LMFP Cathode Composition With Lithium-Rich Additive for Stable Cycling

Resolve Bottlenecks,
Find Innovative SolutionsGenerate Solutions

Solution Overview

Problem

The cycle performance of lithium manganese iron phosphate (LMFP) materials in lithium-ion batteries is inadequate due to issues like iron and manganese dissolution, and adding lithium-rich lithium ferrite (LFO) beyond 2% leads to gas production and reduced cycle improvement effects.

Innovation Solution

Incorporating lithium-rich manganese-based material particles with a controlled Li2MnO3 phase proportion of less than 0.5 into lithium iron manganese phosphate particles, along with a specific mass percentage and particle size ratio, to enhance the cycle and stabilizing performance of the positive electrode active material.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Reliability

If lithium-rich lithium ferrite (LFO) is added to improve cycle performance of LMFP material, then cycle performance is improved, but gas production increases and gas spots appear at negative electrode interface

Engineering Contradiction:

Improvecycle performanceVSAvoidgas production

Core Design Contradiction:

ReliabilityVSObject-generated harmful factors

Solution Approach 1:

The patent changes the chemical composition parameters by using lithium-rich manganese phosphate (Li1+xMn2-x-yO4-δ) with controlled lithium excess (x) and oxygen deficiency (δ), replacing the conventional lithium-rich lithium ferrite (LFO) additive. This parameter adjustment allows achieving cycle performance improvement without the harmful gas production effect

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent creates a composite positive electrode material system combining lithium iron manganese phosphate (LMFP) particles with lithium-rich manganese phosphate particles. This composite structure synergistically improves cycle performance while avoiding the gas generation problem associated with LFO additives

Inventive Principle:

Principle #40Composite materials

2Reliability

If more than 2% LFO material is added to effectively improve cycle performance, then cycle performance is improved, but serious gas spots appear at negative electrode interface reducing the improvement effect

Engineering Contradiction:

Improvecycle performanceVSAvoidgas spots at negative electrode interface

Core Design Contradiction:

ReliabilityVSObject-affected harmful factors

Solution Approach 1:

The patent modifies the chemical parameters by controlling the lithium excess ratio (x) and oxygen deficiency (δ) in lithium-rich manganese phosphate, and optimizing the mass percentage ratio between LMFP and LMP particles. This enables achieving effective cycle performance improvement without generating serious gas spots at the negative electrode interface

Inventive Principle:

Principle #35Parameter changes

Solution Approach 2:

The patent converts the potential harm of adding lithium-rich material (which could cause gas production) into a benefit by carefully controlling the oxygen deficiency and lithium excess parameters, transforming the material into one that improves cycle performance without the harmful side effects

Inventive Principle:

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

Data Source

PatentEP4693477A1Positive electrode active material, electrically conductive slurry and secondary battery

Publication Date: 2026.02.11 EVE POWER CO LTD

AI summary

The present disclosure provides a positive electrode active material, a conductive slurry and a secondary battery, and relates to the technical field of the secondary battery. The present disclosure improves the cycle performance and the stabilizing performance of a secondary battery having the positive electrode active material by adding the lithium-rich manganese-based material particles in the lithium iron manganese phosphate particles and controlling the proportion of Li2MnO3 phase in the lithium-rich manganese-based material to be less than 0.5.