Suitable binder for Li-ion battery anode produced from rice husk

Area of Science:

• Materials Science
• Electrochemistry
• Energy Storage

Background:

• Rice husk (RH) is a sustainable, abundant lignocellulosic biomass rich in silicon oxides (SiO_x).
• RH-derived materials are explored as low-cost, eco-friendly alternatives for lithium-ion battery (Li-ion battery) anodes.
• Developing effective binders is crucial for stabilizing the performance of silicon-based anodes.

Purpose of the Study:

• To prepare a rice husk-derived carbon/silicon oxide composite (RHC) for Li-ion battery anodes.
• To evaluate the performance of RHC electrodes using different aqueous binders: polyacrylic acid (PAA) and carboxymethyl cellulose/styrene butadiene rubber (CMC/SBR).
• To investigate the role of the binder in electrode stability and electrochemical performance.

Main Methods:

• Carbonization of rice husk at 1000 °C to produce RHC.
• Fabrication of RHC electrodes using PAA and CMC/SBR binders in a half-cell configuration.
• Electrochemical testing including cycling performance, rate capability, and impedance analysis.
• Complete lithiation of the RHC electrode by shorting the cell for 24 hours.

Main Results:

• The RHC electrode fabricated with PAA demonstrated superior specific capacity for Li-ion extraction during cycling compared to CMC/SBR.
• PAA binder enhanced electrode structural integrity and mitigated the increase in resistance caused by interphase film formation.
• Impedance analysis revealed improved stability in the PAA-bound electrode.

Conclusions:

• Polyacrylic acid is a highly effective binder for RHC anodes in Li-ion batteries.
• The strong affinity between PAA and SiO_x in the RHC material stabilizes anodic performance.
• RHC with PAA offers a promising pathway for developing high-performance, sustainable Li-ion battery anodes.