A synthetic method of sodium ferric sulfate positive electrode material

Abstract

A synthetic method of sodium ferric sulfate positive electrode material includes the following steps: (1) adding Na2SO4 and FeSO 4 *7 H 2 O into the mixture of Na2SO4 and FeSO 4 * 7 H 2 O according tothe molar ratio of 1: 1.4 to 2.0) weigh and mixing, adde a carbon source into that mixture, wherein the mass of the carbon source is 0.75 to 1.5 wt% of the mass of the mixture, uniformly mixing, high-energy ball mil for several times, each time for 20 to 30 minutes, and obtaining highly dispersed uniform powder; (2) calcining the ball-milled homogeneous powder in an inert atmosphere of high purity argon at 320-380 DEG C for 10-30h, cooling the product to room temperature with the furnace, and then grinding the product manually for 3-10min until no large particles are seen in the naked eye, soas to obtain the final material. The synthesis method of the invention is simple, the operation flow is short, and the product performance is excellent.

Description

technical field

[0001] The invention belongs to the field of preparation of positive electrode materials for lithium ion batteries, in particular to a 2 SO 4 and FeSO 4 ·7H 2 O as the main material to synthesize Na 2+2x Fe 2-x (SO 4 ) 3 material method. Background technique

[0002] The environmental and energy crisis is becoming more and more severe, and the development of low-cost and environmentally friendly new energy sources and energy storage and conversion have attracted the attention of governments and scientific and technological researchers from various countries. The rapid rise of lithium-ion secondary batteries, the research of its cathode materials mainly focus on the layered oxide LiMO 2 (M=Co, Mn, Ni), polyanionic LiFePO 4 , high voltage Li[Ni 0.5 mn 1.5 ]O 4 and lithium-rich material xLi 2 MnO 3 ·(1-x)LiMO 2 Wait. Among many lithium ion cathode materials, lithium iron phosphate LiFePO 4 and ternary layered material LiNi x co y mn z o 2 be...

Examples

Embodiment 1

[0022] The synthetic method of sodium ferric sulfate cathode material, comprises the following steps:

[0023] Step 1: Na 2 SO 4 and FeSO 4 ·7H 2 O is weighed and mixed according to the molar ratio of 1:1.4, and the graphene carbon source is added. powder;

[0024] Step 2: After calcining the uniform powder after ball milling in Step 1 in an inert atmosphere of high-purity argon at 320-330°C for 20 hours, the product is cooled to room temperature with the furnace, and then manually ground for 3 minutes until no large particles are seen with the naked eye. final material.

Embodiment 2

[0026] The synthetic method of sodium ferric sulfate cathode material, comprises the following steps:

[0027] Step 1: Na 2 SO 4 and FeSO 4 ·7H 2 O is weighed and mixed according to the molar ratio of 1:2.0, and the carbon black Super P carbon source is added, whose mass is 1%wt of the mass of the mixture. After 25 minutes, a highly dispersed uniform powder is obtained;

[0028] Step 2: After calcining the uniform powder after ball milling in Step 1 in an inert atmosphere of high-purity argon at 350-360°C for 30 hours, the product is cooled to room temperature with the furnace, and then manually ground for 5 minutes until no large particles are visible to the naked eye. final material.

Embodiment 3

[0030] The synthetic method of sodium ferric sulfate cathode material, comprises the following steps:

[0031] Step 1: Na 2 SO 4 and FeSO 4 ·7H 2 O After weighing and mixing according to the molar ratio of 1:2, add graphene carbon source, the mass of which is 1.5%wt of the mass of the mixture, after mixing evenly, ethanol is used as a grinding aid, wet high-energy ball milling several times, used for high-energy ball milling The diameter of the steel ball is 4mm, the mass ratio of the steel ball to the raw material is 7:2, and the ball milling rate is 500rad / min, each 20min, to obtain highly dispersed uniform powder;

[0032] Step 2: Heat the uniform powder after ball milling in Step 1 to 380°C at a slow heating rate of 3.5°C / min, then calcinate at this temperature and in an inert atmosphere of high-purity argon for 10 hours, and then cool the product to At room temperature, grind manually for another 10 minutes until no large particles are seen with the naked eye, which i...

technical field

[0001] The invention belongs to the field of preparation of positive electrode materials for lithium ion batteries, in particular to a 2 SO 4 and FeSO 4 ·7H 2 O as the main material to synthesize Na 2+2x Fe 2-x (SO 4 ) 3 material method. Background technique

[0002] The environmental and energy crisis is becoming more and more severe, and the development of low-cost and environmentally friendly new energy sources and energy storage and conversion have attracted the attention of governments and scientific and technological researchers from various countries. The rapid rise of lithium-ion secondary batteries, the research of its cathode materials mainly focus on the layered oxide LiMO 2 (M=Co, Mn, Ni), polyanionic LiFePO 4 , high voltage Li[Ni 0.5 mn 1.5 ]O 4 and lithium-rich material xLi 2 MnO 3 ·(1-x)LiMO 2 Wait. Among many lithium ion cathode materials, lithium iron phosphate LiFePO 4 and ternary layered material LiNi x co y mn z o 2 be...

Examples

Embodiment 1

[0022] The synthetic method of sodium ferric sulfate cathode material, comprises the following steps:

[0023] Step 1: Na 2 SO 4 and FeSO 4 ·7H 2 O is weighed and mixed according to the molar ratio of 1:1.4, and the graphene carbon source is added. powder;

[0024] Step 2: After calcining the uniform powder after ball milling in Step 1 in an inert atmosphere of high-purity argon at 320-330°C for 20 hours, the product is cooled to room temperature with the furnace, and then manually ground for 3 minutes until no large particles are seen with the naked eye. final material.

Embodiment 2

[0026] The synthetic method of sodium ferric sulfate cathode material, comprises the following steps:

[0027] Step 1: Na 2 SO 4 and FeSO 4 ·7H 2 O is weighed and mixed according to the molar ratio of 1:2.0, and the carbon black Super P carbon source is added, whose mass is 1%wt of the mass of the mixture. After 25 minutes, a highly dispersed uniform powder is obtained;

[0028] Step 2: After calcining the uniform powder after ball milling in Step 1 in an inert atmosphere of high-purity argon at 350-360°C for 30 hours, the product is cooled to room temperature with the furnace, and then manually ground for 5 minutes until no large particles are visible to the naked eye. final material.

Embodiment 3

[0030] The synthetic method of sodium ferric sulfate cathode material, comprises the following steps:

[0031] Step 1: Na 2 SO 4 and FeSO 4 ·7H 2 O After weighing and mixing according to the molar ratio of 1:2, add graphene carbon source, the mass of which is 1.5%wt of the mass of the mixture, after mixing evenly, ethanol is used as a grinding aid, wet high-energy ball milling several times, used for high-energy ball milling The diameter of the steel ball is 4mm, the mass ratio of the steel ball to the raw material is 7:2, and the ball milling rate is 500rad / min, each 20min, to obtain highly dispersed uniform powder;

[0032] Step 2: Heat the uniform powder after ball milling in Step 1 to 380°C at a slow heating rate of 3.5°C / min, then calcinate at this temperature and in an inert atmosphere of high-purity argon for 10 hours, and then cool the product to At room temperature, grind manually for another 10 minutes until no large particles are seen with the naked eye, which i...