Porous Electrode Coating to Suppress Battery Dendrite Growth

Solution Overview

Problem

Rechargeable lithium metal batteries face issues with dendrite formation during charging, leading to cycle life and safety problems, and existing solutions like solid polymer electrolyte suffer from low conductivity and modulus trade-offs.

Innovation Solution

A porous conductive electrode with an insulating layer that partially covers the conductive surface, incorporating active metals like lithium, sodium, or aluminum, where the insulating layer is electronically and ionically non-conductive, inhibiting dendrite growth while allowing electrolyte flow.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If solid polymer electrolyte is used to resist dendrite, then dendrite resistance is improved, but conductivity deteriorates (low conductivity in range of 10^-6 to 10^-4 Siem)

Engineering Contradiction:

Improvedendrite resistanceVSAvoidconductivity

Core Design Contradiction:

ReliabilityVSLoss of energy

Solution Approach 1:

The electrolyte system is segmented into two distinct functional layers: a solid polymer electrolyte layer (SPE) for dendrite resistance and a liquid electrolyte layer for high ionic conductivity. This segmentation allows each layer to optimize its specific function without compromising the other, resolving the contradiction between dendrite resistance and conductivity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention uses a composite electrolyte system combining solid polymer electrolyte and liquid electrolyte in a layered structure. The composite structure leverages the advantages of both materials: the solid polymer provides mechanical strength and dendrite resistance, while the liquid electrolyte provides high ionic conductivity, thus resolving the trade-off between these two properties.

Inventive Principle:

Principle #40Composite materials

2Reliability

If solid polymer electrolyte is used to resist dendrite, then dendrite resistance is improved, but modulus deteriorates (needs high modulus to resist dendrite)

Engineering Contradiction:

Improvedendrite resistanceVSAvoidmodulus

Core Design Contradiction:

ReliabilityVSStrength

Solution Approach 1:

The electrolyte system is segmented into two distinct functional layers: a solid polymer electrolyte layer (SPE) for dendrite resistance and a liquid electrolyte layer for high ionic conductivity. This segmentation allows each layer to optimize its specific function without compromising the other, resolving the contradiction between dendrite resistance and conductivity.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The invention uses a composite electrolyte system combining solid polymer electrolyte and liquid electrolyte in a layered structure. The composite structure leverages the advantages of both materials: the solid polymer provides mechanical strength and dendrite resistance, while the liquid electrolyte provides high ionic conductivity, thus resolving the trade-off between these two properties.

Inventive Principle:

Principle #40Composite materials

3Reliability

If insulating layer completely covers conductive surface, then dendrite growth is prevented, but ion flow is blocked

Engineering Contradiction:

Improvedendrite preventionVSAvoidion flow

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The insulating layer is applied with local quality variation: it covers portions of the conductive surface to prevent dendrite growth while leaving other portions exposed to allow ion flow. This selective coverage resolves the contradiction between dendrite prevention and ion transport by making the insulating property spatially non-uniform.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

Instead of complete coverage, the insulating layer is applied partially to the conductive surface. This partial action allows the system to achieve sufficient dendrite prevention while maintaining adequate ion flow pathways, resolving the contradiction between these two requirements.

Inventive Principle:

Principle #16Partial or excessive action

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 electrode design enhances energy density, improves cycle life, and ensures safety by preventing dendrite growth, with the insulating layer allowing ion flow without conducting electricity.

Implementation Method 1

an insulating layer that is made of material that is both electronically and ionically non-conductive

Methodology Applied

Scientific EffectElectrical insulation: Electrical Resistance

Implementation Method 2

the insulating material partially covers the conductive surface of the above-mentioned porous conductive layer

Methodology Applied

Scientific EffectIon transport through porous material: Porosity

Data Source

PatentUS12548791B2Porous electrode for electrochemical cells

Publication Date: 2026.02.10 LIBAMA POWER CORP

AI summary

A porous electrode and methods of making the same are described. The porous electrode is comprised of a porous conductive layer and an insulating layer, where the pores inside the conductive layer function as mini-containers for the active metals for rechargeable batteries, and the insulating layer covers the top surface of the conductive layer and blocks the sites where active metal dendrites would otherwise preferentially grow. An example of such electrodes is a porous copper foil with top surface coated with polyvinylene difluoride. Electrochemical cells containing the invented electrodes, such as rechargeable lithium battery, sodium battery and aluminum battery, have good cycle life and safety performance.