Materials

Active Carbon

• Biomass Selection

  • • Identify and select locally abundant biomass materials suitable for carbon activation

• Activation Process

  • • Activate the carbonized biomass using physical or chemical activation methods to create hierarchical pore structures

• Heteroatom Doping

  • • Introduce heteroatoms (nitrogen, oxygen, etc.) during or after the activation process to enhance electrochemical properties

• Characterization Techniques

  • • BET, SEM, TEM, and XPS

Hard Carbon

• Hard Carbon Synthesis

  • • Carbonize biomass using a process optimized for hard carbon formation

• Carbon Coating

  • • Apply a thin layer of carbon onto the hard carbon surface to improve conductivity and stability

• Characterization Techniques

  • • XRD, Raman spectroscopy, and TEM

Electrode

Electrode Preparation

• Mix the activated carbon or hard carbon with a conductive agent (e.g., carbon black) and a binder (e.g., PVDF)

• Coat the mixture onto a current collector (e.g., aluminum foil) to form the electrode

Electrode Drying & Treatment

• Dry the electrodes in a controlled environment

• Heat-treat the electrodes to enhance their stability

Presodiation of Hard Carbon-Based Electrode

• Pre-treat the hard carbon electrode with sodium ions to improve initial capacity and stability

• Perform electrochemical tests and material characterization after presodiation to evaluate the impact on performance

Device

Electrochemical Testing

• Perform cyclic voltammetry (CV), galvanostatic charge-discharge (GCD), and impedance spectroscopy to characterize the electrochemical behavior

Specific Capacitance and Energy Density Calculation

• Calculate specific capacitance and energy density based on electrochemical data

Electrode Drying & Treatment

• Dry the electrodes in a controlled environment

• Heat-treat the electrodes to enhance their stability

Cell Assembly & Testing

• Assemble a full Na-ion cell with the AC cathode and presodiated HC anode

• Conduct cycling tests and analyze the overall performance of the full cell

System

Energy Management & System Development

• System Modeling

  • • Develop a mathematical model for the Na-ion energy storage system

• Control Strategy

  • • Implement an energy management and control system based on the system model

• Optimization Algorithms

  • • Use engineering optimization techniques to improve the overall system performance

• Iterative Testing and Modification

  • • Iteratively test and modify the system components based on optimization results.