Titanium Composite Electrode Resistance Variation
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium titanium oxide-based negative electrodes in lithium secondary batteries face intrinsic resistance differences due to structural features, leading to varying resistance values and complexity in battery management system prediction algorithms, especially in high-output applications like automotive batteries.
Innovation Solution
A titanium-based composite is developed by doping or coating lithium titanium oxide with specific metal elements like Zr and Nb, and aluminum, optimizing the crystal plane development to achieve consistent resistance values across different SOC settings and charging rates.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Speed
If lithium titanium oxide is used as negative electrode material to achieve high operating voltage and fast charging/discharging, then charging speed and safety are improved, but reversible capacity is reduced and initial efficiency is lowered
Solution Approach 1:
The patent modifies the crystal structure parameters of lithium titanium oxide by controlling particle size (50-200 nm range) and crystal plane orientation ((400) plane development), which changes the material's electrochemical properties to achieve both fast charging capability and improved capacity
2Speed
If lithium titanium oxide particles are miniaturized to enlarge active surfaces and accelerate lithium diffusion, then charging speed is improved, but manufacturing complexity increases
Solution Approach 1:
The patent specifies precise particle size parameters (50-200 nm) and crystal plane ratios ((400)/(111) ≥ 0.76) to optimize lithium diffusion while maintaining manufacturability through controlled synthesis conditions
3Device complexity
If intrinsic resistance differences in lithium titanium oxide are not addressed, then structural simplicity is maintained, but battery management system complexity increases and output characteristics deteriorate
Solution Approach 1:
The patent optimizes crystal plane orientation parameters ((400) plane dominance with ratio ≥ 0.76) to minimize resistance variations during charge/discharge cycles, which simplifies battery management and improves output characteristics
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 titanium-based composite ensures a small resistance change rate, simplifies battery management system prediction algorithms, and enhances output characteristics by maintaining low and consistent resistance values, making it suitable for high-output applications.
Implementation Method 1
a titanium-based composite which is doped with M1 and coated with Al
Implementation Method 2
a titanium-based composite which is doped with M1 and coated with Al
Implementation Method 3
a ratio of a peak area of a plane (400) and a peak area of a plane (111) of 0.76 or more in a measured X-ray diffraction spectrum
Data Source
Figure 1~2
Figure 3
AI summary
The present invention provides a lithium secondary battery, including a positive electrode including a positive electrode active material, a negative electrode including a negative electrode active material, and a separator provided between the positive electrode and the negative electrode, wherein the negative electrode active material may include a titanium-based composite, wherein, when the lithium secondary battery is charged to SOC 50 under C-rate conditions of 0.1 to 40 C, the titanium-based composite has a ratio of the peak area of a plane (400) and the peak area of a plane (111) of 0.76 or more in a measured X-ray diffraction spectrum (XRD). Therefore, the present invention may provide a lithium secondary battery having excellent output characteristics and a battery pack in which a BMS prediction algorithm is simplified.