthesis method and solid sintering technology, can prepare the nano wire lithium manganate, the microcosmic surface pattern that is lithium manganate is a nanowire-type, and the electrochemical property test result shows that its multiplying power property is better than traditional lithium manganate having spinel structure, is applied to the power lithium ion battery material.

Summary of the invention

The object of the present invention is to provide a kind of method for preparing the nano wire lithium cell anode material lithium manganate, synthetic lithium manganate nano wire can be used the positive electrode material of power with lithium ion battery.Entire reaction course of the present invention is simple, no toxic substance or environmental pollution deposits yields, and environmental friendliness belongs to the preparation method of Green Chemistry, and present method can realize scale operation, and required chemical reagent cheapness is easily purchased.

Technical scheme of the present invention is achieved in that

At first, the preparation volumetric molar concentration is 2.5-10.0molL ^-1NaOH solution, press Na _0.44Mn ₂O ₄Stoichiometric ratio takes by weighing Mn ₃O ₄With Mn ₃O ₄Mix with NaOH solution, ultra-sonic dispersion 10-20 minute, place hydrothermal reaction kettle, be heated to 205-225 ℃, constant temperature 3-5 days; Product in the reactor is washed suction filtration repeatedly, after the vacuum drying at room temperature, make LiMn ₂O ₄Presoma nano wire LiNa _0.44Mn ₂O ₄

Secondly, be to take by weighing LiNa at 1: 0.88: 0.12 in molar ratio _0.44Mn ₂O ₄, LiNO ₃, LiClH ₂O puts into ball grinder with above-mentioned raw materials, the agate mill ball of packing into, and ball milling 2-4 hour, obtain mixed slurry, be placed in the porcelain boat, put into resistance wire horizontal pipe stove, with 1-5 ℃ of min ^-1Temperature rise rate be heated to 450-550 ℃, be incubated 1-5 hour, cool to room temperature then with the furnace, the black product that obtains is washed suction filtration repeatedly, vacuum drying at room temperature 2-4 hour;

At last, dried product is placed porcelain boat, put into resistance wire horizontal pipe stove, with 1-5 ℃ of min ^-1Temperature rise rate be heated to 750-850 ℃, be incubated 1-4 hour; Cool to room temperature then with the furnace, in agate mortar, grind and obtain LiMn ₂O ₄Nano wire.

The heating member of described resistance wire tube furnace is the Fe-Cr-Al resistance wire.

By preparation nano wire LiMn provided by the invention ₂O ₄Hydrothermal synthesis method and solid phase stepwise process combine, select proper raw material proportioning and rational ultrasonic processing technique for use, can to obtain line directly be 50～250 nanometers, do not have the lithium cell anode material lithium manganate nano wire of reuniting.

Embodiment

Embodiment one:

At first, the preparation volumetric molar concentration is 5.0molL ^-1NaOH solution, by Na: the Mn mol ratio is that 0.44: 2 stoichiometric ratio takes by weighing Mn ₃O ₄With Mn ₃O ₄Mix with NaOH solution, ultra-sonic dispersion 15 minutes places hydrothermal reaction kettle, is heated to 225 ℃, constant temperature 3 days～5 days; Product in the reactor is washed suction filtration repeatedly, after the vacuum drying at room temperature, make LiMn ₂O ₄Presoma nano wire LiNa _0.44Mn ₂O ₄Secondly, be to take by weighing LiNa at 1: 0.88: 0.12 in molar ratio _0.44Mn ₂O ₄, LiNO ₃, LiClH ₂O puts into ball grinder with above-mentioned raw materials, the agate mill ball of packing into, and ball milling 4 hours obtains mixed slurry, is placed in the porcelain boat, puts into resistance wire horizontal pipe stove, with 3 ℃ of min ^-1Temperature rise rate be heated to 500 ℃, be incubated 1 hour～5 hours, cool to room temperature then with the furnace, the black product that obtains is washed suction filtration repeatedly, vacuum drying at room temperature 4 hours; At last, dried product is placed porcelain boat, put into resistance wire horizontal pipe stove, with 3 ℃ of min ^-1Temperature rise rate be heated to 800 ℃, be incubated 1 hour～3 hours; Cool to room temperature then with the furnace, grinding in agate mortar and obtaining line directly is the LiMn of 80～200 nanometers ₂O ₄Nano wire.

