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- Kim, Jae-Kwang, 1978, et al.
(författare)
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2,3,6,7,10,11-Hexamethoxytriphenylene (HMTP): A new organic cathode material for lithium batteries
- 2012
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Ingår i: Electrochemistry Communications. - : Elsevier BV. - 1388-2481. ; 21:1, s. 50-53
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Tidskriftsartikel (refereegranskat)abstract
- We propose a new organic cathode material for rechargeable lithium battery applications: 2,3,6,7,10,11-hexamethoxytriphenylene (HMTP). HMTP is composed of six methoxy functional groups substituted onto a central triphenylene moiety. The cell, incorporating 40 wt.% of organic cathode material, exhibits full specific capacity at current densities up to 3 C. The main advantage of HMTP as organic cathode material lies in a stable cell performance and negligible self discharge, even though the capacity is lower, similar to 66 mAh/g, compared to other organic cathode materials. Cells with the HMTP cathode showed >95% retention of the initial discharge capacity after 50 cycles at 1 C and self-discharge was not observed during a full month of open circuit voltage measurements. The latter is due to the fact that the nature of the HMTP radical is fundamentally different from other organic cathode materials' radicals.
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| 2. |
- Kim, Jae-Kwang, 1978, et al.
(författare)
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Effect of carbon coating methods on structural characteristics and electrochemical properties of carbon-coated lithium iron phosphate
- 2014
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Ingår i: Solid State Ionics. - : Elsevier BV. - 0167-2738. ; 262, s. 25-29
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Tidskriftsartikel (refereegranskat)abstract
- The potential of LiFePO4 as cathode material has not been fully exploited due to its intrinsic poor electronic and ionic conductivities. Attempts have been made to improve these properties of which coating of the active carbon on the particle surface is the most viable method so far. Phase-pure LiFePO4 and two LiFePO4/C composites were synthesized by mechanical activation process employing two different methods: (i) direct addition of acetylene black carbon and (ii) addition of sucrose as carbon precursor. The samples were well characterized by various techniques like elemental analysis, Brunauer-Emmett-Teller (BET) method, scanning electron microscopy (SEM), X-ray powder diffraction (XRD), and Raman spectroscopy to establish their composition, morphology, particle size and surface area. The structure of these samples is investigated as olivine structure space group Prima by X-ray powder diffraction. Transmission electron microscopy (TEM) confirms that the carbon nanocoating on the LiFePO4 particles has no visible dislocations and fractures. The electrochemical performance of LiFePO4/C is significantly affected by the nature of the carbon nanocoating, which in turn is affected by the choice of synthesis method.
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