Total Iron Content of Lithium Iron Phosphate Battery based Cathode Material

The application describes a method to Total Iron Content in Lithium iron phosphate based cathode material of Lithium ion batteries.

Background

Most of the cathode materials used in lithium ion battery production are cobalt based. However, cobalt-free lithium iron phosphate (LiFePO₄) is growing in popularity for EV applications. It is the safest and most stable battery cathode material, as it does not produce oxygen upon decomposition. As LiFePO₄ is not a good electric conductor itself, it is mixed and calcinated with graphite during production.

The total iron content is a quality indicator of LiFePO₄ based cathode material. It is used to characterize the raw LiFePO₄ material as well as the finished, calcinated cathode material.

The total amount of iron (Fe, mainly consisting of Fe²⁺ and Fe³⁺), is determined by a redox titration using potassium dichromate K₂Cr₂O₇ as titrant and a platinum electrode as indicator in automated titration system.

This application note includes:

• Introduction
• Sample Preparation and Procedures
• Solutions and Chemicals
• Chemistry
• Instruments and Accessories
• Method in Detail
• Results and Remarks

And method files (.lmt and .xml) for direct import and implementation on the instrument.