Lithium Ion Battery Electrode Material Conductivity Optimization
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium ion batteries face challenges with electrode materials that have insufficient electron conductivity, leading to issues with high-speed charge and discharge, stability, and safety due to the dissolution of elements like chromium and nickel, which can cause short-circuiting and degrade the negative electrode.
Innovation Solution
An electrode material with a phosphate-based olivine structure, represented by Li x Fe y A z BO 4, is developed, where the particle surfaces are coated with a carbonaceous film, and a small amount of inert nickel is added within a specific concentration range (1 ppm to 100 ppm) to enhance electron conductivity and stability, preventing nickel-induced defects and dissolution.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If elements like chromium and nickel are added to increase electron conductivity, then electron conductivity is improved, but dissolution occurs causing short-circuiting and negative electrode degradation
Solution Approach 1:
The patent resolves this contradiction by changing the concentration parameter of nickel to an optimized range (1 ppm to 100 ppm), which is sufficient to enhance electron conductivity but low enough to prevent harmful dissolution effects. The controlled parameter range ensures nickel remains beneficial without causing short-circuiting or negative electrode degradation.
Solution Approach 2:
The patent applies local quality by introducing nickel in such small, controlled amounts that it locally enhances electron conductivity at critical sites without causing widespread dissolution problems. The localized, controlled addition of nickel achieves conductivity improvement while avoiding the harmful effects of excessive nickel content.
2Productivity
If high current charge and discharge is achieved through miniaturization and conductive substance conjugation, then charge and discharge speed is improved, but manufacturing complexity increases
Solution Approach 1:
The patent simplifies manufacturing by changing the composition parameter approach - instead of requiring miniaturization and complex conjugation processes, it achieves high-speed charge and discharge through optimized nickel content (1 ppm to 100 ppm) in the electrode material itself. This parameter optimization inherently provides the needed conductivity without additional manufacturing complexity.
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
The solution provides improved electron conductivity, load characteristics, and cycle stability, reducing the risk of negative electrode degradation and safety issues, while allowing for high voltage, high energy density, and high-speed charge and discharge capabilities in lithium ion batteries.
Implementation Method 1
the particle surfaces being coated by a carbonaceous material
Implementation Method 2
elements in the electrode material such as chromium and nickel are dissolved in an electrolytic solution during charge and discharge, and are re-precipitated and grow on the negative electrode
Implementation Method 3
elements in the electrode material such as chromium and nickel are dissolved in an electrolytic solution during charge and discharge, and are re-precipitated and grow on the negative electrode
Data Source
AI summary
An electrode material having excellent electron conductivity, load characteristics, and cycle characteristics is provided. The electrode material includes an electrode active material represented by LixFeyAzBO4 (here, A represents either or both selected from a group consisting of Mn and Co, B represents one or more selected from a group consisting of P, Si, and S, 0≤x<4, 0<y<1.5, and 0≤z<1.5) as a main component and nickel, particle surfaces of the electrode active material are coated with a carbonaceous film, and a content of the nickel is in a range of 1 ppm to 100 ppm.