All-solid-state battery amorphous alloy negative electrode
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
All-solid-state batteries using alloy negative electrode active material particles, such as silicon, suffer from low cycle characteristics due to pulverization and void formation during charging and discharging, leading to increased internal resistance and chemical deterioration.
Innovation Solution
An all-solid-state battery system with a negative electrode active material layer containing alloy particles, where the amorphization degree of the alloy particles is controlled between 27.8% and 82.8%, and a control device regulates the charge-discharge voltage between 2.50 V and 4.40 V, with an initial charging step at a voltage higher than the normal charge-discharge voltage to enhance the amorphous portion and reduce stress on the particles.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Use of energy by moving object
If alloy negative electrode active material particles are used to increase capacity, then energy density is improved, but cycle characteristics deteriorate due to pulverization and void formation
Solution Approach 1:
The patent changes the physical and chemical parameters of the alloy particles by controlling amorphization degree (27.8%-82.8%) and particle size (5 μm or less), and by conducting initial charging at elevated temperatures (40-100°C) to transform the crystalline structure into a more stable amorphous state that reduces expansion stress during cycling
Solution Approach 2:
The patent applies preliminary action by performing an initial charging step before normal battery operation, where the alloy particles are pre-treated at elevated temperatures to induce amorphization and stabilize their structure in advance, preventing pulverization during subsequent charge-discharge cycles
2Use of energy by moving object
If silicon particles are used as alloy negative electrode active material, then capacity is improved, but internal resistance increases due to void formation between particles
Solution Approach 1:
The patent changes the physical parameters of silicon particles by controlling amorphization degree (27.8%-82.8%) and particle size (5 μm or less), transforming them into a stable amorphous structure that maintains intimate contact during cycling, preventing void formation and keeping internal resistance low
Solution Approach 2:
The patent applies preliminary action by performing an initial charging step before normal battery operation, where the silicon particles are pre-treated at elevated temperatures to induce amorphization and stabilize their structure in advance, preventing pulverization during subsequent charge-discharge cycles
3Use of energy by moving object
If alloy negative electrode active material particles are used, then capacity is improved, but chemical deterioration progresses due to expansion and shrinkage during charging and discharging
Solution Approach 1:
The patent changes the physical and chemical parameters of the alloy particles by controlling amorphization degree (27.8%-82.8%) and particle size (5 μm or less), and by conducting initial charging at elevated temperatures (40-100°C) to transform the crystalline structure into a more stable amorphous state that reduces expansion stress during cycling
Solution Approach 2:
The patent applies preliminary action by performing an initial charging step before normal battery operation, where the alloy particles are pre-treated at elevated temperatures to induce amorphization and stabilize their structure in advance, preventing pulverization during subsequent charge-discharge cycles
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 improves the cycle characteristics of the battery by reducing pulverization and chemical deterioration, maintaining a stable structure and enhancing lithium ion storage capacity.
Implementation Method 1
An amorphization degree of the alloy negative electrode active material particles is comprised between 27.8% and 82.8%
Implementation Method 2
alloy negative electrode active material particles are pulverized by expansion and shrinkage during charging and discharging
Data Source
Figure 1~2
Figure 3~4
Figure 5
AI summary
An all-solid-state battery system includes: an all-solid-state battery (6) that includes a positive electrode active material layer, a solid electrolyte layer, and a negative electrode active material layer; and a control device (100) that controls a charge-discharge voltage during use of the all-solid-state battery. The negative electrode active material layer contains alloy negative electrode active material particles. The amorphization degree of the alloy negative electrode active material particles is comprised between 27.8% and 82.8% and satisfies the following conditions 0.32≤Z/W≤0.60, where Z: a controlled discharge capacity (mAh) of the all-solid-state battery, and W: a theoretical capacity (mAh/g) of the alloy negative electrode active material particles×a total weight (g) of the alloy negative electrode active material particles×the amorphization degree (%).