Battery Electrode Assembly Segmentation and Heat Pressing

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current methods for manufacturing electrode assemblies for battery cells are inefficient and lack cost-effectiveness, particularly in producing electrode rolls and stacks, with existing bonding methods failing to prevent separator shrinkage during abuse tests.

Innovation Solution

A method involving flat separator sheets and electrode segments with similar longitudinal and lateral extensions, where the segments are alternately arranged and bonded using heat pressing rolls, forming a tape element that is folded to align electrodes in a stacking direction, with an adhesive layer enhancing chemical bonding and mechanical strength.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If conventional bonding methods are used to manufacture electrode assemblies, then production cost and time are reduced, but separator shrinkage occurs during abuse tests compromising safety

Engineering Contradiction:
ImprovesafetyVSAvoidmanufacturing efficiency
Core Design Contradiction:
ReliabilityVSEase of manufacture

Solution Approach 1:

The electrode assembly is divided into multiple unit cells, each with its own separator sheet and electrode segments. This segmentation allows each unit cell to be independently bonded and tested, preventing catastrophic failure across the entire assembly while maintaining production efficiency through modular manufacturing

Inventive Principle:
Principle #1Segmentation

Solution Approach 2:

Adhesive layers are applied to the separator sheets before assembly, and heat pressing is performed during manufacturing to pre-bond the separator sheets to electrode segments. This preliminary bonding prevents separator shrinkage during subsequent abuse tests while maintaining efficient production through integrated processing steps

Inventive Principle:
Principle #10Preliminary action

2Reliability

If electrode segments with similar longitudinal and lateral extensions are used, then packing efficiency and safety are improved, but manufacturing complexity increases

Engineering Contradiction:
ImprovesafetyVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The electrode segments are designed with specific dimensional parameters where the extension in the longitudinal direction is between half and twice the extension in the lateral direction. This parameter optimization improves packing efficiency and safety while the standardized dimensions actually simplify manufacturing by reducing variability

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The separator sheets serve multiple functions: they electrically isolate positive and negative electrodes, provide mechanical support for electrode segments, and act as a bonding substrate for adhesive layers. This multi-functionality reduces the number of separate components needed, simplifying manufacturing despite the specific geometric requirements

Inventive Principle:
Principle #6Universality (Multi-functionality)

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 enables rapid and economical production of electrode assemblies with improved safety by preventing separator shrinkage during tests, combining the advantages of electrode roll and stack production while ensuring mechanical strength and chemical bonding.

Implementation Method 1

bonded using heat pressing rolls

Methodology Applied
Scientific EffectHeat pressing: Heating

Implementation Method 2

adhesive layer enhancing chemical bonding and mechanical strength

Methodology Applied
Scientific EffectChemical bonding: Chemical Bonding

Data Source

PatentEP3557674B1Method for manufacturing an electrode assembly for a battery cell and battery cell
Publication Date: 2023.04.12 GS YUASA INT LTD
  • EP3557674B1 patent drawingFigure 1
  • EP3557674B1 patent drawingFigure 2~3
  • EP3557674B1 patent drawingFigure 4a~4c

AI summary

The invention refers to a method for manufacturing an electrode assembly for a battery cell, whereat segments of a first electrode are placed between a continuous first separator sheet and a continuous second separator sheet; segments of a second electrode are placed on an opposite side of the first separator sheet in respect of the segments of the first electrode and on an opposite side of the second separator sheet in respect of the segments of the first electrode such that a tape element is formed; and the tape element is folded such that the segments of the first electrode and the segments of the second electrode are aligned in a stacking direction. The invention also refers to a battery cell, in particular a lithium ion battery cell, comprising an electrode assembly manufactured using the method according to the invention.