Separator Protrusion for Non-Aqueous Electrolyte Battery
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Conventional non-aqueous electrolyte secondary batteries experience variations in electrode resistance and deteriorated high-rate performance due to dry-up and changes in electrolyte solution concentration, particularly when the excess electrolyte solution is not properly managed during charging and discharging.
Innovation Solution
The battery design includes a stack-type electrode array with separators that project below the electrodes, ensuring the excess electrolyte solution is always in contact with the separators and not with the electrodes, maintaining a specific state of charge range to prevent dry-up and concentration changes, thereby improving resistance against lithium precipitation and high-rate performance.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the excess portion of electrolyte solution is reduced to avoid contact with the electrode, then variation in electrode resistance is suppressed, but the electrolyte solution may dry up or change concentration in the electrode array during high-rate charging and discharging
Solution Approach 1:
The separator acts as an intermediary between the excess electrolyte solution and the electrode. By making the separator protrude, it serves as a mediator that allows the excess electrolyte to be reversibly returned to the electrode array through capillary action without directly contacting the electrode, thus preventing resistance variation while maintaining electrolyte supply
Solution Approach 2:
The solution extends the separator in the vertical dimension beyond the electrode ends, creating a new spatial arrangement. This dimensional change allows the excess electrolyte to be held in a different location (at the protruding separator tip) rather than directly at the electrode surface, resolving the contradiction between preventing contact and maintaining supply
2Quantity of substance
If the excess portion of electrolyte solution is increased to prevent dry-up, then high-rate performance is improved, but the electrode resistance varies due to contact with excess electrolyte
Solution Approach 1:
The electrolyte solution is segmented into two distinct portions: the infiltrated portion within the electrode array and the excess portion held at the protruding separator. This segmentation allows the excess electrolyte to be isolated from direct electrode contact while maintaining its function as a reservoir that can reversibly supply electrolyte during high-rate operation
3Productivity
If the separator is made to protrude below the electrode ends, then the excess electrolyte can be reversibly returned to the electrode array, but the device structure becomes more complex
Solution Approach 1:
The protruding separator performs multiple functions simultaneously: it acts as a physical barrier preventing excess electrolyte contact with the electrode, serves as a reservoir for holding excess electrolyte, and functions as a capillary channel for reversible electrolyte transport. This multi-functionality achieves improved high-rate performance without adding separate components, thus limiting structural complexity
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 configuration effectively suppresses variations in electrode resistance and enhances the battery's high-rate performance by ensuring reversible electrolyte solution distribution and maintaining optimal salt concentration, resulting in improved resistance against lithium precipitation.
Implementation Method 1
the electrolyte solution can reversibly be returned from the excess portion to the electrode array through the separator
Data Source
AI summary
A non-aqueous electrolyte secondary battery includes a housing, a stack-type electrode array accommodated in the housing, and an electrolyte solution. The electrolyte solution includes an infiltrated portion infiltrated into the stack-type electrode array and an excess portion other than the infiltrated portion. In a set-up state that the non-aqueous electrolyte secondary battery is arranged such that a direction of stack of the stack-type electrode array is orthogonal to a vertical direction, a lower end of the separator projects below lower ends of the positive electrode and the negative electrode. In the set-up state, within a range of an operating state of charge, a projecting portion of any of the plurality separators is always in contact with the excess portion and the plurality of positive electrodes and the plurality of negative electrodes are not in contact with the excess portion at any time.