Method for surface modification of lithium cobaltate positive electrode material by phosphorus compound and lithium cobaltate positive electrode material
A cathode material and surface modification technology, applied in battery electrodes, electrochemical generators, structural parts, etc., can solve the problems of difficult regulation and complexity of process control
Active Publication Date: 2022-04-22
NANJING UNIV OF SCI & TECH
View PDF8 Cites 0 Cited by
- Summary
- Abstract
- Description
- Claims
- Application Information
AI Technical Summary
Problems solved by technology
[0004] However, the current process of making the cladding layer is usually very complicated, and it is difficult to control the process control
Method used
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View moreImage
Smart Image Click on the blue labels to locate them in the text.
Smart ImageViewing Examples
Examples
Experimental program
Comparison scheme
Effect test
Embodiment 1
[0052] Mix 0.1g of sodium phosphate and 10g of lithium cobaltate in a ball mill, mill for 2 hours, heat at 400°C in air for 5-6 hours, and cool naturally to obtain a surface-modified lithium cobaltate material.
Embodiment 2
[0054] 0.2 g of sodium hypophosphite and 10 g of lithium cobaltate were ball-milled for 2 hours, heated at 200° C. in argon for 1 hour, and naturally cooled to obtain a surface-modified lithium cobaltate material.
Embodiment 3
[0056] 0.5 g of sodium hypophosphite and 10 g of lithium cobaltate were mixed and ball-milled for 2 hours, heated at 500° C. in air for 2 hours, and naturally cooled to obtain a surface-modified lithium cobaltate material.
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More PUM
| Property | Measurement | Unit |
|---|---|---|
| particle diameter | aaaaa | aaaaa |
Login to View More
Abstract
The invention provides a method for modifying the surface of a lithium cobaltate positive electrode material with a phosphorus-containing compound and the lithium cobaltate positive electrode material, comprising the following steps: step 1, using a layered lithium cobaltate powder material as a matrix, and Compounds are ball milled and mixed according to a certain ratio to obtain a mixed powder material; step 2, heat the mixed powder material in an atmosphere protection environment to obtain a modified lithium cobaltate positive electrode material, the interior of which is lithium cobaltate, and the near surface Including lithium cobalt oxide lattice and phosphate root to form a bond, the surface includes an amorphous coating layer composed of metal ions and phosphate groups. The invention adopts process control and treatment of mixing and heating the phosphorus-containing compound and lithium cobaltate to modify the surface of lithium cobaltate particles, and utilizes the doping of phosphate on the surface lattice to enhance the stability of lithium cobaltate structure ; and effectively protect the electrode electrolyte interface by containing an amorphous coating layer, reduce interface side reactions, and improve rate performance and cycle performance.
Description
technical field [0001] The invention relates to the technical field of lithium cobaltate positive electrode materials, in particular to a method for modifying the surface of lithium cobaltate positive electrode materials with phosphorus compounds and the lithium cobaltate positive electrode materials. Background technique [0002] Lithium cobalt oxide cathode material is an ideal cathode material for lithium-ion batteries in the future. Increasing the working voltage of lithium cobalt oxide can provide higher specific capacity and energy density. However, when the charging voltage reaches 4.5V and above, lithium cobalt oxide faces, such as the irreversibility of the phase transition decreases, the particles undergo c-axis shrinkage greater than 3%, the release of lattice oxygen causes the destruction of the material structure, the phase transition of the interface, A series of problems such as the dissolution of transition metals lead to a decline in its cycle stability. ...
Claims
the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to View More Application Information
Patent Timeline
Login to View More Patent Type & Authority Patents(China)
IPC IPC(8): H01M4/36H01M4/48H01M4/525H01M4/58H01M10/0525
CPCH01M4/366H01M4/5805H01M4/48H01M4/525H01M10/0525Y02E60/10
Inventor 夏晖刘玲郑欣段玉龙薛亮
Owner NANJING UNIV OF SCI & TECH