CN-122010074-A - Method for producing manganese iron phosphate particles

CN122010074ACN 122010074 ACN122010074 ACN 122010074ACN-122010074-A

Abstract

The present invention provides a method for producing manganese iron phosphate particles, comprising a step of mixing and stirring a metal powder containing carbon, iron and manganese with a phosphoric acid compound in a protic solvent to obtain a slurry containing manganese iron phosphate particles, and a step of drying the slurry to obtain manganese iron phosphate particles.

Inventors

Ma Yuanlongde

Assignees

丰田自动车株式会社

Dates

Publication Date: 20260512
Application Date: 20251110
Priority Date: 20241111

Claims (4)

1. A method for producing manganese iron phosphate particles, comprising: A step of mixing and stirring a metal powder containing carbon, iron and manganese and a phosphoric acid compound in a protic solvent to obtain a slurry containing manganese iron phosphate particles, and And drying the slurry to obtain the manganese iron phosphate particles.
2. The method for producing manganese iron phosphate particles according to claim 1, wherein a molar ratio of iron to manganese in the metal powder is 20 to 30:70 to 80.
3. The method for producing ferromanganese phosphate particles according to claim 1 or 2, wherein the metal powder is ferromanganese.
4. The method for producing manganese iron phosphate particles according to claim 1 or 2, wherein the content of carbon in the metal powder is 4 mass% or more and 7 mass% or less.

Description

Method for producing manganese iron phosphate particles Technical Field The present disclosure relates to a method of manufacturing manganese iron phosphate particles. Background JP-A2014-65641 discloses a method of producing iron phosphate by reacting iron with phosphorus to produce a precipitate and washing the precipitate. Further, a method for producing lithium iron phosphate by reacting the iron phosphate obtained as described above with a lithium compound is also disclosed. Japanese patent application laid-open No. 2016-81866 discloses a method for producing lithium iron manganese phosphate by a hydrothermal reaction. Disclosure of Invention Lithium iron phosphate and lithium manganese iron phosphate are used as the positive electrode active material. As disclosed in japanese patent application laid-open No. 2014-65641, as for lithium iron phosphate, there is iron phosphate as a suitable precursor. On the other hand, for lithium iron manganese phosphate, no suitable precursor exists, and a method that can be manufactured at low cost has not been established yet. Further, as disclosed in Japanese patent application laid-open No. 2016-81866, lithium iron manganese phosphate can be produced by a hydrothermal reaction. On the other hand, the lithium manganese iron phosphate obtained by this production method has a large particle diameter, and further pulverization is necessary for the positive electrode active material, and it takes a long time to pulverize. The purpose of the present invention is to provide a method for producing ferromanganese phosphate particles, which can shorten the pulverizing time. [1] A method for producing ferromanganese phosphate particles, which comprises a step of mixing and stirring a metal powder containing carbon, iron and manganese and a phosphoric acid compound in a protic solvent to obtain a slurry containing ferromanganese phosphate particles, and a step of And drying the slurry to obtain the manganese iron phosphate particles. The metal powder containing carbon, iron and manganese and the phosphoric acid compound are mixed and stirred in a protic solvent to produce hydrocarbon gases such as hydrogen, methane and ethane. The manganese iron phosphate particles synthesized by the method accompanied by the generation of such gas spontaneously micronize due to gasification, and therefore do not need to be pulverized. As a result, reduction in the pulverizing time can be expected. In addition, as a suitable precursor of lithium iron manganese phosphate, it is expected to contribute to cost reduction. [2] The method for producing iron-manganese phosphate particles according to [1], wherein the molar ratio of iron to manganese in the metal powder is 20 to 30:70 to 80. [3] The method for producing manganese iron phosphate particles according to [1] or [2], wherein the metal powder is manganese iron. [4] The method for producing manganese iron phosphate particles according to any one of [1] to [3], wherein the content of carbon in the metal powder is 4% by mass or more and 7% by mass or less. The above and other objects, features, aspects and advantages of the present invention will become apparent from the following detailed description of the present invention which is to be read in connection with the accompanying drawings. Drawings Fig. 1 is a schematic flowchart of a method for producing lithium manganese iron phosphate according to the present embodiment. Fig. 2 is an example of SEM images of the iron-manganese phosphate particles of No. 1. Fig. 3 is an example of SEM images of iron-manganese phosphate particles of No. 2. Fig. 4 is an example of SEM images of the iron-manganese phosphate particles of No. 3. Fig. 5 is an example of SEM images of the manganese phosphate particles of No. 4. Fig. 6 is an example of SEM images of iron phosphate particles of No. 5. Fig. 7 is an example of SEM images of the iron-manganese phosphate particles of No. 6. Detailed Description Hereinafter, an embodiment of the present disclosure (hereinafter may be simply referred to as "the present embodiment") and an example of the present disclosure (hereinafter may be simply referred to as "the present example") will be described. However, the present embodiment and examples do not limit the technical scope of the present disclosure. The manganese iron phosphate particles manufactured in this example can be used to manufacture lithium manganese iron phosphate. Further, lithium iron manganese phosphate is suitable for use as an electrode active material for a secondary battery, in particular, as a positive electrode active material for a nonaqueous electrolyte secondary battery, for example. < Method for producing manganese iron phosphate particles > Fig. 1 is a schematic flowchart of a method for producing manganese iron phosphate particles according to the present embodiment. Hereinafter, the "method for producing manganese iron phosphate particles in the present embodiment" may be simply referre