Hybrid Anode Electrode Structure for Fast-Charging Battery Cells

Solution Overview

Problem

Battery cells, particularly those in electric vehicles, face challenges with fast charge capabilities and lithium plating issues due to the charge potential of graphite and Si/graphite anode electrodes, which limit their performance and safety during rapid charging.

Innovation Solution

The development of hybrid anode electrodes that combine silicon-based materials with lithium titanium oxide (LTO) derivatives, hard carbon, and titanium niobium oxide (TNO), optimized with specific weight percentages and layer configurations, to enhance charge potential and mitigate lithium plating.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Quantity of substance

If graphite and Si/graphite anode electrodes are used, then battery cell capacity is improved, but lithium plating occurs during fast charging reducing safety and performance

Engineering Contradiction:

Improvebattery cell capacityVSAvoidfast charge capability

Core Design Contradiction:

Quantity of substanceVSReliability

Solution Approach 1:

The anode electrode is segmented into multiple functional layers: a first anode active material layer containing graphite or Si/graphite for high capacity, and a second anode active material layer containing LTO or TNO derivatives for fast charging stability. This segmentation allows each layer to perform its specialized function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent creates a composite anode electrode structure combining two distinct anode active material layers with different electrochemical properties. The first layer provides high capacity while the second layer provides structural stability and prevents lithium plating during fast charging, achieving a synergistic effect that resolves the technical contradiction.

Inventive Principle:

Principle #40Composite materials

2Quantity of substance

If graphite and Si/graphite anode electrodes are used, then battery cell capacity is improved, but lithium plating issues arise limiting performance during rapid charging

Engineering Contradiction:

Improvebattery cell capacityVSAvoidlithium plating

Core Design Contradiction:

Quantity of substanceVSObject-generated harmful factors

Solution Approach 1:

The anode electrode is segmented into multiple functional layers: a first anode active material layer containing graphite or Si/graphite for high capacity, and a second anode active material layer containing LTO or TNO derivatives for fast charging stability. This segmentation allows each layer to perform its specialized function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent converts the potential harm of lithium plating into a benefit by using the LTO/TNO derivative layer as a protective buffer. This layer accepts lithium ions during charging, preventing them from plating on the graphite/Si-graphite layer, and then releases them during discharge, thereby eliminating the harmful effect while maintaining high capacity.

Inventive Principle:

Principle #22Blessing in disguise (Convert harm into benefit)

3Reliability

If hybrid anode electrodes with LTO and TNO derivatives are used, then fast charge capability is improved, but anode electrode structure complexity increases

Engineering Contradiction:

Improvefast charge capabilityVSAvoidanode electrode structure

Core Design Contradiction:

ReliabilityVSDevice complexity

Solution Approach 1:

The anode electrode is segmented into multiple functional layers: a first anode active material layer containing graphite or Si/graphite for high capacity, and a second anode active material layer containing LTO or TNO derivatives for fast charging stability. This segmentation allows each layer to perform its specialized function without compromising the other.

Inventive Principle:

Principle #1Segmentation

Solution Approach 2:

The patent achieves multi-functionality within the anode electrode structure. The separator layer serves dual purposes: it prevents direct contact between anode and cathode while also acting as a mechanical support for the hybrid anode electrode assembly. The current collector provides both electrical conductivity and structural support, reducing overall complexity despite the multi-layer design.

Inventive Principle:

Principle #6Universality (Multi-functionality)

Data Source

PatentUS20240405196A1Battery cells including hybrid anode electrodes

Publication Date: 2024.12.05 GM GLOBAL TECHNOLOGY OPERATIONS LLC

AI summary

An anode electrode for a battery cell includes an anode current collector. An anode active material layer comprising a first active material comprising silicon and a second active material comprising at least one of lithium titanium oxide (LTO) and a LTO derivative including LTO doped with a transition metal.