All-Solid Battery Positive Electrode Material

Solution Overview

Problem

All-solid state secondary batteries using organic macromolecules as solid electrolytes face issues with excessive coating formation, impairing ion conductivity and degrading discharge capacity and output characteristics.

Innovation Solution

A positive electrode material comprising a metal Group I or II inorganic solid electrolyte, an auxiliary conductive agent, and a dispersant with specific functional groups, which enhances dispersion stability and interface formation, leading to improved discharge capacity and output characteristics.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Ease of manufacture

If an organic macromolecule such as polyethylene oxide is used as the solid electrolyte and binder, then the battery structure can be simplified and manufactured, but excessive coating formation occurs on the active material or solid electrolyte particles, impairing ion conductivity and degrading discharge capacity and output characteristics

Engineering Contradiction:

Improveease of manufactureVSAvoiddischarge capacity

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent extracts and removes the organic macromolecule binder from the electrode composition, replacing it with an inorganic solid electrolyte that serves both as electrolyte and binding function. This eliminates the harmful coating effect while maintaining structural integrity and ion conductivity.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The inorganic solid electrolyte particles perform multiple functions simultaneously: they serve as the electrolyte for ion conduction, as a binder to hold the active material particles together, and as a protective layer. This multi-functionality eliminates the need for separate organic binder materials.

Inventive Principle:

Principle #6Universality (Multi-functionality)

2Ease of manufacture

If an organic macromolecule such as polyethylene oxide is used as the solid electrolyte and binder, then the battery structure can be simplified and manufactured, but excessive coating formation occurs on the active material or solid electrolyte particles, impairing ion conductivity

Engineering Contradiction:

Improveease of manufactureVSAvoidion conductivity

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent extracts and removes the organic macromolecule binder from the electrode composition, replacing it with an inorganic solid electrolyte that serves both as electrolyte and binding function. This eliminates the harmful coating effect while maintaining structural integrity and ion conductivity.

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The patent changes the material parameter from organic macromolecule to inorganic solid electrolyte, fundamentally altering the chemical and physical properties of the binder. This parameter change eliminates the coating formation issue while maintaining or improving ion conductivity.

Inventive Principle:

Principle #35Parameter changes

3Quantity of substance

If electrodes and electrolytes are directly arranged in series to increase energy density, then the energy density can be significantly increased, but the compatibility with positive electrode materials capable of increasing potentials must be ensured

Engineering Contradiction:

Improveenergy densityVSAvoidcompatibility

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The patent changes the electrolyte material parameter from organic to inorganic solid electrolyte, which enables higher operating potentials. This parameter change allows the use of high-potential positive electrode materials while maintaining stability and compatibility in the stacked electrode configuration.

Inventive Principle:

Principle #35Parameter changes

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

The proposed material achieves favorable discharge capacity and output characteristics in all-solid state secondary batteries by forming stable interfaces among solid particles, thereby improving battery performance.

Implementation Method 1

an inorganic solid electrolyte having conductivity of ions of metals belonging to Group I or II of the periodic table

Methodology Applied

Scientific EffectIon conduction: Conduction (electrical)

Implementation Method 2

a dispersant including a compound having at least one selected from a group of functional groups

Methodology Applied

Scientific EffectAdsorption: Adsorption

Data Source

PatentUS10424778B2Material for positive electrode, electrode sheet for all-solid state secondary battery, all-solid state secondary battery, and methods for manufacturing electrode sheet for all-solid state secondary battery and all-solid state secondary battery

Publication Date: 2019.09.24 FUJIFILM CORP

AI summary

A material for a positive electrode containing: a positive electrode active material, an inorganic solid electrolyte having conductivity of ions of metals belonging to Group I or II of the periodic table; an auxiliary conductive agent; and a dispersant including a compound having at least one selected from a group of functional groups (I), an electrode sheet for an all-solid state secondary battery and an all-solid state secondary battery for which the material for a positive electrode is used, and methods for manufacturing an electrode sheet for an all-solid state secondary battery and an all-solid state secondary battery. Group of functional groups (I): acidic groups, (meth)acryloyl groups, (meth)acryloyloxy groups, (meth)acrylamide groups, alkoxysilyl groups, epoxy groups, oxetanyl groups, isocyanate groups, cyano groups, and mercapto groups.