CN114655984A - Indium-niobium oxide cathode material of lithium ion battery and preparation method thereof - Google Patents

Abstract

The invention belongs to the technical field of batteries, and discloses an indium niobium oxide negative electrode material for a lithium ion battery and a preparation method thereof. The invention uses niobium source and indium source as raw materials, adds additives, and dissolves them in suitable solvents respectively; after mixing and stirring them evenly, they are placed in a high-temperature reaction kettle for solvothermal reaction, and the precipitate is washed and dried for many times to obtain Precursor; the obtained precursor material is transferred to a tube furnace, calcined in different atmospheres, and cooled with the furnace to obtain a bulk indium niobium oxide negative electrode material, and the obtained material has excellent rate performance and cycle stability .

Description

A kind of lithium ion battery indium niobium oxide negative electrode material and preparation method thereof

technical field

The invention belongs to the technical field of negative electrode materials for lithium ion batteries, and particularly relates to an indium niobium oxide negative electrode material and a preparation method thereof.

Background technique

At present, most commercial lithium-ion battery anode materials use graphite. However, the rate performance of graphite is not ideal, and the lithium intercalation potential is relatively low. It is easy to form lithium dendrites during the rapid charge and discharge process, which has serious safety hazards and is difficult to meet the growing development. The requirements for it in the field of energy storage; the working voltage of Li ₄ Ti ₅ O ₁₂ with a spinel structure is about 1.5V, and there will be no SEI film and lithium dendrites during the charging and discharging process, so its rate performance is excellent. The cycling performance is very good, however the low specific capacity (175mAh g ^-1 ) limits its development.

Niobium-based oxides are competitive candidates for anode materials for Li-ion batteries due to their high theoretical specific capacity (~400mAh g ^-1 ) and their high lithium-deintercalation potential (1~2V). The huge niobium-based group provides a lot of references for its energy storage performance research, and the development of a new niobium-based group system is of great significance for its further research. Since the ionic radii of indium and niobium are not much different, the introduction of indium ions will not have a great impact on the material structure. On the contrary, due to the introduction of metal indium ions, the material structure layer will migrate to form a stable shear phase structure, which is very effective. It is beneficial to the rapid de-intercalation of Li ⁺ , and the utilization rate of niobium is greatly improved. At the same time, the self-doping and calcination conditions can further tune the material structure and electronic properties. Solvothermal method is a special form of hydrothermal method, which has the advantages of high purity of synthetic nanomaterials, good grain development, low degree of agglomeration, and narrow particle size distribution. Various additives have a certain degree of soft template effect and the role of regulating the physical and chemical properties of the solution (such as pH value, solution surface tension, dispersing ability). Therefore, the present invention proposes to prepare the indium niobium oxide negative electrode material by a solvothermal method, and there is no relevant report at present.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide an indium niobium oxide negative electrode material and a preparation method thereof, and further modify it, so as to obtain an indium niobium oxide negative electrode material with excellent electrochemical performance.

Technical scheme of the present invention:

A preparation method of an indium niobium oxide negative electrode material for a lithium ion battery, comprising the following steps:

The niobium source, the indium source and the additive were dissolved in the solvent respectively, and then the solutions were mixed uniformly. The mixed solution was stirred for 2 to 24 hours and then transferred to a high temperature reaction kettle for solvothermal reaction. The obtained products were filtered with deionized water and The solid precursor is obtained by washing with absolute ethanol for many times and drying to obtain a solid precursor; then the solid precursor is placed in a temperature-controlled tube furnace, calcined in different atmospheres, and cooled with the furnace to obtain a bulk indium niobium oxide negative electrode material. .

The niobium source includes at least one of niobium pentachloride, niobium oxalate and its complex, niobium hydroxide and niobium acetate;

The indium source includes one or more of indium trichloride, indium nitrate and indium acetate.

The additives include sodium lauryl sulfate, polyether F127, sodium dodecylbenzenesulfonate, N-(dodecyl) lysine, polyvinylpyrrolidone, triethanolamine, ammonia, urea, sodium hydroxide , one or more of amino acids and their salts.

The solvent is at least one of deionized water and absolute ethanol.

In the mixed solution, the concentrations of the niobium source and the indium source solution are both 0.01-0.1 mol L ⁻¹ ; the mass ratio of additive:total solvent=(1-7):(100).

The solvothermal reaction temperature is 160-240 DEG C, and the reaction time is 6-48h.

The atmosphere includes at least one of air, oxygen, argon, nitrogen, and a mixture of hydrogen and argon; the heating rate is 1-10°C min ^-1 ; the calcination temperature is 600-1300°C, and the calcination time is 2 to 24 hours.

