1. |
- Kim, Jae-Kwang, 1978, et al.
(författare)
-
Effect of carbon coating methods on structural characteristics and electrochemical properties of carbon-coated lithium iron phosphate
- 2014
-
Ingår i: Solid State Ionics. - : Elsevier BV. - 0167-2738. ; 262, s. 25-29
-
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.
|
|
2. |
- Manuel, J., et al.
(författare)
-
Electrochemical properties of lithium polymer batteries with doped polyaniline as cathode material
- 2012
-
Ingår i: Materials Research Bulletin. - : Elsevier BV. - 0025-5408. ; 47:10, s. 2815-2818
-
Konferensbidrag (refereegranskat)abstract
- Polyaniline (PAN!) was doped with different lithium salts such as LiPFG and LiClO4 and evaluated as cathode-active material for application in room-temperature lithium batteries. The doped PANT was characterized by FTIR and XPS measurements. In the FTIR spectra, the characteristic peaks of PANT are shifted to lower bands as a consequence of doping, and it is more shifted in the case of PANI doped with LiPFG. The cathodes prepared using PANT doped with LiPF6 and LiClO4 delivered initial discharge capacities of 125 mAh g(-1) and 112 mAh g(-1) and stable reversible capacities of 114 mAh g(-1) and 81 mAh g(-1), respectively, after 10 charge-discharge cycles. The cells were also tested using polymer electrolyte, which delivered highest discharge capacities of 142.6 mAh g(-1) and 140 mAh g(-1) and stable reversible capacities of 117 mAh g(-1) and 122 mAh g(-1) for PANT-LiPF6 and PANI-LiClO4, respectively, after 10 cycles. The cathode prepared with LiPFG doped PANT shows better cycling performance and stability as compared to the cathode prepared with LiClO4 doped PANT using both liquid and polymer electrolytes.
|
|