Embodiment two:

At first, the preparation volumetric molar concentration is 5.0molL ^-1NaOH solution, by Na: the Mn mol ratio is that 0.44: 2 stoichiometric ratio takes by weighing Mn ₃O ₄With Mn ₃O ₄Mix with NaOH solution, ultra-sonic dispersion 20 minutes places hydrothermal reaction kettle, is heated to 215 ℃, constant temperature 4 days; Product in the reactor is washed suction filtration repeatedly, after the vacuum drying at room temperature, make LiMn ₂O ₄Presoma nano wire LiNa _0.44Mn ₂O ₄Secondly, be to take by weighing LiNa at 1: 0.88: 0.12 in molar ratio _0.44Mn ₂O ₄, LiNO ₃, LiClH ₂O puts into ball grinder with above-mentioned raw materials, the agate mill ball of packing into, and ball milling 4 hours obtains mixed slurry, is placed in the porcelain boat, puts into resistance wire horizontal pipe stove, with 3 ℃ of min ^-1Temperature rise rate be heated to 500 ℃, be incubated 4 hours～5 hours, cool to room temperature then with the furnace, the black product that obtains is washed suction filtration repeatedly, vacuum drying at room temperature 4 hours; At last, dried product is placed porcelain boat, put into resistance wire horizontal pipe stove, with 3 ℃ of min ^-1Temperature rise rate be heated to 800 ℃, be incubated 1 hour～3 hours; Cool to room temperature then with the furnace, grinding in agate mortar and obtaining line directly is the LiMn of 50～100 nanometers ₂O ₄Nano wire.

Embodiment three:

At first, the preparation volumetric molar concentration is 5.0molL ^-1NaOH solution, by Na: the Mn mol ratio is that 0.44: 2 stoichiometric ratio takes by weighing Mn ₃O ₄With Mn ₃O ₄Mix with NaOH solution, ultra-sonic dispersion 20 minutes places hydrothermal reaction kettle, is heated to 205 ℃, constant temperature 2 days; Product in the reactor is washed suction filtration repeatedly, after the vacuum drying at room temperature, make LiMn ₂O ₄Presoma nano wire LiNa _0.44Mn ₂O ₄Secondly, be to take by weighing LiNa at 1: 0.88: 0.12 in molar ratio _0.44Mn ₂O ₄, LiNO ₃, LiClH ₂O puts into ball grinder with above-mentioned raw materials, the agate mill ball of packing into, and ball milling 4 hours obtains mixed slurry, is placed in the porcelain boat, puts into resistance wire horizontal pipe stove, with 5 ℃ of min ^-1Temperature rise rate be heated to 500 ℃, be incubated 3 hours～5 hours, cool to room temperature then with the furnace, the black product that obtains is washed suction filtration repeatedly, vacuum drying at room temperature 4 hours; At last, dried product is placed porcelain boat, put into resistance wire horizontal pipe stove, with 5 ℃ of min ^-1Temperature rise rate be heated to 800 ℃, be incubated 1 hour～3 hours; Cool to room temperature then with the furnace, grinding in agate mortar and obtaining line directly is the LiMn of 100～200 nanometers ₂O ₄Nano wire.

Claims

1. the preparation method of a lithium cell anode material lithium manganate nano wire is characterized in that, may further comprise the steps:

At first, the preparation volumetric molar concentration is 2.5-10.0molL ^-1NaOH solution, press Na _0.44Mn ₂O ₄Stoichiometric ratio takes by weighing Mn ₃O ₄With Mn ₃O ₄Mix with NaOH solution, ultra-sonic dispersion 10-20 minute, place hydrothermal reaction kettle, be heated to 205-225 ℃, constant temperature 3-5 days; Product in the reactor is washed suction filtration repeatedly, after the vacuum drying at room temperature, make LiMn ₂O ₄Presoma LiNa _0.44Mn ₂O ₄Nano wire;

Secondly, be to take by weighing presoma LiNa at 1: 0.88: 0.12 in molar ratio _0.44Mn ₂O ₄Nano wire, LiNO ₃, LiClH ₂O puts into ball grinder with above-mentioned raw materials, the agate mill ball of packing into, and ball milling 2-4 hour, obtain mixed slurry, be placed in the porcelain boat, put into the horizontal pipe stove, with 1-5 ℃ of min ^-1Temperature rise rate be heated to 450-550 ℃, be incubated 1-5 hour, cool to room temperature then with the furnace, the black product that obtains is washed suction filtration repeatedly, vacuum drying at room temperature 2-4 hour;

At last, dried product is placed porcelain boat, put into the horizontal pipe stove, with 1-5 ℃ of min ^-1Temperature rise rate be heated to 750-850 ℃, be incubated 1-4 hour; Cool to room temperature then with the furnace, in agate mortar, grind and obtain LiMn ₂O ₄Nano wire.

2. the method for preparing the lithium cell anode material lithium manganate nano wire according to claim 1 is characterized in that, the heating member of described horizontal pipe stove is the Fe-Cr-Al resistance wire.