• Title/Summary/Keyword: KRICT

Search Result 419, Processing Time 0.025 seconds

Effects of Pitch Softening Point-based on Soft Carbon Anode for Initial Efficiency and Rate Performance (피치계 소프트 카본 음극재 제조 시 피치의 연화점이 음극재 초기 효율 및 율속 특성에 미치는 영향)

  • Kim, Kyung Soo;Im, Ji Sun;Lee, Jong Dae;Kim, Ji Hong;Hwang, Jin Ung
    • Applied Chemistry for Engineering
    • /
    • v.30 no.3
    • /
    • pp.331-336
    • /
    • 2019

  • In this study, required properties and optimized procedure conditions for the pitch based soft carbon anode of lithium ion battery was investigated for improving the initial efficiency and rate performance. Each petroleum residue was thermally treated at 360, 370, and $410^{\circ}C$ for 3 hours to synthesis a pitch and the corresponding pitch shows the softening point of 86, 98, and $152^{\circ}C$, respectively. The elemental analysis and thermal characteristics of the pitch were investigated by EA analysis and TGA. It was noted that the low H/C and improved thermal stability were obtained with the high softening point. The obtained pitch was carbonized at $1,200^{\circ}C$ for 1 hour to produce a soft carbon based anode. As a result of investigating the crystal structure by XRD analysis, it was found that the crystallinity of soft carbon increased with increasing the softening point. It was considered that relatively higher boiling components and decreases in the evaporation component resulted the components participation for cyclization during the heat treatment process. The soft carbon based anode with an improved crystallinity shows the enhanced initial efficiency and rate performance. The mechanism of both improvements was also discusssed based on the developed crystal structure of soft carbon based anode materials.

  • https://doi.org/10.14478/ace.2019.1015 인용 PDF KSCI HTML

Effect of Low Temperature Heat Treatment on the Physical and Chemical Properties of Carbon Anode Materials and the Performance of Secondary Batteries (저온 열처리가 탄소 음극재의 물리·화학적 특성 및 이차전지 성능에 미치는 영향)

  • Whang, Tae Kyung;Kim, Ji Hong;Im, Ji Sun;Kang, Seok Chang
    • Applied Chemistry for Engineering
    • /
    • v.32 no.1
    • /
    • pp.83-90
    • /
    • 2021

  • In this study, effects of the physical and chemical properties of low temperature heated carbon on electrochemical behavior as a secondary battery anode material were investigated. A heat treatment at 600 ℃ was performed for coking of petroleum based pitch, and the manufactured coke was heat treated with different heat temperatures at 700~1,500 ℃ to prepare low temperature heated anode materials. The physical and chemical properties of carbon anode materials were studied through nitrogen adsorption and desorption, X-ray diffraction (XRD), Raman spectroscopy, elemental analysis. Also the anode properties of low temperature heated carbon were considered through electrochemical properties such as capacity, initial Coulomb efficiency (ICE), rate capability, and cycle performance. The crystal structure of low temperature (≤ 1500 ℃) heated carbon was improved by increasing the crystal size and true density, while the specific surface area decreased. Electrochemical properties of the anode material were changed with respect to the physical and chemical properties of low temperature heated carbon. The capacity and cycle performance were most affected by H/C atomic ratio. Also, the ICE was influenced by the specific surface area, whereas the rate performance was most affected by true density.

  • https://doi.org/10.14478/ace.2020.1100 인용 PDF KSCI