Graphitization of unburned carbon from oil-fired fly ash applied for anode materials of high power lithium ion batteries
Resource
Materials Chemistry and Physics, 130(1-2), 309-315
Journal
Materials Chemistry and Physics
Pages
309-315
Date Issued
2011
Date
2011
Author(s)
Yeh, Tzoo-Shing
Wu, Yu-Shiang
Lee, Yuan-Haun
Abstract
Unburned carbon is an industrial waste product of oil-fired fly ash. From the viewpoint of waste recycling, using ground unburned carbon with an average size of 6 μm heat treatment at 2700 °C, and both charge and discharge at 0.1 C, yields the first columbic efficiency of about 93.6%. Moreover, after 50 cycles, the discharge capacity is 325.5 mAh g-1, and the capacity retention is about 97.5%. The two conditions tested for rate capability are as follows: First, a charge at 0.2 C rate and discharge at variable C-rates in which the unburned carbon after heat treatment at higher temperature exhibits a higher capacity in the 0.2-3 C region. However, unburned carbon with heat treatment at 2300 °C is a suitable material for the higher C-rate region (5-10 C). Second, for both charge and discharge at the same C-rate, the unburned carbon after heat treatment at higher temperature exhibits a higher capacity in the 0.2-0.5 C region; however, unburned carbon without graphitization treatment is a suitable material for the higher C-rate region (3-10 C). Based on TEM observations, the graphitization treatment samples had annular microstructure which has many active sites, improving the intercalation/deintercalation of lithium ions. Therefore, these results show that compared to natural graphite, graphitization of unburned carbon is more suitable for the anode materials of a high power battery. © 2011 Elsevier B.V. All rights reserved.
Subjects
Anode materials; Electrochemical characterization; Lithium-ion batteries; Unburned carbon
Other Subjects
Active site; After-heat treatment; Anode material; Average size; Capacity retention; Charge and discharge; Columbic efficiency; Discharge capacities; Electrochemical characterization; High power battery; High-power; Higher temperatures; Intercalation/deintercalation; Lithium ions; Lithium-ion battery; Natural graphite; Rate capabilities; TEM observations; Unburned carbons; Waste recycling; Anodes; Ashes; Characterization; Electric batteries; Energy conversion; Fly ash; Graphitization; Heat treatment; Ions; Lead acid batteries; Lithium; Lithium alloys; Lithium batteries; Lithium compounds; Graphite
Type
journal article
File(s)![Thumbnail Image]()
Loading...
Name
122.pdf
Size
23.45 KB
Format
Adobe PDF
Checksum
(MD5):4ed9d6dc663ad0d903574959c9afabb0