Preparation method of amorphous mono-crystalline precursor oxide

[0032] As attached figure 1 As shown, a method for preparing an amorphous single crystal precursor oxide includes the following steps:

[0033] S1, prepare an amorphous ternary precursor with a composite structure by co-precipitation method;

[0034] S101, prepare metal salt solution and liquid caustic soda solution as raw and auxiliary material solutions for co-precipitation reaction, add pure water to the effective volume position of the reactor, heat the pure water in the reactor, and then add the prepared liquid caustic soda solution to adjust the pH range to obtain a total The bottom liquid of the precipitation reaction;

[0035] In S101, the metal salt solution is prepared by mixing nickel salt, cobalt salt, and manganese salt according to the traditional process. The total metal ion solubility of the prepared liquid caustic soda solution is 0.5-2mol/L. Concentration is 3-12mol/L, nickel salt, cobalt salt, manganese salt is at least one of nitrate, acetate, sulfate, citrate, chloride, carbonate, and oxalate, liquid caustic soda The solution is at least one of caustic soda, flake soda, soda ash, and heavy soda.

[0036] S102, adding the metal salt solution and the liquid caustic solution prepared in S101 to the reactor equipped with the bottom liquid at the same time for co-precipitation reaction. The materials in the reactor will flow out from the discharge port after 2-20 hours of co-precipitation reaction. The solid-liquid mixed amorphous ternary precursor slurry is washed with impurities, filtered, dehydrated, and dried to obtain an amorphous ternary precursor with a composite structure. The molecular formula is Ni x Co y Mn 1-x-y (OH) 2.

[0037] In S102, the temperature environment of the pure water in the reactor is 40-70℃, the pH range of the bottom liquid in the reactor is adjusted to 11.0-13.0, the speed of the internal stirring blade is 300-600r/min, and the flow rate of the metal salt solution It is 15-100L/h.

[0038] The heat treatment equipment adopts any one of a pusher furnace, a track furnace, a rotary furnace, and a steel belt furnace with functions of heating, cooling, and dust collection.

[0039] S2, the amorphous single crystal ternary precursor oxide is obtained after high temperature thermal decomposition of the amorphous ternary precursor prepared by S1 through heat treatment equipment;

[0040] In S2, the temperature environment of the high temperature thermal decomposition treatment is 500-1000℃, and the time of the high temperature thermal decomposition treatment is 8-36h. The heat treatment equipment adopts a pusher furnace, a rail furnace, and a return furnace with the functions of heating, cooling, and dust collection. Any one of converter and steel belt furnace, the temperature environment of high temperature thermal decomposition treatment is 500-1000℃, and the time of high temperature thermal decomposition treatment is 8-36h. The powder material after high temperature heat treatment is collected, crushed, classified and processed. After sieve and demagnetization, amorphous single crystal ternary precursor oxide is obtained, the molecular formula is Ni x Co y Mn 1-x-y O.

[0041] S3, adding lithium carbonate or lithium hydroxide to the amorphous single crystal ternary precursor oxide prepared by S2, and obtaining a ternary cathode material after high-temperature calcination and lithiation treatment.

[0042] The method of the present invention prepares amorphous single crystal precursor oxide as a new type of lithium ion battery cathode material, which can effectively improve the high temperature cycle performance and high temperature rate performance of the lithium ion battery, and improve the charging and discharging voltage platform of the existing ternary material to achieve effective The purpose of improving the high-temperature safety, cycling and high-rate charge-discharge performance of the existing lithium-ion battery system.

[0043] Due to the small surface area of ​​the amorphous single crystal precursor oxide and the good interfacial permeability of the particles, the diffusion efficiency and distribution uniformity of lithium ions are effectively improved, and it has better electrochemical cycling performance than traditional lithium ion battery cathode materials;

[0044] Since the surface of the amorphous single crystal precursor oxide has the characteristics of highly flat and smooth single crystal particles, the contact surface between the particle surface and the electrolyte is reduced after the lithium ion battery is assembled, and the corresponding side reaction of the cathode material and the electrolyte is significantly reduced. Effectively reduce the exothermic and outgassing phenomenon caused by side reactions, so that the battery has better high temperature safety performance and high temperature rate performance;

[0045] Amorphous single crystal precursor oxide with good surface electrochemical activity is prepared by heat treatment process. As a new type of lithium ion battery cathode material, it can effectively compensate for the low electrochemical activity of existing lithium battery cathode materials, and can better improve lithium The specific capacity of an ion battery.

[0046] Example 1:

[0047] First, add pure water to the reaction kettle and heat it to 40°C, then add the prepared liquid caustic soda solution to adjust the pH to 11.0, the stirring blade inside the reaction kettle is mixed evenly at a speed of 300r/min to prepare the bottom solution of the co-precipitation reaction , And then add 0.5mol/L metal salt solution and 3mol/L liquid caustic solution at a flow rate of 15L/h, after 2 hours of co-precipitation reaction in the reactor, flow out from the outlet of the reactor to obtain The solid-liquid mixed amorphous ternary precursor slurry is washed impurities, filtered, dehydrated, and dried to obtain an amorphous ternary precursor with a composite structure. The amorphous ternary precursor is subjected to high temperature thermal decomposition treatment at a temperature of 500 ℃ , The high temperature thermal decomposition treatment time is 8 hours, the powder material after high temperature heat treatment is collected, crushed, classified, sieved, and demagnetized to obtain the amorphous single crystal ternary precursor oxide, and then the amorphous single crystal three Lithium carbonate or lithium hydroxide is added to the meta-precursor oxide, and the ternary cathode material is obtained through high-temperature calcination and lithiation treatment.

[0048] Example 2

[0049] First, add pure water to the reaction kettle and heat it to 55°C, then add the prepared liquid caustic soda solution to adjust the pH to 12.0, the stirring blade inside the reaction kettle is mixed uniformly at a speed of 450r/min, and the bottom solution of the co-precipitation reaction is prepared. , Then add 1.25mol/L metal salt solution and 9mol/L liquid caustic solution at a flow rate of 60L/h, after 11 hours of co-precipitation in the reactor, flow out from the outlet of the reactor to obtain The solid-liquid mixed amorphous ternary precursor slurry is washed with impurities, filtered, dehydrated, and dried to obtain an amorphous ternary precursor with a composite structure. The amorphous ternary precursor is subjected to high-temperature thermal decomposition treatment at a temperature of 750℃ , The high temperature thermal decomposition treatment time is 22h, the powder material after the high temperature heat treatment is collected, crushed, classified, sieved, and demagnetized to obtain the amorphous single crystal ternary precursor oxide, and then the amorphous single crystal three Lithium carbonate or lithium hydroxide is added to the meta-precursor oxide, and the ternary cathode material is obtained through high-temperature calcination and lithiation treatment.