Electrode Resistance Layer Coating to Prevent Battery Overhang Shorts
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
During the manufacturing of electrode assemblies for secondary batteries, overhangs can occur, leading to direct contact between positive and negative electrodes, which may result in short circuits and reduced battery safety.
Innovation Solution
A manufacturing method for electrodes that involves forming resistance layers with inorganic additives and a binder at opposite ends of the electrode active material layer, using a slot die with two discharge ports to apply the electrode slurry and resistance layer composition simultaneously, and notching the current collector to form an electrode tab at one end.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If resistance layers are formed at opposite ends of the electrode active material layer to prevent short circuits, then battery safety is improved, but device complexity increases
Solution Approach 1:
The electrode is segmented into three distinct regions: a central electrode active material layer for electrochemical reactions, and resistance layers at both opposite ends to prevent short circuits. This segmentation allows the electrode to simultaneously achieve safety (through resistance layers) and functionality (through the active material layer), resolving the contradiction between reliability and structural complexity by organizing components into functional segments.
Solution Approach 2:
Different regions of the electrode are assigned different properties: the central region contains electrode active material for electrochemical activity, while the end regions contain resistance layers with high electrical resistance to prevent short circuits. This local differentiation of material properties allows the electrode to provide both safety functions at the ends and electrochemical functionality in the center, resolving the contradiction between reliability improvement and overall device complexity.
2Productivity
If a single slot die with two discharge ports is used to apply electrode slurry and resistance layer composition simultaneously, then productivity is improved, but manufacturing precision requirements increase
Solution Approach 1:
Two separate coating operations (applying electrode slurry and applying resistance layer composition) are merged into a single slot die unit with two discharge ports. This consolidation allows simultaneous deposition of both layers in one pass, significantly improving productivity by eliminating sequential processing steps and reducing equipment complexity, while the coordinated discharge ports maintain precise layer placement.
Solution Approach 2:
The slot die is designed with multi-functionality, serving both to apply the electrode slurry and to apply the resistance layer composition through its two discharge ports. This universal tool replaces what would traditionally require separate coating devices, improving productivity while the precise positioning of the two discharge ports ensures that manufacturing precision requirements are met through integrated design.
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 method enhances battery safety by preventing short circuits due to overhangs and improves productivity by streamlining the application process using a single slot die with two discharge ports.
Implementation Method 1
the step of forming the electrode active material layer and resistance layer is performed by one slot die in which two discharge ports are formed
Implementation Method 2
a step of drying of the current collector in which the electrode active material layer and resistance layer are formed
Data Source
Figure 1
Figure 2(a)~2(b)
Figure 3
AI summary
The present invention relates to a manufacturing method of an electrode, wherein productivity is improved by preventing a short circuit forming between a positive electrode and negative electrode even when an overhang occurs during manufacture of an electrode assembly. The present invention includes a step of forming an electrode active material layer and a resistance layer, by applying a resistance layer composition including inorganic additives and an electrode slurry, including an electrode active material on a current collector; a step of drying the current collector in which the electrode active material layer and resistance layer are formed; and a step of forming the electrode in which an electrode tab is formed at one end by notching the dried current collector and the step of forming the electrode active material layer and resistance layer is performed by one slot die in which two discharge ports are formed.