Dinh Ba Le

High Surface Area V 2 O 5 Aerogel Intercalation Electrodes

Supercritical drying of gels yields amorphous aerogels (ARG) that serve as reversible, high capacity hosts for lithium ion intercalation. We have found that ARG material consists of a highly interconnected solid network that has a surface area up to 450 m2/g and a specific pore volume of 2.3 cm3/g. The material hosts at least per mole of (ARG) as determined by both galvanostatic intermittent titration (GITT) and chemical lithiation (CL) techniques. The equilibrium voltage‐composition curve is identical for both GITT and CL techniques as well. (ARG) has a specific energy in excess of 1600 Wh/kg, the highest ever reported for any vanadium oxide host.

High rate electrodes of V2O5 aerogel

Abstract In the present paper we report on high rate electrodes made from a conventional battery cathode material, vanadium pentoxide. The electrodes were obtained through a sol–gel process by which the active materials were coated in the form of thin, highly porous, layers on appropriate conducting substrates. The composite electrodes are characterized by very short ionic and electronic paths throughout the intercalation compound. Aerogel films deposited on a Hastelloy felt substrate had specific surface areas of 40 m 2 /g with pores of 20–200 nm diameter and wall thicknesses of 10–20 nm. Electrochemical impedance analysis revealed the expected response for intercalation, except that there was no Warburg (diffusion) component. The latter demonstrates that we successfully eliminated one of the primary limitations of intercalation materials, i.e. diffusion in the solid phase, by the design of the composite electrodes.

XAS and electrochemical characterization of lithiated high surface area V2O5 aerogels

Abstract V 2 O 5 aerogel (ARG) has been recently proposed as cathode material for rechargeable lithium batteries. Such a material is amorphous and consists of a highly interconnected solid network with a surface area up to 450 m 2 /g, and a specific pore volume as much as 2.3 cm 3 /g. In a previous paper, it was shown that up to 4 equivalents of lithium per mole of V 2 O 5 aerogel can be inserted by means of chemical or electrochemical lithiation. In the present work, the lithium composition range has been extended. By chemical lithiation (CL) a composition Li 5.8 V 2 O 5 , the highest ever reported for any vanadium oxide host, was achieved. The equilibrium open circuit voltage (OCV)–composition curve of the chemically lithiated aerogel samples showed a wide plateau extending up to 5.8 equivalents of lithium per mole of V 2 O 5 . The surprisingly high OCV has been correlated with the characteristic morphology and structure of the aerogel material by means of X-ray diffraction and absorption and XPS spectroscopies.

Aerogels and xerogels of V{sub 2}O{sub 5} as intercalation hosts

Sol‐gel processing of yields amorphous aerogels (ARG) and xerogels (XRG) that serve as high capacity intercalation hosts for lithium ions. The insertion process is highly reversible in both the aerogel and xerogel form, suggesting that they are attractive for rechargeable lithium batteries and other electrochemical devices.

High surface area V2O5 aerogel intercalation electrodes

Supercritical drying of gels yields amorphous aerogels (ARG) that serve as reversible, high capacity hosts for lithium ion intercalation. We have found that ARG material consists of a highly interconnected solid network that has a surface area up to 450 m2/g and a specific pore volume of 2.3 cm3/g. The material hosts at least per mole of (ARG) as determined by both galvanostatic intermittent titration (GITT) and chemical lithiation (CL) techniques. The equilibrium voltage‐composition curve is identical for both GITT and CL techniques as well. (ARG) has a specific energy in excess of 1600 Wh/kg, the highest ever reported for any vanadium oxide host.

Aerogels and xerogels of V2O5 as intercalation hosts

Sol‐gel processing of yields amorphous aerogels (ARG) and xerogels (XRG) that serve as high capacity intercalation hosts for lithium ions. The insertion process is highly reversible in both the aerogel and xerogel form, suggesting that they are attractive for rechargeable lithium batteries and other electrochemical devices.

Aerogels and Xerogels of V 2 O 5 as Intercalation Hosts

Sol‐gel processing of yields amorphous aerogels (ARG) and xerogels (XRG) that serve as high capacity intercalation hosts for lithium ions. The insertion process is highly reversible in both the aerogel and xerogel form, suggesting that they are attractive for rechargeable lithium batteries and other electrochemical devices.