In the indium niobium oxide negative electrode material, the stoichiometric ratio of In:Nb:O is x:(2-x):(5-x), wherein 0.01≤x<1, and the excess coefficients of In and Nb are respectively 0 ~0.08 and 0 to 0.1.

When the atmosphere is argon gas, nitrogen gas or a mixture of hydrogen and argon, the indium niobium oxide negative electrode material is oxygen-deficient indium niobium oxide.

The beneficial effects that the present invention has are:

The invention adopts the solvothermal method to prepare the indium niobium oxide electrode material. The obtained material has a uniform bulk morphology, which makes it have a large specific surface area; the stable and open ReO ₃ crystal shear structure makes the material have excellent cycle stability and rate performance; the introduction of indium ions makes the niobium-based material. More niobium is active to participate in the redox reaction, which promotes a greater degree of Nb ³⁺ /Nb ⁴⁺ reaction; at the same time, the stoichiometric ratio of In _x Nb _2-x O _5-x can be achieved by controlling the excess coefficients of In and Nb The cationic self-doping can further control the crystal structure and improve the electrochemical performance of the material; and calcination in an inert atmosphere can make the material generate abundant anion vacancies, improve its electronic conductivity, and further improve its rate capability. The indium niobium oxide electrode material prepared by the invention has high charge specific capacity, good cycle stability and excellent rate performance as the negative electrode material of lithium ion battery.

Description of drawings

FIG. 1 is an XRD pattern of the In _0.5 Nb _24.5 O ₆₂ negative electrode material in Example 1. FIG.

FIG. 2 is a SEM image of the In _0.5 Nb _24.5 O ₆₂ negative electrode material in Example 1. FIG.

FIG. 3 is a charge-discharge curve diagram of the In _0.5 Nb _24.5 O ₆₂ negative electrode material in Example 1. FIG.

FIG. 4 is an XRD pattern of the In _0.5 Nb _24.5 O ₆₂ negative electrode material in Example 2. FIG.

FIG. 5 is an XRD pattern of the In _0.5 Nb _24.99 O _63.225 negative electrode material in Example 3. FIG.

6 is a graph of the rate performance of the In _0.5 Nb _24.5 O _62-x negative electrode material in Example 4. FIG.

Detailed ways

Example 1

Preparation of stoichiometric In _0.5 Nb _24.5 O ₆₂ anode material:

Using niobium pentachloride and indium trichloride as raw materials, selecting polyether F127 as additive, and controlling x=0.04 in In _x Nb _2-x O _5-x , the stoichiometric ratio In _0.5 Nb _24.5 O ₆₂ negative electrode material was prepared. Take 0.004 mol of niobium pentachloride, weigh 0.2 g of polyether, and mix them after they are dissolved completely. The mixed solution was put into a high temperature reaction kettle and put into a constant temperature oven for reaction, the reaction temperature was 200°C, and the reaction time was 24h. After the reaction, the precipitate was taken out, washed with water and absolute ethanol for several times, and then placed in an oven to dry. The dried samples were calcined in a tube furnace in an air atmosphere. The calcination temperature was 1000 °C, the calcination time was 6 h, and the heating rate was 4 °C min ^-1 . After the heat preservation was completed, the In _0.5 Nb _24.5 O ₆₂ negative electrode was obtained by cooling with the furnace. Material. The XRD pattern of the obtained material is shown in Figure 1, and its structure matches that of PDF#72-1121. The refinement results show that the material has a _ReO3 crystal shear structure and is a monoclinic system. The SEM image is shown in Fig. 2, and the obtained material is block-like particles. The charge-discharge curve is shown in Fig. 3, and the first charge specific capacity at 0.1C is 414.1mAh g ^-1 .

Example 2

Preparation of In _0.5 Nb _24.5 O ₆₂ Anode Materials with Different Crystal Forms:

Using niobium pentachloride and indium trichloride as raw materials, selecting polyether F127 as additive, and controlling x=0.04 in In _x Nb _2-x O _5-x , the stoichiometric ratio In _0.5 Nb _24.5 O ₆₂ negative electrode material was prepared. Take 0.004 mol of niobium pentachloride, weigh 0.2 g of polyether, and mix them after they are dissolved completely. The mixed solution was put into a high temperature reaction kettle and put into a constant temperature oven for reaction, the reaction temperature was 200°C, and the reaction time was 24h. After the reaction, the precipitate was taken out, washed with water and absolute ethanol for several times, and then placed in an oven to dry. The dried samples were calcined in a tube furnace in an air atmosphere. The _calcination temperature was 900 °C, the _calcination time was 6 h, and the heating rate was 4 °C _min ^-1 . Material. The XRD pattern of the obtained material is shown in Figure 4, and its structure matches that of PDF#30-0873, which is an orthorhombic system, indicating that the material is calcined at different temperatures to obtain samples of different crystal forms and different space groups.

