Preparation method for reducing sulfur content of NCM ternary precursor

Abstract

The invention belongs to the field of lithium ion battery materials, and particularly discloses a preparation method for reducing the sulfur content of an NCM ternary precursor. The preparation methodcomprises the following steps: obtaining a nickel-cobalt-manganese ternary solution containing Ni<2+>, Co<2+>, Mn<2+>, SO4<2->, a surfactant and a reducing agent; and then carrying out co-precipitation to prepare the NCM ternary precursor. According to the preparation method provided by the invention, a processing idea of carrying out washing after a precursor is synthesized in the prior art is changed, and a processing idea of controlling sulfur introduction from a synthesis stage is provided. The surfactant and the reducing agent are creatively added into a NCM raw material solution, and co-precipitation is carried out under the solution system, so that the sulfur content of the obtained precursor can be remarkably reduced.

Description

technical field

[0001] The invention relates to the technical field of preparation of lithium battery materials, in particular to a preparation method for reducing the sulfur content of an NCM ternary precursor. Background technique

[0002] The ternary precursor is an important raw material for the production of ternary cathode materials for lithium-ion batteries. The morphology, particle size distribution, specific surface area, impurity content, tap density and other parameters of the precursor directly determine the physical and electrochemical properties of the cathode material. It can be said that 60% of the technical content of the positive electrode material is in the precursor process.

[0003] Industrial precursors are mainly synthesized by wet method, with NiSO 4 、CoSO 4 , MnSO 4 It is a mixed salt solution, liquid caustic soda is used as a precipitating agent, and ammonia water is used as a complexing agent.

[0004] In the existing method, the surface and in...

Examples

Embodiment 1

[0044] Weigh a certain amount of nickel sulfate, cobalt sulfate and manganese sulfate in proportion, dissolve them in 4L deionized water, configure a 523 type (NiCoMn molar ratio) salt solution with a concentration of 2mol / L, add 0.9ml ethanolamine and 1g ascorbic acid. The solution after stirring evenly passes through the iron remover and microporous filter in turn to obtain the solution as ternary solution a; measure a certain amount of 32% liquid caustic soda, dilute it with pure water to 4L, and use a NaOH solution with a concentration of 5mol / L as a precipitate Agent b; Weigh 444ml of 25% ammonia water, add 156ml of water to dilute to obtain 600ml of 18% ammonia solution as precipitant c.

[0045] in N 2 Bottom water was added to the protected 2L reactor, the temperature was raised to 55° C. and stirring was started at 700 rpm. Add solutions b and c, so that the pH value in the kettle is 10.4, and the ammonia content is 9g / L. Use a peristaltic pump to pump solution a i...

Embodiment 2

[0047] Take a certain amount of nickel sulfate, cobalt sulfate and manganese sulfate in proportion, be dissolved in 4L deionized water, be configured into a 622 type (NiCoMn molar ratio) salt solution with a concentration of 1.8mol / L, add 0.9ml ethanolamine, 0.8ml diethanolamine and 1g ascorbic acid. The solution after stirring evenly passes through the iron remover and microporous filter in turn to obtain the solution as ternary solution a; measure a certain amount of 32% liquid caustic soda, dilute it with pure water to 3L, and use a NaOH solution with a concentration of 5mol / L as a precipitate Agent b; Weigh 444ml of 25% ammonia water and add 156ml of water to dilute to obtain 600ml of 18% ammonia solution as precipitant c.

[0048] in N 2 Bottom water was added to the protected 2L reactor, the temperature was raised to 60° C., and stirring was started at a speed of 750 rpm. Add solutions b and c, so that the pH value in the kettle is 10.6, and the ammonia content is 9.5g...

Embodiment 3

[0050] Weigh a certain amount of nickel sulfate, cobalt sulfate and manganese sulfate in proportion, dissolve them in 4L of deionized water, and configure the 811 type (NiCoMn molar ratio) salt solution with a concentration of 1.8mol / L, and add 0.9ml of diethanolamine to the solution , 1 g of ascorbic acid and 1 g of glucose. The solution after stirring evenly passes through the iron remover and microporous filter in turn to obtain the solution as ternary liquid a; measure a certain amount of 32% liquid caustic soda, dilute it into 2L with pure water, and use NaOH solution with a concentration of 8mol / L as the precipitate Agent b; weigh 369ml of 25% ammonia water, add 131ml of water to dilute, and obtain 500ml of 18% ammonia solution as precipitant c.

