Lithium Ion-Sulfur Battery Intercalation Electrode Dendrite Prevention

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Existing lithium-ion batteries have insufficient energy density and charge/discharge durability due to dendrite formation when lithium ions are repeatedly cycled, limiting their application in next-generation electric vehicles.

Innovation Solution

A lithium ion-sulfur battery structure is introduced, where an intercalation electrode is interposed between the lithium metal and sulfur electrode, allowing lithium ions to be intercalated into the electrode during initial use, preventing dendrite formation and enhancing sulfur electrode capacity, thus improving charge/discharge efficiency and durability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If lithium metal is used as the negative electrode to achieve high energy density, then the initial capacity is very high, but dendrite is deposited on the surface of the metal during charge/discharge cycles, reducing charge/discharge efficiency and safety

Engineering Contradiction:

Improveenergy densityVSAvoidcharge/discharge durability

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

An intercalation electrode is introduced as an intermediary component between the lithium metal anode and the sulfur cathode. This intermediate layer accepts lithium ions during initial charging and serves as the active negative electrode during subsequent charge/discharge cycles, preventing direct contact between lithium metal and the electrolyte, thereby eliminating dendrite formation while preserving the high energy density benefits of lithium metal

Inventive Principle:

Principle #24Intermediary (Mediator)

Solution Approach 2:

The intercalation electrode is pre-charged with lithium ions during an initial charging step before the battery enters normal operation. This preliminary action transforms the lithium metal from a direct electrode into a lithium ion source, and the intercalation electrode becomes the working negative electrode, preventing dendrite formation from the outset

Inventive Principle:

Principle #10Preliminary action

2Reliability

If conventional lithium-ion battery structure is used to ensure safety, then dendrite formation is avoided, but the energy density is insufficient to run about 500 km

Engineering Contradiction:

ImprovesafetyVSAvoidenergy density

Core Design Contradiction:

ReliabilityVSQuantity of substance

Solution Approach 1:

The battery employs a composite structure combining lithium metal (for high capacity), intercalation electrode material (for safety and structural stability), and sulfur cathode (for high energy density). This composite approach integrates the advantages of different materials: lithium metal provides high energy density, the intercalation electrode provides safety by preventing dendrites, and sulfur provides additional capacity

Inventive Principle:

Principle #40Composite materials

Solution Approach 2:

The negative electrode function is segmented into two distinct components: lithium metal that serves solely as a lithium ion reservoir, and the intercalation electrode that serves as the active negative electrode during operation. This segmentation allows each component to perform its specialized function optimally - lithium metal provides ions without forming dendrites, while the intercalation electrode provides a safe, stable working electrode

Inventive Principle:

Principle #1Segmentation

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 configuration significantly increases energy density and prevents dendrite formation, enhancing the charge/discharge durability of lithium ion-sulfur batteries, making them suitable for next-generation electric vehicles with comparable running distance and durability to conventional internal combustion engine vehicles.

Implementation Method 1

has a structure capable of causing an intercalation reaction, and is used as a negative electrode after the lithium ions are intercalated from the lithium metal to be charged and discharged together with the sulfur electrode

Methodology Applied

Scientific EffectIntercalation reaction: Absorption (physical)

Implementation Method 2

an organic or inorganic electrolyte, in which lithium metal is used as a negative electrode and sulfur is used as a positive electrode to repeat charge and discharge cycles by an oxidation-reduction reaction

Methodology Applied

Scientific EffectIonic conduction: Conduction (electrical)

Implementation Method 3

sulfur is used as a positive electrode to repeat charge and discharge cycles by an oxidation-reduction reaction

Methodology Applied

Scientific EffectOxidation-reduction reaction: Redox Reactions

Data Source

PatentUS9123968B2Lithium ion-sulfur battery and electrode for the same

Publication Date: 2015.09.01 HYUNDAI MOTOR CO LTD

AI summary

Disclosed is a lithium ion-sulfur battery including a lithium metal used as a supply source of lithium ions, a sulfur electrode used as a positive electrode and an intercalation electrode. The intercalation electrode is (i) interposed between the lithium metal and the sulfur electrode, (ii) has a structure capable of causing an intercalation reaction, and (iii) is used as a negative electrode after the lithium ions are intercalated from the lithium metal to be charged and discharged together with the sulfur electrode. The lithium metal is used only to intercalate the lithium ions into the intercalation electrode during initial use, and the intercalation electrode, into which the lithium ions are intercalated, is used as a negative electrode during actual use. Therefore, it is possible to prevent the formation of dendrite caused when the lithium ions are used as the negative electrode, and thus the charge/discharge durability is improved.