Solid-State Lithium Battery Anode Composite Against Pores and Dendrites

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

All-solid lithium secondary batteries face challenges in improving energy density and maintaining the lifetime and safety due to the use of bulky solid electrolytes and lithium metal, which leads to pore generation and dendrite formation, reducing their operational efficiency and safety.

Innovation Solution

Incorporating platelet carbon nanofibers and silver nanoparticles in the negative electrode active material layer to enhance lithium ion mobility and storage, thereby improving charge/discharge efficiency and safety, while reducing the amount of silver nanoparticles to maintain price competitiveness.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If lithium metal is used as negative electrode active material layer to improve energy density, then energy density is improved, but pores are generated between solid electrolyte and metal layer and dendrites form on metal layer surface, degrading battery operation, lifetime and safety

Engineering Contradiction:

Improveenergy densityVSAvoidbattery operation and safety

Core Design Contradiction:

Use of energy by moving objectVSReliability

Solution Approach 1:

The patent uses a composite negative electrode active material layer comprising platelet carbon nanofibers and silver nanoparticles. The platelet carbon nanofibers provide a stable structure that prevents pore formation, while the silver nanoparticles facilitate lithium ion insertion/extraction and prevent dendrite formation, thus maintaining both high energy density and reliable operation

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The patent creates a heterogeneous structure where platelet carbon nanofibers and silver nanoparticles are distributed within the negative electrode active material layer. The platelet carbon nanofibers provide structural stability in certain regions while silver nanoparticles provide electrochemical activity in other regions, allowing simultaneous achievement of high energy density and operational reliability

Inventive Principle:

Principle #3Local quality

2Reliability

If end plate is disposed to apply high external pressure to prevent pore generation, then pore generation is prevented, but volume of battery is excessively increased, reducing energy density

Engineering Contradiction:

Improvepore preventionVSAvoidenergy density

Core Design Contradiction:

ReliabilityVSUse of energy by moving object

Solution Approach 1:

The patent removes the end plate component entirely by incorporating pore-preventing functionality directly into the negative electrode active material layer through the use of platelet carbon nanofibers. This eliminates the need for additional volume-consuming external pressure application mechanisms while maintaining pore prevention

Inventive Principle:

Principle #2Taking out (Extraction)

Solution Approach 2:

The platelet carbon nanofibers act as an intermediary between the solid electrolyte and lithium metal, providing a stable interface that prevents pore formation without requiring external mechanical pressure. This intermediary layer maintains contact integrity while avoiding the volume increase associated with end plates

Inventive Principle:

Principle #24Intermediary (Mediator)

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 use of platelet carbon nanofibers and silver nanoparticles effectively improves the initial charge/discharge efficiency and life characteristics of the battery by enhancing lithium ion mobility and storage, while minimizing energy density loss and maintaining cost-effectiveness.

Implementation Method 1

forming dry mixed powder including platelet carbon nanofibers and silver nanoparticles disposed on the platelet carbon nanofibers by reducing silver ions in a mixture of the silver ions and the platelet carbon nanofibers

Methodology Applied

Scientific EffectReduction: Reduction

Implementation Method 2

lithium ions are reduced and precipitated by the negative electrode active material layer during charge, and thus, the lithium ions may be effectively stored in a negative electrode

Methodology Applied

Scientific EffectReduction and precipitation: Precipitation

Implementation Method 3

the stored lithium may be dissolved in the form of lithium ions during discharge, and thus, the lithium ions may move to a positive electrode

Methodology Applied

Scientific EffectIon transport: Ion Exchange

Data Source

PatentUS20250015340A1All-solid lithium secondary battery and preparation method thereof

Publication Date: 2025.01.09 LG ENERGY SOLUTION LTD

AI summary

The present disclosure relates to an all-solid lithium secondary battery and a preparation method thereof, wherein the all-solid lithium secondary battery includes a positive electrode active material layer, a negative electrode active material layer, and a solid electrolyte layer disposed between the positive electrode active material layer and the negative electrode active material layer, wherein the negative electrode active material layer includes platelet carbon nanofibers (Platelet Carbon Nano Fiber, PCNF) and silver nanoparticles.