Electrode Assembly Tab Layout for Lower Resistance and Capacity Loss
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Existing electrode assemblies in secondary batteries face challenges with high resistance and capacity loss, which affect the performance and efficiency of lithium ion secondary batteries.
Innovation Solution
The electrode assembly design includes a positive electrode sheet and a negative electrode sheet with specific non-coating portions and tabs, along with a separator, where the number of negative electrode tabs is increased to reduce resistance and the positioning of tabs is optimized to minimize capacity loss by preventing overlapping during winding.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If the number of electrode tabs is increased, then resistance is reduced, but device complexity increases
Solution Approach 1:
The electrode sheets are divided into multiple non-coating portions, with tabs positioned at different locations. This segmentation allows current to be collected from multiple points simultaneously, reducing overall resistance without requiring a single complex tab structure
Solution Approach 2:
Different regions of the electrode sheets are assigned different functions: active material portions for energy storage and non-coating portions for current collection. This local differentiation optimizes both electrical conductivity and energy capacity, reducing resistance while maintaining structural simplicity
2Loss of energy
If tabs are positioned to prevent overlapping during winding, then capacity loss is minimized, but manufacturing precision requirements increase
Solution Approach 1:
Multiple non-coating portions are distributed at different locations on the electrode sheets. This segmentation ensures that during the winding process, the tabs from different portions naturally separate and do not overlap, minimizing capacity loss while using a straightforward manufacturing approach
Solution Approach 2:
The non-coating portions and tabs are pre-positioned on the electrode sheets before the winding process. This preliminary arrangement ensures that when winding occurs, the tabs are already in optimal positions to prevent overlapping, reducing the need for high-precision control during the winding operation itself
Data Source
AI summary
An electrode assembly including a positive electrode sheet having a positive electrode active material portion that is an area on which a positive electrode active material is stacked on a positive electrode collector and a positive electrode non-coating portion, a positive electrode tab disposed on the positive electrode non-coating portion, a negative electrode sheet having a negative electrode active material portion that is an area on which a negative electrode active material is stacked on a negative electrode collector and a negative electrode non-coating portion; a negative electrode tab disposed on the negative electrode non-coating portion, and a separator insulating the positive electrode sheet and the negative electrode sheet from each other is provided. The positive electrode non-coating portion includes a first positive electrode non-coating portion and a second positive electrode non-coating portion, which are provided on two portions spaced apart from each other on the positive electrode sheet.