Stacked Graphite Negative Electrode for Li-Ion Battery Energy Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Lithium-ion batteries face a trade-off between increasing energy density and maintaining charging speed, as higher capacity density in the negative electrode leads to longer charging times, which is not suitable for miniaturized and long-standing terminal devices.
Innovation Solution
A negative electrode for lithium-ion batteries is designed with at least two graphite layers of different capacity densities stacked on a current collector, allowing for an increased average capacity density without extending charging time, thereby enhancing energy density and reducing battery volume.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If the capacity density of the negative electrode is increased to improve energy density, then the energy density of the lithium-ion battery is improved, but the charging time is extended
Solution Approach 1:
The negative electrode is segmented into multiple graphite layers with different capacity densities. The patent divides the graphite material into at least two layers, where the first graphite layer has a different capacity density than the second graphite layer. This segmentation allows different regions of the electrode to serve different functions: some layers optimized for high capacity storage while others facilitate faster charging kinetics, thereby resolving the contradiction between energy density and charging time.
Solution Approach 2:
Different regions of the negative electrode are assigned different local properties through varying capacity densities in different graphite layers. The patent specifies that the first graphite layer and second graphite layer have different capacity densities, creating local quality variations that optimize both energy storage (in high-capacity-density regions) and charging speed (in low-capacity-density regions), thus simultaneously improving energy density while maintaining acceptable charging times.
2Use of energy by moving object
If the capacity density of the negative electrode is increased, then the energy density is improved, but the volume of the battery must be reduced for miniaturized devices
Solution Approach 1:
The negative electrode is segmented into multiple graphite layers with different capacity densities. The patent divides the graphite material into at least two layers, where the first graphite layer has a different capacity density than the second graphite layer. This segmentation allows different regions of the electrode to serve different functions: some layers optimized for high capacity storage while others facilitate faster charging kinetics, thereby resolving the contradiction between energy density and charging time.
Solution Approach 2:
Different regions of the negative electrode are assigned different local properties through varying capacity densities in different graphite layers. The patent specifies that the first graphite layer and second graphite layer have different capacity densities, creating local quality variations that optimize both energy storage (in high-capacity-density regions) and charging speed (in low-capacity-density regions), thus simultaneously improving energy density while maintaining acceptable charging times.
Data Source
Figure 1
Figure 2
Figure 3
AI summary
The disclosure provides a negative electrode for a lithium-ion battery of a terminal device. The negative electrode for the lithium-ion battery includes a current collector (210) and at least two graphite layers (220). The at least two graphite layers (220) with different capacity densities cover a surface of the current collector (210) in a stacked manner. For the lithium-ion battery including the negative electrode for the lithium-ion battery and the terminal device, when charging time is ensured, the capacity density is improved, an energy density of the lithium-ion battery is improved, and the volume of the lithium-ion battery is reduced.