LMR Cathode Composition Doping for Voltage Fade and Rate Capability

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

Lithium and manganese rich (LMR) positive electrode active materials face challenges such as voltage fade, structural changes during cycling, and slower kinetics, which affect their long-term cycling stability and rate performance in lithium-ion batteries.

Innovation Solution

Incorporating small amounts of Tungsten (W), Tantalum (Ta), or Vanadium (V) via cation doping into LMR compositions, represented by the formula LiaMnbNic-x-aNx-bMa+bO2, to enhance electronic and ionic conductivity, structural stability, and electrochemical performance, thereby improving cycle performance and rate capability.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Use of energy by moving object

If LMR positive electrode active materials are used to achieve high gravimetric energy density, then energy density is improved, but voltage fade and structural changes occur during cycling

Engineering Contradiction:

Improvegravimetric energy densityVSAvoidstructural stability

Core Design Contradiction:

Use of energy by moving objectVSStability of the object's composition

Solution Approach 1:

The patent applies local quality by doping specific transition metal elements (Mn, Ni, Co) at controlled concentrations (a, b, c parameters) at specific lattice positions within the LMR material structure. This localized compositional control enhances structural stability at critical sites while preserving the high energy density characteristics of the overall LMR material.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs parameter changes by systematically varying the oxidation states of Mn (3.6-4.0) and Ni (2.0), and adjusting the stoichiometric parameters (a: 1.02-1.08, b: 0.51-0.53, c: 0.40-0.47) to optimize both energy density and structural stability. These parameter adjustments allow tuning of the material properties to resolve the contradiction between high energy density and structural stability.

Inventive Principle:

Principle #35Parameter changes

2Quantity of substance

If LMR materials are used to achieve high energy density, then capacity is improved, but slower kinetics and reduced rate performance occur

Engineering Contradiction:

ImprovecapacityVSAvoidrate performance

Core Design Contradiction:

Quantity of substanceVSSpeed

Solution Approach 1:

The patent applies parameter changes by optimizing the oxidation states (Mn: 3.6-4.0, Ni: 2.0) and stoichiometric ratios to enhance electronic conductivity and ionic transport kinetics. These parameter adjustments improve the charge-discharge rate performance while maintaining high capacity, resolving the contradiction between quantity of substance and speed.

Inventive Principle:

Principle #35Parameter changes

3Duration of action of moving object

If LMR materials undergo cycling to maintain operation, then duration of action is improved, but voltage fade and structural changes reduce reliability

Engineering Contradiction:

Improvecycling durationVSAvoidcycling stability

Core Design Contradiction:

Duration of action of moving objectVSReliability

Solution Approach 1:

The patent applies local quality by strategically doping transition metals at specific lattice positions with controlled concentrations, which stabilizes the local crystal structure during cycling and prevents voltage fade, thereby improving both cycling duration and reliability simultaneously.

Inventive Principle:

Principle #3Local quality

Solution Approach 2:

The patent employs composite materials by creating a multi-element LMR composition with Mn, Ni, Co, and other transition metals in specific ratios, forming a composite structure that combines the benefits of each element to enhance both cycling duration and reliability.

Inventive Principle:

Principle #40Composite materials

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 doped LMR materials exhibit improved voltage decay, increased capacity, and enhanced electrochemical properties, maintaining high energy density and stability in lithium-ion batteries.

Implementation Method 1

Incorporating small amounts of Tungsten (W), Tantalum (Ta), or Vanadium (V) via cation doping into LMR compositions... to enhance electronic and ionic conductivity

Methodology Applied

Scientific EffectElectron donation:

Implementation Method 2

Incorporating small amounts of Tungsten (W), Tantalum (Ta), or Vanadium (V) via cation doping into LMR compositions

Methodology Applied

Scientific EffectCation doping: Dopants

Data Source

PatentUS20260031342A1Lithium and manganese rich positive active material compositions

Publication Date: 2026.01.29 FORD GLOBAL TECH LLC

AI summary

A positive electrode active material for lithium-ion batteries may include a compound represented by the general formula LiaMnbNic-x-aNx-bMa+bO2, wherein a ranges from 1.02 to 1.08, b ranges from 0.51 to 0.53, c ranges from 0.40 to 0.47, x ranges from 0 to 0.1, a+b ranges from 0 to 0.05, N=Co, Cr, or a combination thereof, and M=W+6, Ta+5, V+5, or a combination thereof.