Two step pyrolysis synthesis method of graphite-enhanced Nano-Si/Pitch composite as long cycle life anode for lithium-ion batteries

• Published in: Journal of alloys and compounds Vol. 976; p. 173229
• Main Authors: Nyamtara, Kelvin Jenerali, Song, Jong Kwon, Karima, Neema Cyril, Kim, Sung Hoon, Nguyen, Manh Cuong, Duong, Thi Phuong Mai, Lee, Kyung Jin, Ahn, Wook
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 05.03.2024
• Subjects: Lithium-ion batteries; Nanocomposite; Pitch; Pyrolysis; Recycled industrial waste; Silicon; Lithium-ion batteries; Pitch; Pyrolysis; Silicon; Nanocomposite; Recycled industrial waste
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2023.173229

Energy storage devices have become the dominant power source in various fields due to their capacity, lifespan, and eco-friendliness. However, there is a need to develop new energy storage devices with higher energy and power density to meet increasing energy demands. Silicon-based anode materials have considerable potential for developing long-lasting, high-capacity energy storage devices, specifically lithium-ion batteries. However, the practical use of these batteries faces challenges like significant volume variations, silicon instability during charging and discharging, and restricted conductivity. This work used silicon nanoparticles from waste industrial solar cells and mixed them with pitch derived from coal tar in a tetrahydrofuran (THF) solvent to form a homogenous Si@Pitch nanocomposite. Pitch-derived carbon helps hold the silicon particles together, reducing the detrimental effects of volume expansion. It acts as a matrix that accommodates the structural changes in silicon during lithiation and delithiation. The Pyrolyzed Si@Pitch-2:1 nanocomposite electrode developed through an efficient two-step pyrolysis technique demonstrated outstanding performance. When charged at a rate of 500 mA·g−1 over 200 cycles, it showed a high discharge capacity of 1524 mAh·g−1, with an average coulombic efficiency of 99.8% and a discharge capacity retention of 75.7%. Combining silicon nanoparticles and pitch derived from recycled industrial waste contributes to the impressive results. This efficient synthesis method can improve the anode materials used in lithium-ion batteries. [Display omitted] •Si nanoparticles are obtained from recycled industrial waste from solar cells.•The two-step pyrolysis synthesis method yields a high Si content Si@Pitch-2:1 composite.•Incorporating Si nanoparticles in pitch ensures stability and conductivity, extending the life cycle.•After 130 cycles, Pyrolyzed Si@Pitch-2:1 anode shows 1122 mAh.g−1, 90.3% retention at 1000 mA·g−1.