Multi-Layered Lithium Anode Protection for Aqueous Cells

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Lithium batteries face challenges with lithium anode protection due to reactivity, dendrite formation, and short cycle life, especially in aqueous and air environments, where existing protective coatings struggle to withstand the removal and re-plating of lithium ions and are inadequate in preventing corrosion and charge transport interference.

Innovation Solution

A multi-layered structure comprising single-ion conductive material layers and polymeric layers, with a separation layer, is introduced between the lithium anode and the electrolyte, allowing lithium ion passage while inhibiting electronic communication and preventing harmful species from reaching the anode, thereby enhancing cycle life and reducing corrosion.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If a protective coating is applied to the lithium anode, then corrosion is prevented and cycle life is extended, but the coating may interfere with charge transport and increase internal resistance

Engineering Contradiction:
Improvecycle lifeVSAvoidcharge transport interference
Core Design Contradiction:
ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent applies different materials with specific local properties to different regions of the anode structure. The protective coating is designed with local quality characteristics - being ion-conductive in the bulk but electron-blocking at the interface - to simultaneously protect against corrosion and maintain charge transport efficiency

Inventive Principle:
Principle #3Local quality

Solution Approach 2:

The patent employs composite protective coatings combining multiple materials with complementary properties. The composite structure integrates ion-conductive components for charge transport with corrosion-resistant components, achieving both protection and electrical functionality simultaneously

Inventive Principle:
Principle #40Composite materials

2Productivity

If the lithium anode is exposed to electrolyte, then charge transport is efficient, but dendrite formation and reaction with electrolyte occur

Engineering Contradiction:
Improvecharge transport efficiencyVSAvoiddendrite formation
Core Design Contradiction:
ProductivityVSObject-generated harmful factors

Solution Approach 1:

The patent introduces an intermediary protective coating between the lithium anode and electrolyte. This intermediary layer acts as a mediator that permits necessary ion transport while blocking harmful interactions, including dendrite formation and parasitic reactions with the electrolyte

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The protective coating is applied in advance before dendrite formation can occur. The pre-formed barrier prevents dendrite initiation and growth by blocking the direct contact between lithium metal and electrolyte, addressing the harmful effect before it manifests

Inventive Principle:
Principle #9Preliminary anti-action

3Reliability

If lithium ion conducting ceramic coating is applied, then anode protection is improved, but device complexity and manufacturing difficulty increase

Engineering Contradiction:
Improveanode protectionVSAvoidmanufacturing complexity
Core Design Contradiction:
ReliabilityVSDevice complexity

Solution Approach 1:

The patent modifies the parameters of protective coatings by adjusting composition, thickness, and deposition conditions to achieve optimal protection with simplified manufacturing. By changing these parameters, the patent reduces manufacturing complexity while maintaining anode protection effectiveness

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 multi-layered structure significantly extends the cycle life of lithium batteries by maintaining anode integrity, reducing corrosion, and ensuring efficient charge transport, even at high current densities, while maintaining a compact and lightweight design.

Implementation Method 1

a single-ion conductive layer separating the first layer from the second layer and substantially preventing electronic communication between the first and second layers

Methodology Applied
Scientific EffectIon conduction: Conduction (electrical)

Implementation Method 2

at least a portion of the ion-conductive material of the multi-layered structure contains voids at least partially filled with an auxiliary transport-inhibiting substance

Methodology Applied
Scientific EffectPermeation barrier: Permeation

Data Source

PatentEP1999818B1Electrode protection in both aqueous and non-aqueous electrochemical cells, including rechargeable lithium batteries
Publication Date: 2019.05.08 SION POWER CORP
  • EP1999818B1 patent drawingFigure 1
  • EP1999818B1 patent drawingFigure 2
  • EP1999818B1 patent drawingFigure 3

AI summary

Electrode protection in electrochemical cells, and more specifically, electrode protection in both aqueous and non-aqueous electrochemical cells, including rechargeable lithium batteries, are presented. Rechargeable batteries comprising lithium anodes for use in water and/or air environments, as well as non-aqueous and non-air environments are also described. In one embodiment, an electrochemical cell includes an anode comprising lithium and a multi-layered structure positioned between the anode and an electrolyte of the cell. A multi-layered structure can include at least a first single-ion conductive material layer (e.g., a lithiated metal layer), and at least a first polymeric layer positioned between the anode and the single-ion conductive material. The invention also can provide an electrode stabilization layer positioned within the electrode, i.e., between one portion and another portion of an electrode, to control depletion and re-plating of electrode material upon charge and discharge of a battery. Advantageously, electrochemical cells comprising combinations of structures described herein are not only compatible with environments that are typically unsuitable for lithium, but the cells may be also capable of displaying long cycle life, high lithium cycling efficiency, and high energy density.