Stacked Electrode Bond Release for Faster Battery Electrolyte Impregnation

Solution Overview

Problem

The increasing volume of stacked electrode bodies in secondary batteries necessitates longer impregnation times for electrolytic solution, leading to extended production lead times and potential increases in production facilities to maintain throughput.

Innovation Solution

A method involving the reduction of adhesive strength between the electrode plate and separator during or after electrolytic solution injection, creating a non-bonded area to facilitate quicker impregnation by allowing the solution to penetrate more easily.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the volume occupied by the stacked electrode body inside the case is increased to increase energy density, then the energy density is improved, but the impregnation time is prolonged

Engineering Contradiction:

Improveenergy densityVSAvoidimpregnation time

Core Design Contradiction:

Quantity of substanceVSLoss of time

Solution Approach 1:

The adhesive layer is designed to automatically reduce its adhesive strength when the electrolytic solution is injected, creating gaps between the electrode plate and separator before the impregnation process begins. This preliminary action facilitates faster electrolytic solution penetration without requiring additional time.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The adhesive layer's adhesive strength is made variable based on temperature changes. When the electrolytic solution is injected, the temperature increases, causing the adhesive strength to decrease and create gaps for solution penetration. This parameter change resolves the contradiction by enabling fast impregnation in larger electrode bodies.

Inventive Principle:

Principle #35Parameter changes

2Reliability

If the impregnation time is extended to ensure complete electrolytic solution penetration, then the solution penetration is improved, but the production lead time is prolonged

Engineering Contradiction:

Improvesolution penetration completenessVSAvoidproduction lead time

Core Design Contradiction:

ReliabilityVSLoss of time

Solution Approach 1:

The adhesive layer is designed to automatically reduce its adhesive strength when the electrolytic solution is injected, creating gaps between the electrode plate and separator before the impregnation process begins. This preliminary action facilitates faster electrolytic solution penetration without requiring additional time.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The adhesive layer transitions from a static bonding state to a dynamic state where adhesive strength decreases in response to temperature changes during electrolytic solution injection. This dynamic behavior ensures complete solution penetration while maintaining short impregnation times.

Inventive Principle:

Principle #15Dynamics

3Productivity

If production facilities are increased to maintain throughput during longer impregnation times, then the throughput is maintained, but the manufacturing complexity and cost increase

Engineering Contradiction:

Improveproduction throughputVSAvoidproduction facilities

Core Design Contradiction:

ProductivityVSDevice complexity

Solution Approach 1:

The adhesive layer is designed to automatically reduce its adhesive strength when the electrolytic solution is injected, creating gaps between the electrode plate and separator before the impregnation process begins. This preliminary action facilitates faster electrolytic solution penetration without requiring additional time.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The adhesive layer self-regulates its adhesive strength in response to temperature changes during the electrolytic solution injection process, automatically creating optimal gaps for solution penetration. This self-service mechanism eliminates the need for external control systems or additional production facilities.

Inventive Principle:

Principle #25Self-service

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 significantly reduces impregnation time, thereby shortening production lead times, avoiding the need for additional facilities, and improving charge-discharge characteristics and cycle life of the battery.

Implementation Method 1

an adhesive layer that has a property of reducing adhesive strength upon heating

Methodology Applied

Scientific EffectThermosensitive adhesive property: Heating

Data Source

PatentUS12620631B2Method for manufacturing battery, and battery

Publication Date: 2026.05.05 PANASONIC HOLDINGS CORP

AI summary

A method for manufacturing a battery includes: accommodating a stacked electrode body, in which a separator that has an adhesive layer and an electrode plate are stacked and the electrode plate is bonded to the separator via the adhesive layer, in a case; injecting an electrolytic solution into the case; and reducing the adhesive strength between the electrode plate and the separator at the same time, or around the same time, as the injection of the electrolytic solution.