Example 3

Preparation of cationic self-doping In _0.5 Nb _24.5 O ₆₂ anode material:

Using niobium pentachloride and indium trichloride as raw materials, selecting polyether F127 as an additive, and controlling x=0.04 in In _x Nb _2-x O _5-x , on the basis of Example 1, the excess coefficient of Nb is controlled as 0.02, prepare Nb ⁵⁺ doped In _0.5 Nb _24.5 O ₆₂ negative electrode material, namely In _0.5 Nb _24.99 O _63.225 . The rest of the conditions remain the same. The material structure still matches that of PDF#72-1121 and is monoclinic, as shown in Figure 5; however, the unit cell parameters and unit cell volume are changed, the cationic local electronic structure is changed, and the rate performance of the material is improved.

Example 4

Preparation of In _0.5 Nb _24.5 O ₆₂ Negative Material for Oxygen Vacancy Tuning:

Using niobium pentachloride and indium trichloride as raw materials, selecting polyether F127 as additive, and controlling x=0.04 in In _x Nb _2-x O _5-x , the stoichiometric ratio In _0.5 Nb _24.5 O ₆₂ negative electrode material was prepared. Take 0.004 mol of niobium pentachloride, weigh 0.2 g of polyether, and mix them after they are dissolved completely. The mixed solution was put into a high temperature reaction kettle and put into a constant temperature oven for reaction, the reaction temperature was 200°C, and the reaction time was 24h. After the reaction, the precipitate was taken out, washed with water and absolute ethanol for several times, and then placed in an oven to dry. The dried samples were calcined in a tube furnace under an argon atmosphere. The calcination temperature was 1000 °C, the _calcination time was 6 h, and the heating rate was 4 °C min ^-1 . _24.5 O ₆₂ negative electrode material. The electronic conductivity of the material is enhanced and the rate performance is improved, as shown in Figure 6.

Claims (9)

1. a preparation method of lithium ion battery indium niobium oxide negative electrode material, is characterized in that, concrete steps are as follows: (1) Dissolve the niobium source, the indium source and the additive in the solvent, respectively, and then mix the solutions uniformly. The mixed solution is continuously stirred and then transferred to a high-temperature reactor for solvothermal reaction. The obtained product is filtered with deionized water and Washed with anhydrous ethanol for many times, and dried to obtain a solid precursor; (2) The precursor obtained in step (1) is placed in a temperature-programmed tube furnace, calcined in different atmospheres, and cooled with the furnace to obtain a bulk indium niobium oxide negative electrode material. 2. preparation method according to claim 1, is characterized in that, in step (1), described niobium source comprises at least in niobium pentachloride, niobium oxalate and its complex, niobium hydroxide, niobium acetate One; the indium source includes one or more of indium trichloride, indium nitrate and indium acetate. 3. preparation method according to claim 1 is characterized in that, in step (1), described additive comprises sodium dodecyl sulfate, polyether F127, sodium dodecylbenzenesulfonate, N-( Dodecanoyl) lysine, polyvinylpyrrolidone, triethanolamine, ammonia, urea, sodium hydroxide, amino acid and one or more of its salts. 4. The preparation method according to claim 1, wherein in step (1), the solvent is at least one of deionized water and absolute ethanol. 5. The preparation method according to claim 1, wherein in step (1), in the mixed solution, the concentrations of the niobium source and the indium source solution are both 0.01-0.1 mol L ^-1 ; the additive: solvent The mass ratio of the total amount=(1～7):(100), and the stirring time is 2～24h. 6 . The preparation method according to claim 1 , wherein in step (1), the solvothermal reaction temperature is 160-240° C., and the reaction time is 6-48 h. 7 . 7. The preparation method according to claim 1, wherein in step (2), the atmosphere comprises at least one of air, oxygen, argon, nitrogen, and a hydrogen-argon mixture; the heating rate The calcination temperature is 1～10℃min ⁻¹ ; the calcination temperature is 600～1300℃, and the calcination time is 2～24h. 8. A lithium ion battery indium niobium oxide negative electrode material, characterized in that, it is obtained according to the preparation method described in any one of claims 1 to 7, and in the indium niobium oxide negative electrode material, In: The stoichiometric ratio of Nb:O is x:(2-x):(5-x), where 0.01≤x<1, and the excess coefficients of In and Nb are 0-0.08 and 0-0.1, respectively. 9 . The lithium ion battery indium niobium oxide negative electrode material according to claim 8 , wherein when the atmosphere in step (2) is argon, nitrogen or hydrogen-argon mixture, the obtained indium niobium oxide negative electrode material It is oxygen-deficient indium niobium oxide.

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