Poly (acrylic acid)-modified silicon as an active material for anodes in advancing lithium-ion battery performance

Abstract

The integration of nanomaterials holds great promise for enhancing the performance of lithium-ion batteries (LIBs). Among these, nano-silicon (Si) stands out for its high theoretical capacity, but suffers from significant volume expansion during lithiation/delithiation cycles, leading to rapid capacity fading and electrode degradation. To address this challenge, poly (acrylic acid) (PAA) emerges as a promising candidate for surface modification of nano-silicon due to its ability to form a stable and flexible polymer layer. This manuscript investigates the synthesis and characterization of poly (acrylic acid)-modified nano-silicon (PAA@Si) as an electrode material for LIBs. The PAA modification not only mitigates the volume expansion of Si nanoparticles but also provides additional functionalities such as enhanced electronic conductivity and improved electrolyte compatibility. It is observed that the capacity retention of the PAA@Si anode is 56 % after 300 cycles compared to the silicon anode. Electrochemical performance evaluations demonstrate that PAA@Si electrodes exhibit superior cycling stability and rate capability compared to pristine Si electrodes. Furthermore, insights into the structure-property relationships elucidate the mechanisms underlying the enhanced battery performance. The findings presented herein highlight the potential of PAA-modified nano-silicon as a viable candidate for next-generation LIBs with enhanced energy storage and longevity.