Biphasic Battery Separator for Lithium Dendrite Blocking
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Solid-state lithium metal batteries (SSLMBs) with lithium metal anodes and lithium lanthanum zirconium oxide (LLZO) solid-state electrolytes face issues with lithium dendrite formation, leading to decreased performance and battery failure due to non-uniform current density and misshaped separators.
Innovation Solution
A biphasic component is introduced, comprising a first ceramic phase with pores and a second solid phase within those pores, acting as a separator to provide a continuous ion conduction path and prevent dendrite growth, with the second solid phase being impermeable to liquid electrolyte and exhibiting specific conductivity ranges.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If a two-layer separator is used to address dendrite formation, then dendrite growth is inhibited, but the separator becomes misshaped during simultaneous sintering
Solution Approach 1:
The patent divides the separator function into two distinct components: a porous ceramic layer for mechanical support and dendrite blocking, and a solid-state electrolyte layer for ionic conduction. These layers are formed separately rather than simultaneously sintered, avoiding the flatness issues associated with multi-layer sintering while maintaining dendrite prevention capabilities.
2Device complexity
If lithium metal anode directly contacts the solid-state electrolyte, then battery structure is simplified, but lithium dendrites form at the anode
Solution Approach 1:
The patent introduces a porous ceramic layer as an intermediary between the lithium metal anode and the solid-state electrolyte. This intermediate layer serves as a physical barrier to dendrite formation while maintaining electrical and ionic connectivity. The ceramic layer mediates the interaction between the anode and electrolyte, preventing direct contact that would lead to dendrites while preserving battery performance.
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 biphasic component ensures uniform current density, prevents dendrite formation, and maintains battery performance by providing a stable physical barrier between the anode and cathode, enhancing energy density and lifespan.
Implementation Method 1
the first ceramic phase provides a continuous conduction path for the lithium ions through the separator portion to the anode portion
Implementation Method 2
provides a stable physical barrier between the anode and cathode
Data Source
AI summary
A rechargeable battery includes: (1) a cathode current collector separated from an anode current collector by a battery distance, the anode current collector and the cathode current collector at least partially defining a battery space; (2) a cathode disposed within the battery space capable of storing alkali ions; and (3) a biphasic component disposed within the battery space between the anode current collector and the cathode, the biphasic component comprising (a) a first ceramic phase, (b) pores throughout the first ceramic phase, and (c) a second solid phase disposed within the pores of the first ceramic phase throughout (i) a separator portion of the biphasic component but not throughout (ii) an anode portion of the biphasic component, the separator portion being disposed between the anode portion and the cathode and forming a physical barrier between the pores through the first ceramic phase at the anode portion and the cathode.