• 한국전기화학회:학술대회논문집
• /
• 2004.10a
• /
• pp.28-28
• /
• 2004

• 한국전기화학회:학술대회논문집
• /
• 2001.10a
• /
• pp.37-37
• /
• 2001

• 한국전기화학회:학술대회논문집
• /
• 2003.04a
• /
• pp.26-26
• /
• 2003

• Bulletin of the Korean Chemical Society
• /
• v.19 no.2
• /
• pp.261-263
• /
• 1998

• Bulletin of the Korean Chemical Society
• /
• v.34 no.3
• /
• pp.717-718
• /
• 2013

• Journal of the Korean Electrochemical Society
• /
• v.13 no.1
• /
• pp.19-33
• /
• 2010

The surface film, which is formed on graphite negative electrodes during the initial charging, is a key component in lithium secondary batteries. The battery reactions are strongly affected by the nature of the surface film. It is thus very important to understand the physicochemical properties of the surface film. On the other hand, the surface film formation is a very complicated interfacial phenomenon occurring at the graphite/electrolyte interface. In studies on electrode surfaces in lithium secondary batteries, in-situ experimental techniques are very important because the surface film is highly reactive and unstable in the air. In this respect electrochemical atomic force microscopy (ECAFM) is a useful tool for direct visualizing electrode/solution interfaces at which various electrochemical reactions occur under potential control. In the present review, mechanism of surface film formation and its correlation with electrolyte are summarized on the basis of in-situ ECAFM studies for understanding of the nature of the surface film on graphite negative electrodes.

• Journal of the Korean Electrochemical Society
• /
• v.3 no.3
• /
• pp.173-177
• /
• 2000

The synthetic carbon was coated with tin oxide and copper by fluidized-bed chemical vapor deposition method. $(CH_3)_4Sn\;and\;Cu(hfac)_{2s}$ were employed as the metallic organic precursor, respectively. The modified synthetic carbons were used for lithium secondary battery anode to investigate their coating effects on electrochemical characteristics as alternative anode materials for lithium secondary batteries. The electrode which prepared by the synthetic carbons(MCMB) coated with tin oxide gave the higher capacity than that of raw material. Their capacity decreased with the progress of cycling possibly due to severe volume changes. But the cyclability was improved by coating with copper on the surface of the tin oxide coated carbon, which plays an important role as an inactive matrix buffering volume changes.

• KEPCO Journal on Electric Power and Energy
• /
• v.1 no.1
• /
• pp.33-38
• /
• 2015

Energy storage systems (ESSs) have been utilized widely in the world to optimize the power operation system and to improve the power quality. As lithium secondary batteries are the main power supplier for ESSs, it is very important to predict its cycle and power degradation behavior. In particular, the power, one of the hardest electrochemical properties to measure, needs lots of resources such as time and facilities. Due to these difficulties, computer modelling of lithium secondary batteries is applied to predict the DC-IR and power value during charging and discharging as a function of state of charge (SOC) by using pulse-based measurement methods. Moreover, based on the hybrid pulse power characteristics (HPPC) and J-Pulse (JEVS D 713, Japan Electric Vehicle Association Standards) methods, their electrochemical properties are also compared and discussed.

• The Journal of the Institute of Internet, Broadcasting and Communication
• /
• v.23 no.4
• /
• pp.171-176
• /
• 2023

In the modern society of the 21st century, portable electronic products using secondary batteries are continuously becoming lightweight and miniaturized. And along with this trend, we are active in the era of the Fourth Industrial Revolution, where we collect and share information in our daily lives using wearable electronic devices. Therefore, the role of secondary batteries that can be recharged while using small home appliances and digital devices is increasingly important. Along with this increase, secondary battery performance tests require various test methods such as characteristics, lifespan, failure diagnosis, and recycling. In addition, the construction of a battery test system to ensure the safety and proper functioning of the battery, along with guidelines and correct basic knowledge are being considered. Therefore, in this paper, we will examine the characteristics of the secondary battery Li-ion battery according to the charging and discharging scenarios directly connected to the performance of the battery.

• The Transactions of the Korean Institute of Electrical Engineers C
• /
• v.49 no.6
• /
• pp.328-334
• /
• 2000

A lithium ion secondary battery using carbon as a negative electrode has been developed. Further improvements to increase the cell capacity are expected by modifying the structure of the carbonaceous material. There are hopes for the development of large capacity lithium ion secondary batteries with long cycle, high energy density, high power density, and high energy efficiency. In the present paper, needle cokes from petroleum were examined as an anode of lithium ion secondary battery. Petroleum cokes, MCL(Molten Caustic Leaching) treated in Korea Institute Energy Research, were carbonized at various temperatures of 0, 500, 700, $19700^{\circ}C$ at heating rate of $2^{\circ}C$/min for lh. The electrolyte was used lM liPF6 EC/DEC (1:1). The voltage range of charge & discharge was 0.0V(0.05V) ~ 2.0V. The treated petroleum coke at $700^{\circ}C$ had an initial capacity over 560mAh.g which beyond the theoretical maximum capacity, 372mAh/g for LiC6. This phenomena suggests that carbon materials with disordered structure had higher cell capacity than that the graphitic carbon materials.