There are significant differences in the index requirements for graphitized petroleum coke across different application fields. In the field of lithium-ion battery anode materials, emphasis is placed on electrochemical performance, particle size distribution, specific surface area, and purity control. In contrast, the field of electrode rods (such as graphite electrodes) places greater importance on conductivity, mechanical strength, thermal stability, and ash content control. A detailed analysis is provided below:
I. Lithium-ion Battery Anode Material Field
- Electrochemical Performance as the Core Indicator
Initial Charge/Discharge Specific Capacity: It must reach ≥350.0 mAh/g (National Standard GB/T 24533-2019) to ensure battery energy density. Initial Coulombic Efficiency: A requirement of ≥92.6% reflects the reversible capacity proportion of the material during the first cycle. Crystal Structure Parameters: The (002) plane spacing (d002) is controlled through X-ray diffraction (XRD) testing to optimize graphitization degree, reduce lattice defects, and enhance electron mobility. 2. Particle Size Distribution and Specific Surface Area
Particle Size Distribution: The average particle size (D50) and distribution width need to be controlled to optimize the battery slurry preparation process and volumetric energy density. Small particles filling the voids of large particles can improve compaction density. Specific Surface Area: A balance must be struck between reaction activity and initial capacity loss. Excessive specific surface area increases binder usage and internal resistance, while insufficient specific surface area limits lithium-ion deintercalation efficiency. 3. Purity and Impurity Control
Fixed Carbon Content: A requirement of ≥99.5% is necessary to minimize the impact of inactive components on electrochemical performance. Moisture and pH Value: Strict control is required to avoid material moisture absorption or reactions with the electrolyte, which can affect the stability of the slurry preparation process.
II. Electrode Rod (e.g., Graphite Electrode) Field
- Conductivity and Mechanical Strength
Resistivity: It must be as low as the μΩ·m level to reduce energy loss during electrode use. Flexural Strength: High flexural strength is required to resist mechanical stress during use and prevent breakage. Elastic Modulus: A balance between rigidity and toughness is necessary to avoid cracking due to thermal shock or mechanical vibration. 2. Thermal Stability and Oxidation Resistance
Thermal Expansion Coefficient: It must be low to minimize dimensional changes at high temperatures and prevent poor contact between the electrode and furnace charge. Ash Content: It must be ≤0.5% to reduce the impact of impurities on electrode oxidation resistance. Metal elements in ash can accelerate electrode oxidation and shorten service life. 3. Manufacturing Process Adaptability
Bulk Density: High bulk density is necessary to enhance electrode compactness and improve conductivity and oxidation resistance. Impregnation and Graphitization Process: Multiple impregnations and high-temperature graphitization (≥2800°C) are required to enhance crystal orderliness and reduce resistivity.
III. Indicator Prioritization Driven by Application Scenarios Lithium-ion Battery Anode Materials: They must meet the demands for high energy density and long cycle life, hence the stringent requirements for electrochemical performance, particle size distribution, and purity. Electrode Rods: They need to operate stably under high temperatures and high current densities, thus the greater emphasis on conductivity, mechanical strength, and thermal stability.
Post time: Oct-15-2025