Lithium Battery Electrolyte Additives for High-Temp Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Rechargeable lithium batteries with manganese-based active materials experience increased resistance during storage at elevated temperatures, affecting their stability and performance.
Innovation Solution
Incorporating fluoroethylene carbonate, lithium bis(oxalato)borate, and tris(trialkylsilyl)borate additives into the electrolyte, which form a coating layer on the electrodes, reducing resistance and improving charge and discharge efficiency at elevated temperatures.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If manganese-based active material is used to achieve high output, then power is improved, but resistance increases during storage at elevated temperature
Solution Approach 1:
The patent introduces a coating layer as an intermediary substance between the manganese-based active material and the electrolyte. This coating layer, formed by specific additives, mediates the interaction to prevent harmful reactions while allowing beneficial ionic transport, thereby resolving the contradiction between high power output and stability at elevated temperatures
Solution Approach 2:
The patent changes the chemical composition parameters of the electrolyte by adding specific compounds (cyclic carbonate and chain carbonate in optimized ratios). This parameter change modifies the properties of the coating layer formed on the electrode, enabling it to provide both high conductivity for power output and stability at elevated temperatures
2Ease of manufacture
If conventional electrolyte composition is used, then manufacturing simplicity is maintained, but resistance increases during storage at elevated temperature
Solution Approach 1:
The patent creates a composite electrolyte system by combining cyclic carbonate, chain carbonate, and specific additives. This composite material approach maintains ease of manufacture through simple mixing while achieving superior storage stability through the synergistic effects of the components, particularly the formation of a stable coating layer
3Device complexity
If no coating layer is formed, then device complexity is reduced, but resistance increases during storage at elevated temperature
Solution Approach 1:
The patent implements self-service by enabling the electrolyte to automatically form a protective coating layer on the electrode surface during initial charging cycles. This self-forming mechanism eliminates the need for complex external coating processes while providing stable resistance characteristics during storage at elevated temperatures
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 additives significantly decrease resistance and enhance the stability of rechargeable lithium batteries at elevated temperatures, leading to improved storage characteristics and performance.
Implementation Method 1
Incorporating fluoroethylene carbonate, lithium bis(oxalato)borate, and tris(trialkylsilyl)borate additives into the electrolyte, which form a coating layer on the electrodes
Data Source
AI summary
In one aspect, a rechargeable lithium battery including a positive electrode having a positive active material, a negative electrode having a negative active material, and an electrolyte is provided. The positive active material can include manganese-based oxide, and the electrolyte can include fluoroethylene carbonate, lithium bis(oxalato)borate, and tris(trialkylsilyl)borate.