Solid Electrolyte Conductivity at 90°C via Polyvalent Substitution

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium ion batteries require a solid electrolyte with high conductivity at elevated temperatures, such as 90°C, to meet the demands of applications in high-temperature conditions while maintaining stability and performance.

Innovation Solution

A solid electrolyte comprising compounds where a part of the Li atom is substituted with polyvalent atoms from Group 2, 3, 12, or 13 elements, specifically Ca, Sr, Ba, Zn, Y, or Al, which exhibit high ionic conductivity at 90°C, enabling efficient lithium ion conduction through mechanisms like hopping conduction.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a conventional solid electrolyte is used, then stability is maintained, but lithium ion conductivity at high temperature (90°C) is insufficient

Engineering Contradiction:

ImprovestabilityVSAvoidlithium ion conductivity

Core Design Contradiction:

ReliabilityVSPower

Solution Approach 1:

The patent changes the chemical composition parameters of the solid electrolyte by substituting Li atoms with polyvalent atoms (Mg, Ca, Sr, Ba, Zn, Al) in specific ratios. This compositional parameter change enables the electrolyte to achieve high lithium ion conductivity at 90°C while maintaining stability, resolving the contradiction between stability and conductivity power.

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite solid electrolyte material by combining multiple elements (Li, P, S, and polyvalent atoms) in a specific compound structure. This composite approach allows the material to exhibit both stability and high conductivity properties that individual components cannot achieve alone, particularly at elevated temperatures.

Inventive Principle:

Principle #40Composite materials

2Power

If lithium ion conductivity is increased through composition modification, then high temperature performance improves, but manufacturing complexity increases

Engineering Contradiction:

Improvelithium ion conductivityVSAvoidmanufacturing complexity

Core Design Contradiction:

PowerVSEase of manufacture

Solution Approach 1:

The patent defines specific compositional parameter ranges (substitution ratios of polyvalent atoms) that optimize conductivity while maintaining manufacturability. By establishing clear parameter boundaries, the invention balances performance improvement with manufacturing ease, avoiding excessive complexity.

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 solid electrolyte achieves high lithium ion conductivity and excellent battery performance at temperatures of 50°C or higher, making it suitable for various applications including electric vehicles and portable devices.

Implementation Method 1

enabling efficient lithium ion conduction through mechanisms like hopping conduction

Methodology Applied

Scientific EffectHopping conduction:

Data Source

PatentUS20220173430A1Solid electrolyte, electrode for lithium ion battery, and lithium ion battery

Publication Date: 2022.06.02 TOYOTA JIDOSHA KK

AI summary

The solid electrolyte of the present disclosure includes at least one compound selected from a group including (A) a compound in which a part of Li atom in Li3PS4 is substituted with a polyvalent atom (provided that Mg is excluded); (B) a compound in which a part of Li atom in Li6PS5X (X: Cl, Br or I) is substituted with a polyvalent atom; and (C) a compound in which a part of Li atom in Li7P3S11 is substituted with a polyvalent atom.