Tapered Solid-State Battery Electrodes to Prevent Interface Cracking

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Solid-state batteries face issues with cracking and peeling at the boundary between the electrode and electrolyte regions due to differences in thermal and mechanical properties, leading to deterioration of battery performance.

Innovation Solution

The solid-state battery features a layered body with a positive electrode layer, a negative electrode layer, and a solid electrolyte, where at least one electrode layer has a tapered shape towards its edge in a sectional view, forming an integrally sintered body with the electrolyte to enhance structural integrity.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If the electrode region and electrolyte region are composed of materials with significantly different thermal and mechanical properties, then the battery can achieve proper functional separation, but stress generated during production or use causes cracking or peeling at the boundary portion

Engineering Contradiction:

Improvebattery performance stabilityVSAvoidboundary portion strength

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The patent applies local quality by creating a boundary portion with a gradual transition in material composition and density between the electrode region and electrolyte region. This gradient structure allows the boundary to have intermediate properties that bridge the significant differences between the two regions, reducing thermal and mechanical property mismatches locally at the interface while maintaining proper functional separation in the bulk materials.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs parameter changes by controlling the density and composition gradient in the boundary portion. By varying the density parameter continuously from the electrode side to the electrolyte side, the patent reduces abrupt changes in thermal and mechanical properties, thereby minimizing stress concentration and preventing cracking or peeling at the boundary during production and use.

Inventive Principle:

Principle #35Parameter changes

2Ease of manufacture

If the boundary portion between electrode region and electrolyte region has a drastic change in material proportion, then the structure is simple to manufacture, but stress causes cracking or peeling during production or use

Engineering Contradiction:

Improveboundary structure fabricationVSAvoidcracking and peeling resistance

Core Design Contradiction:

Ease of manufactureVSReliability

Solution Approach 1:

The patent uses parameter changes by implementing a continuous density gradient in the boundary portion rather than an abrupt transition. This gradient structure, where density varies continuously from the electrode side to the electrolyte side, reduces stress concentration while remaining compatible with conventional manufacturing processes like sintering, thus maintaining ease of manufacture while significantly improving cracking and peeling resistance.

Inventive Principle:

Principle #35Parameter changes

3Area of stationary object

If the electrode layer has a tapered shape toward the edge, then the contact area between electrode and electrolyte regions increases, but the manufacturing precision requirement increases

Engineering Contradiction:

Improvecontact area between electrode and electrolyteVSAvoidtapered shape fabrication precision

Core Design Contradiction:

Area of stationary objectVSManufacturing precision

Solution Approach 1:

The patent applies parameter changes by creating a gradual density gradient that naturally forms a tapered shape in the electrode layer toward the edge. This density transition, rather than a sharp geometric feature, achieves increased contact area between electrode and electrolyte regions while being more tolerant to manufacturing variations, thus reducing the stringency of manufacturing precision requirements.

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

This configuration reduces stress concentrations and increases the contact area between the electrode and electrolyte regions, thereby preventing cracking and peeling, and improving the long-term reliability and performance of the solid-state battery.

Implementation Method 1

a solid-state battery including a solid-state battery layered body including a positive electrode layer, a negative electrode layer, and a solid electrolyte interposed between the positive electrode layer and the negative electrode layer

Methodology Applied

Scientific EffectIonic conduction: Conduction (electrical)

Implementation Method 2

the positive electrode layer, the negative electrode layer, and the solid electrolyte are an integrally sintered body

Methodology Applied

Scientific EffectSintering: Sintering

Data Source

PatentUS12283659B2Solid-state battery

Publication Date: 2025.04.22 MURATA MFG CO LTD

AI summary

A solid-state battery that includes a solid-state battery layered body including a positive electrode layer, a negative electrode layer, and a solid electrolyte interposed between the positive electrode layer and the negative electrode layer, wherein at least one electrode layer of the positive electrode layer and the negative electrode layer has a tapered shape toward an edge of the electrode layer in a sectional view thereof, and the positive electrode layer, the negative electrode layer, and the solid electrolyte are an integrally sintered body.