LiMPO4 Production via Lithium Polyacrylate Wet Grinding

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Existing methods for producing lithium metal phosphates for battery applications face challenges in achieving a simplified, economical, and contamination-free process with uniform particle size distribution, as they require complex reaction control and high shearing forces, leading to difficulties in mixing and grinding precursor suspensions.

Innovation Solution

A method involving a dry mixture of lithium, metal, and phosphate compounds, followed by conversion to LiMPO4, wet grinding with lithium polyacrylate to reduce viscosity, and subsequent drying, which allows for improved grindability and finer particle sizes without the need for high shearing forces or complex precursor suspension handling.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Manufacturing precision

If a precursor suspension is used for producing LiMPO4, then uniform homogeneous crystals with low particle size distribution can be achieved, but the suspension becomes highly viscous and difficult to mix and stir

Engineering Contradiction:
Improveparticle size distributionVSAvoidmixing and stirring
Core Design Contradiction:
Manufacturing precisionVSEase of operation

Solution Approach 1:

Lithium polyacrylate is introduced as a dispersant intermediary between the solid particles and water in the precursor suspension. This dispersant reduces particle agglomeration and lowers the viscosity of the suspension, making it easier to mix and stir while still achieving uniform homogeneous crystals with low particle size distribution after conversion.

Inventive Principle:
Principle #24Intermediary (Mediator)

Solution Approach 2:

The invention changes the chemical composition parameters of the suspension by adding lithium polyacrylate dispersant. This modification alters the rheological properties of the suspension, reducing its viscosity and improving flow characteristics, thereby facilitating mixing and stirring operations while maintaining the ability to produce uniform particles.

Inventive Principle:
Principle #35Parameter changes

2Manufacturing precision

If dispersion or grinding treatment is applied to reduce particle size, then uniform crystals with D90 < 50 μm can be obtained, but complex reaction control and individual dissolution of reactants are required

Engineering Contradiction:
Improveparticle size distributionVSAvoidreaction control
Core Design Contradiction:
Manufacturing precisionVSDevice complexity

Solution Approach 1:

The invention merges the dissolution of reactants and the formation of the precursor suspension into a single simplified step. By using lithium polyacrylate as a dispersant, all reactants can be dissolved and mixed together in one process, eliminating the need for individual dissolution steps and complex reaction control while still achieving uniform particles with D90 < 50 μm after conversion.

Inventive Principle:
Principle #5Merging (Combining)

3Manufacturing precision

If high shearing forces are used for grinding precursor suspension, then fine particle size can be achieved, but energy consumption increases

Engineering Contradiction:
Improveparticle sizeVSAvoidenergy consumption
Core Design Contradiction:
Manufacturing precisionVSUse of energy by moving object

Solution Approach 1:

Lithium polyacrylate acts as a mediator that reduces the energy required for grinding by preventing particle agglomeration and facilitating easier particle separation. The dispersant creates a more fluid suspension that requires less mechanical energy to achieve fine particle sizes, thereby reducing overall energy consumption while maintaining manufacturing precision.

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

This method significantly reduces viscosity, enabling easier and more economical grinding to achieve desired particle sizes, improving the production efficiency and purity of lithium metal phosphates while minimizing environmental impact and energy consumption.

Implementation Method 1

by adding the lithium polyacrylate, the viscosity can be substantially reduced, such that the grindability of the LiMPO4 is decisively improved

Methodology Applied
Scientific EffectViscosity reduction by polymer additive:

Implementation Method 2

wet grinding the LiMPO4 by adding water and lithium polyacrylate

Methodology Applied
Scientific EffectMechanical grinding: Abrasion

Implementation Method 3

drying

Methodology Applied
Scientific EffectEvaporation: Evaporation

Data Source

PatentUS9871252B2Method for producing lithium metal phosphate
Publication Date: 2018.01.16 BK GIULINI GMBH

AI summary

Method for the production of lithium metal phosphate, wherein a dry mixture containing a lithium compound, a metal compound, wherein the metal is selected from Fe, Mn and mixtures thereof, and a phosphate is provided, the dry mixture is converted to LiMPO4 and the LiMPO4 is wet ground by adding water and lithium polyacrylate and dried.