Resin Current Collector with Concavoconvex Shape for Battery Electrodes

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The use of a resin current collector in electrodes leads to increased contact resistance between the resin current collector and the electrode, which hinders the efficiency of energy transfer in batteries.

Innovation Solution

An electrode design featuring a resin current collector with a conductive filler and an active material layer, where the active material layer is disposed between the resin current collector and the electrolyte layer, and the resin current collector has a concavoconvex shape that matches the shape of the active material layer, with a conductive member extending beyond the surface of the resin current collector to enhance electrical contact.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Weight of moving object

If a resin current collector is used, then weight reduction and flexibility are improved, but contact resistance between the current collector and electrode increases

Engineering Contradiction:

Improveweight of current collectorVSAvoidcontact resistance

Core Design Contradiction:

Weight of moving objectVSReliability

Solution Approach 1:

The current collector is constructed as a composite material combining resin (for weight reduction and flexibility) with conductive filler particles (for electrical conductivity). This composite structure allows the current collector to maintain the lightweight advantages of resin while compensating for its poor conductivity through the distributed conductive network formed by the filler particles.

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The surface of the current collector is given a specific concavoconvex shape that locally matches the electrode surface topology. This local geometric adaptation increases the contact area between the current collector and electrode at their interface, thereby reducing contact resistance in the critical contact regions without compromising the overall lightweight composite structure.

Inventive Principle:

Principle #3Local quality

2Ease of manufacture

If the current collector surface is made flat, then manufacturing simplicity is maintained, but contact area with electrode is reduced

Engineering Contradiction:

Improvemanufacturing simplicityVSAvoidcontact area

Core Design Contradiction:

Ease of manufactureVSArea of stationary object

Solution Approach 1:

The concavoconvex shape is pre-formed on the current collector surface during the manufacturing process, before electrode assembly. This preliminary shaping ensures that when the electrode is placed on the current collector, the surfaces naturally conform to each other, maximizing contact area without requiring complex post-assembly adjustments or procedures.

Inventive Principle:

Principle #10Preliminary action

Solution Approach 2:

The current collector surface features concavoconvex curved structures rather than a flat surface. These curved geometric features are designed to conform to the electrode surface, creating multiple contact points and increasing the overall contact area, which reduces contact resistance between the two components.

Inventive Principle:

Principle #14Spheroidality (Curvature)

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 configuration reduces contact resistance and improves electron conductivity, leading to enhanced battery performance and durability by ensuring better contact between the conductive filler and the conductive member.

Implementation Method 1

a resin current collector containing a polymer material and a conductive filler

Methodology Applied

Scientific EffectElectron conduction: Conduction (electrical)

Implementation Method 2

pressing a mold having a surface shape of the convex shape or the concavoconvex shape against the coating film of the resin current collector to perform hot pressing

Methodology Applied

Scientific EffectThermal conduction and melting: Conduction (thermal)

Data Source

PatentEP3367476B1Electrode and manufacturing method therefor

Publication Date: 2020.12.16 NISSAN MOTOR CO LTD

Figure 1~3
Figure 4A~4B
Figure 4C~4D

AI summary

The present invention provides an electrode capable of reducing contact resistance between a resin current collector and the electrode, and a method of manufacturing the electrode. The electrode of the present invention includes a positive electrode current collector 11 containing a polymer material and a conductive filler, a positive electrode active material layer 13 disposed adjacent to the positive electrode current collector, and a concavoconvex shape 11c corresponding to a concavoconvex shape 13c formed on a surface of the positive electrode active material layer that is in contact with the positive electrode current collector, the concavoconvex shape being formed on a surface of the positive electrode current collector that is in contact with the positive electrode active material layer. In the concavoconvex shape in the positive electrode current collector, at least a part of the positive electrode conductive member 14 that is in electrical contact with the conductive filler exists in the positive electrode current collector beyond the surface of the positive electrode current collector.