Energy Storage Separator Asymmetry for Electrolyte Penetration

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

The manufacturing time of energy storage devices is prolonged due to inefficient electrolyte penetration into the positive composite layer during the manufacturing process, particularly because the insulating layer on the separator absorbs and holds electrolyte, hindering its distribution.

Innovation Solution

The energy storage device design includes a separator with an insulating layer on its surface opposing the positive electrode, where the negative and positive composite layer non-forming parts are disposed in opposite directions, and the distance from the end of the positive composite layer to the separator is shorter than from the end of the negative composite layer to the separator, facilitating efficient electrolyte penetration by optimizing the flow routes and reducing absorption delays.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a separator with an insulating layer is used to prevent short circuit, then safety is improved, but electrolyte penetration into the positive composite layer becomes inefficient, prolonging manufacturing time

Engineering Contradiction:
Improveshort circuit preventionVSAvoidmanufacturing time
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent applies asymmetry by creating unequal distances from the separator to the positive and negative electrodes. Specifically, the distance from the separator to the positive electrode is made smaller than the distance to the negative electrode, which compensates for the electrolyte absorption by the insulating layer and ensures efficient electrolyte distribution to both electrodes while maintaining short circuit prevention.

Inventive Principle:
Principle #4Asymmetry

Solution Approach 2:

The patent changes the geometric parameters of the battery structure, specifically the distances W1 and W2 from the separator to each electrode. By optimizing these parameters (making W1 < W2), the patent achieves balanced electrolyte distribution despite the presence of the insulating layer, thus resolving the contradiction between safety and manufacturing efficiency.

Inventive Principle:
Principle #35Parameter changes

2Reliability

If the separator is disposed to project beyond electrode ends to prevent short circuit from heat contraction, then reliability is improved, but the distance for electrolyte penetration increases, worsening productivity

Engineering Contradiction:
Improveshort circuit prevention from heat contractionVSAvoidelectrolyte penetration time
Core Design Contradiction:
ReliabilityVSProductivity

Solution Approach 1:

The patent uses asymmetric positioning of the separator relative to the positive and negative electrodes. The separator projects beyond the positive electrode end by a smaller amount than beyond the negative electrode end, creating different penetration distances (W1 < W2) that optimize electrolyte distribution while maintaining adequate projection for thermal contraction protection.

Inventive Principle:
Principle #4Asymmetry

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 design significantly shortens the manufacturing time by ensuring the electrolyte efficiently penetrates into the positive composite layer, enhancing the energy storage device's production efficiency and preventing incomplete charge-discharge reactions.

Implementation Method 1

the insulating layer on the separator absorbs and holds electrolyte, hindering its distribution

Methodology Applied
Scientific EffectAbsorption: Absorption (physical)

Data Source

PatentEP3361547B1Power storage element
Publication Date: 2022.01.26 GS YUASA INT LTD
  • EP3361547B1 patent drawingFigure 1~2
  • EP3361547B1 patent drawingFigure 3~4
  • EP3361547B1 patent drawingFigure 5

AI summary

An object of the invention is to shorten the manufacturing time of an energy storage device by causing electrolyte to efficiently penetrate into a positive composite layer in a process of injecting the electrolyte. An energy storage device in which a negative electrode having a negative composite layer on a negative electrode collector foil and a negative composite layer non-forming part along a side of a negative electrode collector foil, and a positive electrode having a positive composite layer on a positive electrode collector foil and a positive composite layer non-forming part along a side of the positive electrode collector foil are laminated with a separator interposed therebetween, the separator having an insulating layer on its surface opposing the positive electrode, the negative composite layer non-forming part and the positive composite layer non-forming part are disposed in opposite directions to each other, a part of the negative composite layer non-forming part is connected to a negative electrode current collector, and a part of the positive composite layer non-forming part is connected to a positive electrode current collector. An end S1 on a side of the negative electrode current collector of the separator is projected more than an end P1 on the side of the negative electrode current collector of the positive composite layer, an end S2 on a side of the positive electrode current collector of the separator is projected more than an end P2 on the side of the positive electrode current collector of the positive composite layer, and a distance W2 from the end P2 of the positive composite layer to the end S2 of the separator is smaller than a distance W1 from the end P1 of the positive composite layer to the end S1 of the separator. This makes it possible to shorten the manufacturing time of the energy storage device.