[0051] in N 2 Bottom water was added to the protected 2L reactor, the temperature was raised to 65° C., and stirring was started at a speed of 800 rpm. Add solutions b and c, so that the pH value in the kettle is 10.8, and th...

technical field

[0001] The invention relates to the technical field of preparation of lithium battery materials, in particular to a preparation method for reducing the sulfur content of an NCM ternary precursor. Background technique

[0002] The ternary precursor is an important raw material for the production of ternary cathode materials for lithium-ion batteries. The morphology, particle size distribution, specific surface area, impurity content, tap density and other parameters of the precursor directly determine the physical and electrochemical properties of the cathode material. It can be said that 60% of the technical content of the positive electrode material is in the precursor process.

[0003] Industrial precursors are mainly synthesized by wet method, with NiSO 4 、CoSO 4 , MnSO 4 It is a mixed salt solution, liquid caustic soda is used as a precipitating agent, and ammonia water is used as a complexing agent.

[0004] In the existing method, the surface and in...

Examples

Embodiment 1

[0044] Weigh a certain amount of nickel sulfate, cobalt sulfate and manganese sulfate in proportion, dissolve them in 4L deionized water, configure a 523 type (NiCoMn molar ratio) salt solution with a concentration of 2mol / L, add 0.9ml ethanolamine and 1g ascorbic acid. The solution after stirring evenly passes through the iron remover and microporous filter in turn to obtain the solution as ternary solution a; measure a certain amount of 32% liquid caustic soda, dilute it with pure water to 4L, and use a NaOH solution with a concentration of 5mol / L as a precipitate Agent b; Weigh 444ml of 25% ammonia water, add 156ml of water to dilute to obtain 600ml of 18% ammonia solution as precipitant c.

[0045] in N 2 Bottom water was added to the protected 2L reactor, the temperature was raised to 55° C. and stirring was started at 700 rpm. Add solutions b and c, so that the pH value in the kettle is 10.4, and the ammonia content is 9g / L. Use a peristaltic pump to pump solution a i...

Embodiment 2

[0047] Take a certain amount of nickel sulfate, cobalt sulfate and manganese sulfate in proportion, be dissolved in 4L deionized water, be configured into a 622 type (NiCoMn molar ratio) salt solution with a concentration of 1.8mol / L, add 0.9ml ethanolamine, 0.8ml diethanolamine and 1g ascorbic acid. The solution after stirring evenly passes through the iron remover and microporous filter in turn to obtain the solution as ternary solution a; measure a certain amount of 32% liquid caustic soda, dilute it with pure water to 3L, and use a NaOH solution with a concentration of 5mol / L as a precipitate Agent b; Weigh 444ml of 25% ammonia water and add 156ml of water to dilute to obtain 600ml of 18% ammonia solution as precipitant c.

[0048] in N 2 Bottom water was added to the protected 2L reactor, the temperature was raised to 60° C., and stirring was started at a speed of 750 rpm. Add solutions b and c, so that the pH value in the kettle is 10.6, and the ammonia content is 9.5g...

Embodiment 3

[0050] Weigh a certain amount of nickel sulfate, cobalt sulfate and manganese sulfate in proportion, dissolve them in 4L of deionized water, and configure the 811 type (NiCoMn molar ratio) salt solution with a concentration of 1.8mol / L, and add 0.9ml of diethanolamine to the solution , 1 g of ascorbic acid and 1 g of glucose. The solution after stirring evenly passes through the iron remover and microporous filter in turn to obtain the solution as ternary liquid a; measure a certain amount of 32% liquid caustic soda, dilute it into 2L with pure water, and use NaOH solution with a concentration of 8mol / L as the precipitate Agent b; weigh 369ml of 25% ammonia water, add 131ml of water to dilute, and obtain 500ml of 18% ammonia solution as precipitant c.

[0051] in N 2 Bottom water was added to the protected 2L reactor, the temperature was raised to 65° C., and stirring was started at a speed of 800 rpm. Add solutions b and c, so that the pH value in the kettle is 10.8, and th...

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