Composite Transition Metal Oxide Precursor for High-Yield Cathode Synthesis
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The existing methods for synthesizing cathode active materials for lithium secondary batteries face challenges such as low productivity and economic efficiency due to the use of hydroxide-based precursors, which are metastable and react with moisture, leading to surface reactions and difficulties in optimizing the molar ratio, resulting in suboptimal capacity and lifespan characteristics.
Innovation Solution
A composite transition metal oxide-based precursor is developed by oxidizing a hydroxide-based precursor under an oxygen atmosphere or using an oxidizing agent, enhancing the oxygen fraction and improving the synthesis yield, which is then used to create a high-Ni-based cathode active material with optimized molar ratios and improved stability.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Productivity
If hydroxide-based precursor is used for synthesizing cathode active material, then the synthesis process can be carried out, but the production yield is low (approximately 70%) and productivity deteriorates
Solution Approach 1:
The patent changes the chemical composition parameter of the precursor by incorporating oxygen into the hydroxide-based precursor to form a composite structure (Ni1-x-yCoxMn yOz where z≥1.95). This parameter change transforms the precursor from a simple hydroxide to a composite oxide-hydroxide structure, which improves both the stability and the reaction yield during cathode active material synthesis
Solution Approach 2:
The patent creates a composite precursor material combining oxide and hydroxide phases (Ni1-x-yCoxMn yOz with z≥1.95). This composite structure leverages the advantages of both oxide (stability) and hydroxide (reactivity), resolving the contradiction between precursor stability and production yield by integrating both phases in a single precursor formulation
2Ease of manufacture
If hydroxide-based precursor is used, then the synthesis can proceed, but the precursor is metastable in air and reacts with moisture causing surface reactions
Solution Approach 1:
The patent applies preliminary anti-action by pre-incorporating oxygen into the hydroxide-based precursor to form a composite structure before the actual synthesis. This preliminary modification creates a more stable precursor that resists moisture reaction, preventing the harmful surface reactions that would otherwise occur during storage and handling in air
Solution Approach 2:
By changing the oxygen content parameter (z≥1.95 in Ni1-x-yCoxMn yOz), the patent transforms the precursor from a moisture-sensitive hydroxide to a more stable composite oxide-hydroxide structure, improving ease of storage and handling while maintaining manufacturability
3Manufacturing precision
If hydroxide-based precursor is used, then the synthesis process can be completed, but it is difficult to optimize the molar ratio in the reaction with lithium
Solution Approach 1:
The patent changes the stoichiometric parameters of the precursor by incorporating excess oxygen (z≥1.95), which compensates for oxygen loss during the high-temperature synthesis reaction. This parameter adjustment allows for better control and optimization of the molar ratio between transition metals and lithium, improving both manufacturing precision and reaction yield
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 significantly enhances the initial discharge capacity and lifespan characteristics of lithium secondary batteries while increasing productivity and reducing byproduct water production, making the cathode active material more stable and cost-effective.
Implementation Method 1
oxidizing a hydroxide-based precursor under an oxygen atmosphere or using an oxidizing agent
Implementation Method 2
performing a heat treatment on a hydroxide-based composite transition metal precursor in the related art under the oxygen atmosphere
Data Source
AI summary
The present disclosure provides a novel composite transition metal oxide-based precursor, a preparing method thereof, and a cathode active material for a secondary battery prepared from the precursor. In the present disclosure, it is possible to enhance productivity and economic efficiency due to a high reaction yield during the synthesis of a cathode active material and to enhance the initial discharge capacity and lifespan characteristics of a secondary battery including a cathode active material by using an oxide-based precursor having a high oxygen fraction instead of a hydroxide-based precursor used as a precursor of a cathode active material in the related art.