Lithiated Nickel Oxide Two-Step Calcination for Cycle Stability
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Solution Overview
Problem
Current methods for producing overlithiated lithium-nickel oxides, such as Li2NiO3, are not scalable and face issues with capacity fade in lithium-ion batteries, which affects the battery's lifetime and applicability.
Innovation Solution
A process involving the formation of a particulate hydroxide or oxide of nickel and optional Co and Mn, combined with a source of lithium, followed by thermal treatment at two different temperatures (300-500°C and 500-600°C under oxygen atmospheres) to produce Li1+xTM1-xO2, where x is between 0.05 and 0.33, and TM includes a combination of nickel, cobalt, manganese, and other metals.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If conventional high-temperature calcination (600-1000°C) is used to form lithiated oxide, then the electrode active material is formed through solid-state reaction, but the process suffers from capacity fade and reduced cycle life
Solution Approach 1:
The single high-temperature calcination step (600-1000°C) is divided into two sequential heating zones: a first heating zone at lower temperature (300-500°C) for initial reaction, and a second heating zone at higher temperature (500-600°C) for completing the lithiated oxide formation. This segmentation allows controlled reaction progression, improving cycle life while maintaining material quality.
2Reliability
If single-temperature thermal treatment is used, then the process is simple, but the electrode material shows capacity fade upon multiple cycling
Solution Approach 1:
The thermal treatment process is segmented into two distinct heating zones with different temperature ranges (300-500°C and 500-600°C). The first zone initiates the solid-state reaction between precursor and lithium source, while the second zone completes the formation of lithiated oxide with improved structural stability, thereby enhancing capacity retention upon cycling.
Solution Approach 2:
The first heating zone performs a preliminary thermal treatment at lower temperature to initiate the solid-state reaction and form intermediate products. This preliminary action prepares the material structure for the subsequent second heating zone, which then completes the lithiated oxide formation, resulting in improved capacity retention.
3Productivity
If existing synthesis methods for Li2NiO3 are used, then the material can be produced, but the processes are not scalable for industrial production
Solution Approach 1:
The manufacturing process is segmented into distinct operational stages corresponding to the two heating zones, with the first zone (300-500°C) handling initial reaction and the second zone (500-600°C) handling final material formation. This segmentation enables modular reactor design and controlled material flow, significantly improving scalability for industrial production while maintaining manufacturing control.
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 process enables the scalable production of electrode active materials with improved stability and performance upon multiple cycling, developing an electrochemically active rock-salt structure that enhances the battery's capacity retention.
Implementation Method 1
During the thermal treatment, a solid-state reaction takes place, and the electrode active material is formed
Implementation Method 2
The thermal treatment is performed in the heating zone of an oven or kiln... the mixture is first preheated at 400°C to 600° and then heated at 680°C to 780°C
Data Source
Figure 1
AI summary
Process for making a lithiated oxide, said process comprising the following steps:(a) making a particulate hydroxide, oxide or oxyhydroxide of nickel, and, optionally, at least one of Co and Mn and, by combining an aqueous solution of sodium or potassium hydrox-ide with an aqueous solution containing a water-soluble salt of nickel and, optionally, awater-soluble salt of Co, Mn, Al, Ti, Zr, W, Mo, Ga, Nb, Ta, or Mg,(b) adding a source of lithium,(c) treating the mixture obtained from step (b) thermally at at least two different temperatures:(c1) at 300 to 500°C under an atmosphere that may comprise oxygen,(c2) at 500 to 600°C under an atmosphere of oxygen,wherein the temperature in step (c2) is set to be higher than in step (c1).