Electrode Binder Composition for High Peel Strength and Low Resistance

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing electrodes for lithium ion secondary batteries face challenges in achieving high peel strength with reduced binder content, high resistance, and foaming during production, which hinder the demand for smaller, lighter, and faster-charging batteries.

Innovation Solution

A binder for lithium ion secondary batteries comprising a vinyl alcohol polymer and a compound represented by a specific formula, with controlled saponification and modification, is used to enhance peel strength, reduce resistance, and inhibit foaming.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If the amount of binder is reduced to increase energy density, then energy density is improved, but peel strength deteriorates

Engineering Contradiction:

Improveenergy densityVSAvoidpeel strength

Core Design Contradiction:

Quantity of substanceVSStrength

Solution Approach 1:

The patent changes the chemical composition parameters of the binder by incorporating specific polymers (carboxymethyl cellulose, starch, or gelatin) with controlled degrees of substitution or crystallinity. This allows achieving high peel strength with reduced binder content through optimized molecular structure rather than increased quantity.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite binder system by combining multiple components: the specified polymer (carboxymethyl cellulose, starch, or gelatin) with additional additives or modifiers. This composite approach enhances adhesive properties per unit mass, enabling reduced overall binder content while maintaining or improving peel strength.

Inventive Principle:

Principle #40Composite materials

2Ease of manufacture

If mechanical stirring is used to mix electrode slurry, then mixing is achieved, but foaming occurs which reduces manufacturing precision

Engineering Contradiction:

Improvemixing efficiencyVSAvoidslurry uniformity

Core Design Contradiction:

Ease of manufactureVSManufacturing precision

Solution Approach 1:

The patent introduces a defoaming agent as an intermediary substance in the slurry formulation. This agent specifically targets and eliminates foam bubbles generated during mechanical stirring, allowing efficient mixing to continue without the harmful side effect of foaming that would compromise slurry uniformity and electrode quality.

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The patent converts the harmful effect of mechanical stirring (foaming) into a beneficial process by adding defoaming agents that actively seek out and collapse bubbles. The stirring action that creates foam is thus transformed into an effective mixing process, with the defoaming agent converting the harmful foam into harmless dissolved gases or small bubbles that do not affect slurry quality.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

Data Source

PatentUS20260018617A1Binder for electricity storage device, binder solution for electricity storage device, electrode slurry for electricity storage device, electrode for electricity storage device, and electricity storage device

Publication Date: 2026.01.15 KURARAY CO LTD

AI summary

The present disclosure relates to a binder for an electricity storage device comprising a vinyl alcohol polymer.