Facile Synthesis of Micrometer-sized Hierarchical Porous Si@C Anodes for High-Performance Lithium-Ion Batteries

Conference · Wed Jun 02 04:00:00 EDT 2021

OSTI ID:1785243

Hou, Xiaodong ^[1]; Xu, Shuai ^[2]; Sun, Di ^[3]; Zhang, Xin ^[4]; Zhao, Julia ^[5]

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1. Research Asst. Professor, Institute of Energy Studies, University of North Dakota.; Clearwater Clean Energy Conference
2. Graduate student, Institute for Energy Studies
3. Graduate student, Chemistry department, University of North Dakota.
4. graduate student, Institute of Energy Studies, University of North Dakota.
5. Professor, Chemistry department, University of North Dakota.

Extensive studies have been conducted to determine if replacing graphite anodes with silicon is feasible since silicon possesses a high capacity and is an abundant resource; however, Si anodes suffer significant volume changes during cycling, which pulverizes its structure and subsequently causes rapid capacity fading. We used SiO2 nanoparticles (nSiO2) and low-cost coal-derived humic acid as a feedstock to synthesize high performance Si-C anodes for Li-ion Batteries through spray drying, calcination, and magnesiothermic reductions. Our Si-C anodes features micrometer-sized porous Si coated with a graphitized carbon shell (mpSi@C). The hierarchical graphitized carbon shell and porous silicon structure relieve the mechanical stress of the Si phase upon cycling, which stabilizes the structure. This mpSi@C composite design allows for a high initial discharge capacity of 2199.9 mAh g-1 at 0.1 A g-1 and a cycling performance of 68% capacity retention after 100 cycles at 1.0 A g-1. The multipoint contact between the Si anode and C structure allows for a remarkable performance rate of 566.3 mAh g-1 at 5.0 A g-1.

• Research Organization: University of North Dakota
• Sponsoring Organization: USDOE
• Contributing Organization: National Energy Technology Laboratory through NETL-Penn State University Coalition for Fossil Energy Research
• DOE Contract Number: FE0026825
• OSTI ID: 1785243
• Report Number(s): DOE-UND-0026825
• Country of Publication: United States
• Language: English

Related Subjects

01 COAL, LIGNITE, AND PEAT
25 ENERGY STORAGE
36 MATERIALS SCIENCE
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
humic acid
porous silicon
magnesiothermic reduction
hierarchical structure
lithium-ion batteries