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Engineering topics

Datta, Moni Kanchan

Publications and source records attributed to Datta, Moni Kanchan.

Electrospinning of PVdF-HFP: novel composite polymer electrolytes (CPES) with enhanced ionic conductivities for lithium-sulfur batteries

The invention relates to lithium ion batteries and, more particularly, to lithium ion conducting composite polymer electrolyte separators. The separators include a nanofiber mat composed of electrospun nanofibers. The nanofibers include a polymer having one or more polar halogen groups, a lithium-containing solid or liquid electrolyte and nanoparticle filler. The polymer, electrolyte and filler are combined to form a solution that is subjected to the electro-spinning process to produce electrospun nanofibers in the form of the mat.

Kumta, Prashant N.↗

Cathodes and electrolytes for rechargeable magnesium batteries and methods of manufacture

The invention relates to Chevrel-phase materials and methods of preparing these materials utilizing a precursor approach. The Chevrel-phase materials are useful in assembling electrodes, e.g., cathodes, for use in electrochemical cells, such as rechargeable batteries. The Chevrel-phase materials have a general formula of Mo 6 Z 8 (Z=sulfur) or Mo 6 Z 1 8-yZ 2 y (Z 1 =sulfur; Z 2 =selenium), and partially cuprated Cu 1 Mo 6 S 8 as well as partially de-cuprated Cu 1-x Mg x Mo 6 S 8 and the precursors have a general formula of M x Mo 6 Z 8 or M x Mo 6 Z 1 8-yZ 2 y , M=Cu. The cathode containing the Chevrel-phase material in accordance with the invention can be combined with a magnesium-containing anode and an electrolyte.

Kumta, Prashant N.↗

High capacity, air-stable, structurally isomorphous lithium alloy multilayer porous foams

The invention relates to composite multilayer lithium ion battery anodes that include a porous metal alloy foam, and a lithium ion conductor coating applied to the metal alloy foam. The metal alloy foam can include structurally isomorphous alloys of lithium and, optionally, lithium and magnesium. The lithium ion conductor coating can include ternary lithium silicate, such as, lithium orthosilicate. Lithium ions from the ternary lithium silicate may be deposited within the pores of the metal alloy foam. Optionally, the lithium ion conductor coating may include a dopant. The dopant can include one or more of magnesium, calcium, vanadium, niobium and fluorine, and mixtures and combinations thereof.

Kumta, Prashant N.↗

Non-noble metal based electro-catalyst compositions for proton exchange membrane based water electrolysis and methods of making

The invention provides electro-catalyst compositions for an anode electrode of an acid mediated proton exchange membrane-based water electrolysis system. The compositions include a noble metal component selected from the group consisting of iridium oxide, ruthenium oxide, rhenium oxide and mixtures thereof, and a non-noble metal component selected from the group consisting of tantalum oxide, tin oxide, niobium oxide, titanium oxide, tungsten oxide, molybdenum oxide, yttrium oxide, scandium oxide, cooper oxide, zirconium oxide, nickel oxide and mixtures thereof. Further, the non-noble metal component can include a dopant. The dopant can be at least one element selected from Groups III, V, VI and VII of the Periodic Table. The compositions can be prepared using any solution based methods involving a surfactant approach or a sol gel approach. Further, the compositions are prepared using noble metal and non-noble metal precursors. Furthermore, a thin film containing the compositions can be deposited onto a substrate to form the anode electrode.

Kumta, Prashant N.↗

Cathodes and electrolytes for rechargeable magnesium batteries and methods of manufacture

The invention relates to Chevrel-phase materials and methods of preparing these materials utilizing a precursor approach. The Chevrel-phase materials are useful in assembling electrodes, e.g., cathodes, for use in electrochemical cells, such as rechargeable batteries. The Chevrel-phase materials have a general formula of Mo6Z8 and the precursors have a general formula of MxMo6Z8. The cathode containing the Chevrel-phase material in accordance with the invention can be combined with a magnesium-containing anode and an electrolyte.

Kumta, Prashant N.↗

Constitutional under-potential plating (CUP) – New insights for predicting the morphological stability of deposited lithium anodes in lithium metal batteries

Lithium (Li) cycling in lithium metal batteries (LMBs) inevitably witnesses a non-planar Li/electrolyte interface (cellular/dendritic microstructure) affecting the performance, safety and reliability of LMBs. Herein, the “constitutional under-potential plating” (CUP) concept is presented for the first time to understand the evolution, formation and predict the morphological stability/instability of the Li/electrolyte interface. Here, the CUP condition, a measure of the driving force for interface perturbation, occurs when the true potential gradient at the interface is smaller than the equilibrium electrodeposition potential gradient at the Li/electrolyte interface resulting in the electrolyte ahead of the Li-electrolyte interface to be in an under-potential state. Detailed CUP criterion calculations conducted herein establishes the relationship of battery operating conditions (e.g. current density, potential gradient) with the electrolyte properties (e.g. Li-ion transference number and diffusion coefficient) predicting the morphological stability condition at the interface. In addition to the driving force for interface perturbation, the capillarity effect or the Gibbs Thomson effect, a measure of the resistance to perturbation of the perturbed interface is discussed for understanding the influence of interfacial energy/adhesion energy between the current collector and the deposited Li on the overall morphological stability of the Li/electrolyte interface, a critical criterion for the unwanted dendritic morphology.

25 ENERGY STORAGE↗