Non-Aqueous Battery Electrolyte for CNT Anode Storage Stability
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The addition of carbon nanotubes (CNTs) to non-aqueous electrolyte secondary battery negative electrode composite material layers enhances electron conduction but also increases the reaction area, leading to degradation of storage properties due to their large specific surface area, which impairs their function as electron conduction paths and degrades output properties.
Innovation Solution
Incorporating a cationic surfactant with a quaternary ammonium salt in the electrolyte solution that adsorbs on the CNTs, protecting their surface and allowing for effective contact points with the negative electrode active material without inhibiting their formation, thereby reducing storage property degradation and enhancing output properties.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Power
If carbon nanotubes are added to the negative electrode composite material layer to improve electron conduction and output properties, then output properties are improved, but storage properties deteriorate due to increased reaction area
Solution Approach 1:
A cationic surfactant is introduced as an intermediary substance that adsorbs onto the surface of carbon nanotubes. This surfactant layer acts as a mediator that reduces the direct contact between the highly reactive CNT surface and the electrolyte, thereby reducing parasitic reactions and improving storage properties while maintaining the electron conduction function of the CNTs
Solution Approach 2:
The surface properties of carbon nanotubes are modified by changing their chemical state through surfactant adsorption. This parameter change in surface chemistry reduces the specific surface area reactivity of CNTs without significantly affecting their electrical conductivity, thus resolving the contradiction between output and storage properties
2Reliability
If a protective material is mixed with negative electrode active material and CNTs to cover CNTs and reduce reaction area, then storage properties are improved, but contact points between active material and CNTs decrease, impairing electron conduction function
Solution Approach 1:
The cationic surfactant serves as a thin intermediary layer that does not significantly increase the physical distance between active material and CNTs, unlike bulk protective materials. This allows electron conduction pathways to be maintained while still providing surface protection to reduce parasitic reactions
Solution Approach 2:
The protective function is applied locally only at the CNT surface through surfactant adsorption, rather than using a bulk protective material that would uniformly increase distances throughout the electrode structure. This localized protection maintains overall electrode connectivity and electron conduction
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 use of a cationic surfactant with a quaternary ammonium salt in the electrolyte solution effectively reduces storage property degradation while maintaining or improving output properties by ensuring proper contact between CNTs and the negative electrode active material, even with alloy-based materials that undergo significant volume changes during charge and discharge.
Implementation Method 1
The particular surfactant according to the present technique may adsorb on the CNT to protect its surface
Implementation Method 2
The CNTs are expected to form electron conduction paths in the negative electrode composite material layer
Data Source
AI summary
A non-aqueous electrolyte secondary battery includes a positive electrode, a negative electrode, and an electrolyte solution. The negative electrode includes a negative electrode composite material layer. The negative electrode composite material layer includes a negative electrode active material and a carbon nanotube. The electrolyte solution includes a solvent, a supporting electrolyte, and a cationic surfactant. The cationic surfactant includes a quaternary ammonium salt.