Preparation method of modified lithium battery positive electrode material, modified lithium battery positive electrode material and lithium battery positive electrode structure

[0033] see figure 1 , the first embodiment of the present invention provides a method for preparing a modified lithium battery positive electrode material, comprising the following steps:

[0034] S1. Provide positive electrode precursor material or positive electrode material to be modified;

[0035] S2. Depositing a metal oxide film layer on the surface of the positive electrode precursor material or the positive electrode material to be modified; and

[0036] S3. Calcining the positive electrode precursor material and the lithium source after depositing the metal oxide thin film layer to obtain a modified lithium battery positive electrode material or annealing the positive electrode material after depositing a metal oxide thin film layer to obtain a modified lithium battery positive electrode Material.

[0037] In step S1, in some specific embodiments, the positive electrode material to be modified includes a lithium battery positive electrode material containing manganese

[0096] Embodiment 1 (illustrate by taking the positive electrode material to be modified as lithium manganate particles as an example):

[0097] 1.1. Preparation of lithium manganate particles to be modified:

[0098] Weigh 10g MnCO 3 Put it in a boat-shaped crucible, calcined in a tube furnace, the atmosphere introduced was air, the heating rate was 5°C / min, the calcining temperature was 540°C, and the calcining time was 5h, to obtain Mn 2 o 3 powder, the powder and LiOH·H 2 O was mixed according to the stoichiometric ratio of 1:1, ground evenly in a mortar, then placed in a boat-shaped crucible, and calcined in a tube furnace with oxygen as the atmosphere, the heating rate was 5°C / min, and the calcination temperature was 700° C., calcination time is 20 h, and lithium manganate particles to be modified are obtained.

[0099] 1.2. Coating the surface of the prepared lithium manganate particles to be modified with a metal oxide film layer, the specific steps are as follows

[0119] Embodiment 2: (Illustrate with the lithium manganate precursor material to be modified as an example):

[0120] 2.1. Preparation of lithium manganate precursor particles to be modified:

[0121] Weigh 10gMnCO 3 Put it in a boat-shaped crucible, calcined in a tube furnace, the atmosphere introduced was air, the heating rate was 5°C / min, the calcining temperature was 540°C, and the calcining time was 5h, to obtain Mn 2 o 3 The powder is to obtain the lithium manganate precursor particles to be modified.

[0122] 2.2. Coating the surface of the prepared lithium manganate precursor particles to be modified with a metal oxide film layer, the specific steps are as follows:

[0123] Weigh 10g of the lithium manganate precursor particles to be modified prepared by the aforementioned steps, and place them in the reaction barrel of the atomic layer deposition equipment;

[0124] Evacuate the reaction chamber of the atomic layer deposition equipment to a vacuum range of: 0.05 T