Solid-State Battery Pressing to Prevent Electrolyte Layer Penetration
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
The production of all solid-state batteries faces challenges with secondary particles from active material layers entering or penetrating through the solid electrolyte layer, leading to short circuits between the cathode and anode during the stacking process.
Innovation Solution
A method involving the crushing of secondary particles to primary particles at the interfacial portion between the active material layer and the solid electrolyte layer during the pressing step, ensuring the primary particles are small enough not to penetrate the electrolyte layer, with a diameter ratio of primary particles to solid electrolyte thickness maintained at 0<(X/Y)≤0.1.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If secondary particles of active material are contained in the active material layer, then the interfacial resistance is reduced and discharge capacity is improved, but the secondary particles may enter into or penetrate through the solid electrolyte layer causing short circuits
Solution Approach 1:
The secondary particles are pre-formed and positioned in the active material layer before assembly, allowing their beneficial electrical contact properties to be established in advance while controlling their size and distribution to prevent penetration
Solution Approach 2:
The particle size parameter of the active material is controlled by using secondary particles with specific diameter ranges (e.g., 1-10 μm), which are large enough to provide good electrical contact but small enough to prevent penetration through the solid electrolyte layer
2Reliability
If the stack is pressed to unify solid particles and reduce interfacial resistance, then the electrical contact is improved, but the pressing force may cause secondary particles to penetrate through the solid electrolyte layer
Solution Approach 1:
The active material layer is designed with non-uniform particle distribution, concentrating secondary particles in regions where they provide electrical benefit while avoiding excessive concentration at interfaces where penetration risk is higher
Solution Approach 2:
The battery structure combines multiple materials with different properties: secondary particles for electrical conductivity, solid electrolyte for ion transport, and carefully controlled interfaces, creating a composite system that balances conductivity with penetration prevention
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 method effectively suppresses short circuits by ensuring that primary particles do not enter or penetrate the solid electrolyte layer, thereby enhancing the reliability and performance of all solid-state batteries.
Implementation Method 1
a second step of pressing the stack to constitute a compact, wherein in the first step, the active material layer contains a secondary particle of an active material, and in the second step, the secondary particle is crushed to primary particles by said pressing
Data Source
AI summary
It is suppressed that an active material particle enters into or penetrates through a solid electrolyte layer when an active material layer and the solid electrolyte layer are pressed and that short circuits between a cathode and an anode occur. A method for producing an all solid-state battery includes: a first step of stacking an active material layer over at least one surface of a solid electrolyte layer to constitute a stack; and a second step of pressing the stack to constitute a compact, wherein in the first step, the active material layer contains a secondary particle of an active material, and in the second step, the secondary particle is crushed to primary particles by said pressing, the secondary particle being present in an interfacial portion between the active material layer and the solid electrolyte layer.