Composite LiFePO4 Carbon Coating for Higher Compaction Density
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current commercialized carbon-coated lithium iron phosphate materials have low tap/compaction density, which hinders the development of high-energy-density positive electrode materials for lithium ion batteries.
Innovation Solution
A composite lithium iron phosphate material is developed using a composition of an iron phosphate precursor, a lithium source, and a carbon source, where the carbon source includes synthetic polymer and biomass carbon sources, such as carbon fibers, to enhance compaction density and specific capacity.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Reliability
If carbon coating is applied to lithium iron phosphate, then conductivity is improved, but tap/compaction density decreases
Solution Approach 1:
The patent changes the physical and chemical parameters of the carbon coating by using a dual carbon source system (synthetic polymer carbon source and biomass carbon source) instead of conventional single carbon sources. This results in carbon coatings with optimized thickness, morphology, and composition that simultaneously improve conductivity and maintain higher compaction density compared to conventional carbon-coated lithium iron phosphate materials.
Solution Approach 2:
The patent employs a composite carbon coating structure formed from multiple carbon sources (synthetic polymer carbon source and biomass carbon source) that creates a multi-component carbon layer on the lithium iron phosphate particles. This composite carbon structure provides both the conductivity enhancement needed for battery performance and the density characteristics required for high-energy-density applications.
2Reliability
If carbon source amount is increased to improve conductivity, then specific capacity increases, but particle size distribution deteriorates
Solution Approach 1:
The patent optimizes the parameters of carbon source quantity and type by using a specific combination of synthetic polymer carbon source and biomass carbon source in controlled proportions. This parameter optimization ensures uniform carbon coating thickness and consistent particle size distribution while achieving the desired specific capacity enhancement through improved conductivity.
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 composite lithium iron phosphate material achieves improved compaction density and specific capacity, enhancing the performance of lithium ion batteries by promoting better particle grading and conductivity.
Implementation Method 1
The carbon source covers the iron phosphate precursor and the lithium source to obtain an orthorhombic composite lithium iron phosphate material
Implementation Method 2
The biomass carbon source includes carbon fibers
Data Source
AI summary
Disclosed is a composite lithium iron phosphate material, and a positive electrode and a lithium ion battery using the same. The composite lithium iron phosphate material is made of a composition comprising an iron phosphate precursor, a lithium source, and a carbon source, the carbon source covers the iron phosphate and the lithium source, the carbon source includes a synthetic polymer carbon source and a biomass carbon source, and the biomass carbon source includes carbon fibers.