Method for measuring content of ferrous iron and ferric iron in ferrous phosphate lithium anode material

A technology that applies lithium iron phosphate and cathode materials in the measurement of color/spectral characteristics, etc., can solve problems such as affecting the environment, chromium pollution, mercury pollution, etc., and achieve accurate results, accurate and reliable results, and high sensitivity.

Inactive Publication Date: 2012-01-18
NANOCHEM SYST SUZHOU
View PDF4 Cites 17 Cited by
  • Summary
  • Abstract
  • Description
  • Claims
  • Application Information

AI Technical Summary

Problems solved by technology

[0005] The content of ferric iron in lithium ferrous phosphate is trace or trace amount, and the titration method only consumes less potassium dichromate, resulting in increased systematic errors and accidental errors. big
The above-mentioned public titration method has a complicated operation ...

Method used

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
View more

Image

Smart Image Click on the blue labels to locate them in the text.
Viewing Examples
Smart Image
  • Method for measuring content of ferrous iron and ferric iron in ferrous phosphate lithium anode material
  • Method for measuring content of ferrous iron and ferric iron in ferrous phosphate lithium anode material

Examples

Experimental program
Comparison scheme
Effect test

Embodiment Construction

[0031] Determination of ferrous iron content (o-phenanthroline spectrophotometry)

[0032] Carry out following experimental test in the protective atmosphere device of the present invention that has provided argon protective atmosphere:

[0033] 1.1 Preparation of ferrous solution:

[0034] Step 1: Weigh LiFePO 4 Put 0.5000 g of the sample in a beaker, rinse the wall of the beaker with a small amount of water, add 40 ml of hydrochloric acid (1:1), cover with a watch glass, and place it on a low-temperature electric furnace to heat to a slight boil. After keeping for 20 min, remove and cool to room temperature, filter, transfer the filtrate into a 100 ml volumetric flask and add water to volume.

[0035] Step 2: According to the expected iron content in the sample, add 1.0 ml of the solution obtained in the first step above to a 1000 ml volumetric flask.

[0036] Step 3: Dilute to 60 ml with water, adjust the pH to 3 with hydrochloric acid solution (detected ...

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

PUM

No PUM Login to view more

Abstract

The invention discloses a method for measuring the content of ferrous iron and ferric iron in a ferrous phosphate lithium anode material, which is used for carrying out sample treatment and sample measurement under a protective atmosphere and comprises the following steps: measuring the content of the ferrous iron: dissolving the ferrous phosphate lithium anode material by using acid; then, when the pH of a solution is regulated to 2-9, adding phenanthroline to produce an orange complex with the ferrous iron; and carrying out a sample measurement process of measuring the absorbance of the orange complex by using a spectralphotometer, and measuring the content of the ferric iron: dissolving the ferrous phosphate lithium anode material by using the acid; when the pH of the solution is 1-3, adding sulfosalicylic acid to produce a purple complex with the ferric iron; and measuring the absorbance of the purple complex by using the spectralphotometer. The invention also discloses a protective atmosphere device designed to test the method for measuring the content of the ferrous iron and the ferric iron, which comprises an admission pipe, an exhaust pipe, a box body, an operating space and operating gloves, wherein the operating space is filled with inert gases, such as argon, helium, neon, nitrogen and carbon dioxide.

Description

technical field [0001] The invention relates to a method for detecting the quality of battery positive electrode materials, in particular to a method for detecting the content of divalent iron and ferric iron in the lithium iron phosphate positive electrode material. Background technique [0002] Compared with traditional lithium-ion batteries, lithium iron phosphate has become more and more popular in electric vehicles, power tools, energy storage devices, etc. due to its cheap price, environmental protection, good environmental compatibility, good cycle performance and high safety performance. ideal energy configuration. [0003] In the lithium iron phosphate positive electrode material, there is more or less trivalent iron as an impurity. The existence of ferric iron will increase the self-discharge of the lithium iron phosphate positive electrode material and decrease the specific capacity. Content is an important indicator to measure the performance of lithium iron pho...

Claims

the structure of the environmentally friendly knitted fabric provided by the present invention; figure 2 Flow chart of the yarn wrapping machine for environmentally friendly knitted fabrics and storage devices; image 3 Is the parameter map of the yarn covering machine
Login to view more

Application Information

Patent Timeline
no application Login to view more
IPC IPC(8): G01N21/31
Inventor 尤志宏董明李红兰仙梅
Owner NANOCHEM SYST SUZHOU
Who we serve
  • R&D Engineer
  • R&D Manager
  • IP Professional
Why Eureka
  • Industry Leading Data Capabilities
  • Powerful AI technology
  • Patent DNA Extraction
Social media
Try Eureka
PatSnap group products

Browse by: Latest US Patents, China's latest patents, Technical Efficacy Thesaurus, Application Domain, Technology Topic.

© 2024 PatSnap. All rights reserved.Legal|Privacy policy|Modern Slavery Act Transparency Statement|Sitemap