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Olivine structure LiFePO 4 (LFP) was synthesized via solid state processes, using Li 2 CO 3 , NH 4 H 2 PO 4 , and FeC 2 O 4 ⋅H 2 O and C 12 H 22 O 11 as precursor materials. The effects of calendaring are analyzed in terms of electrochemical performance, cycle life, surface morphology, and ac impedance analysis. The resulting LFP electrode was divided into calendared and uncalendared samples. Under electrochemical impedance testing, the calendared and uncalendared electrodes exhibited a charge transfer resistance of 157.8 Ω and 182.4 Ω, respectively. The calendared electrode also exhibited a higher discharge capacity of about 130 mAh/g at 0.1 compared to a discharge capacity of 120 mAh/g at 0.1 for the uncalendared electrode.

Binder-free Co-Mn composite oxide was successfully deposited at low temperature on a woven substrate through a combination of electroless and electrolytic steps. The principle of the approach was illustrated with cobalt metal and a successful thin film metal oxide formation was supported by CV, XRD and XPS data. The viability of the binder-free Co-Mn oxide electrode was tested as a Li-air battery electrocatalyst and yielded an initial specific capacity of up to 2000 mA h g À1 and survived multiple charge-dischargerecharge cycles. The oxidation time in the electrolytic oxidation-step was found to affect the battery discharge period. In comparison to the conventional polymeric binder methods, the present binder-free method is potentially adaptable to a roll-roll continuous processing approach. Experimental Materials preparationThe thin lm Co-Mn composite oxide catalyst was prepared on a exible woven carbon substrate (Fuel Cell Earth, AvCarbele, 11 ohm cm electrical resistivity, 99.5% carbon content) which is rst

In this paper, investigation on the effect of separator thickness and porosity on the performance of Lithium Iron Phosphate batteries are analyzed. In recent years there have been intensive efforts to improve the performance of the lithium-ion batteries. Separators are important component of lithium-ion batteries since they isolate the electrodes and prevent electrical short-circuits. Separators are also used as an electrolyte reservoir which is used as a medium for ions transfer during charge and discharge. Electrochemical performance of the batteries is highly dependent on the material, structure, and separators used. This paper compares the effects of material properties and the porosity of the separator on the performance of lithium-ion batteries. Four different separators, polypropylene (PP) monolayer and polypropylene/polyethylene/polypropylene (PP/PE/PP) trilayer, with the thickness of 20 μm and 25 μm and porosities of 41%, 45%, 48%, and 50% were used for testing. It was found that PP separator with porosity of 41% and PP/PE/PP separator of 45% porosity perform better compared to other separators.

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