Coated Active Material With Thin NiO Layer for Lower Battery Resistance
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing method for producing coated active materials using a tumbling fluidized bed granulating-coating machine results in increased battery resistance due to the oxidation of Ni on the surface of active materials, leading to thick NiO layers.
Innovation Solution
A coated active material with a NiO layer of average and maximum thickness of 0.9 nm or less is formed between the active material and the coating layer, using a method that includes forming a slurry liquid droplet and flash drying in a heated gas, thereby suppressing the thickening of the NiO layer.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a coating layer is formed using a tumbling fluidized bed granulating-coating machine by drying while spraying coating liquid, then a coating layer can be formed on the active material surface, but the NiO layer thickness increases due to Ni oxidation in hot and humid conditions, causing battery resistance to increase
Solution Approach 1:
The patent changes the drying parameters by using hot air at 100°C or higher with controlled humidity and extended drying time (30 minutes to 24 hours). This parameter modification prevents excessive Ni oxidation while ensuring complete solvent evaporation, thereby controlling NiO layer thickness to 0.9 nm or less and reducing battery resistance
Solution Approach 2:
The patent applies a preliminary protective coating layer (such as Al2O3, SiO2, or TiO2) on the active material surface before the coating process. This preliminary action creates a barrier that prevents Ni oxidation during subsequent processing, controlling NiO layer formation and maintaining low battery resistance
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
This approach reduces battery resistance by maintaining a thin NiO layer, enhancing the migration of lithium ions and maintaining capacity.
Implementation Method 1
drying while spraying a specific coating liquid on the surface of an active material
Implementation Method 2
drying while spraying a specific coating liquid
Implementation Method 3
Ni being oxidized on the surface of an active material including Ni
Implementation Method 4
flash-drying in a heated gas
Implementation Method 5
flash-drying in a heated gas
Data Source
AI summary
A main object of the present disclosure is to provide a coated active material capable of reducing a battery resistance. The present disclosure achieves the object by providing a coated active material comprising: an active material including Ni, and a coating layer configured to coat at least a part of a surface of the active material, and a NiO layer is formed between the active material and the coating layer, and an average thickness of the NiO layer is 0.9 nm or less.