Abstract: Disclosed is a facile and cost effective method of producing nano silicon powder or graphene-doped silicon nano powder having a particle size smaller than 100 nm. The method comprises: (a) preparing a silicon precursor/graphene nano composite; (b) mixing the silicon precursor/graphene nano composite with a desired quantity of magnesium; (c) converting the silicon precursor to form a mixture of graphene-doped silicon and a reaction by-product through a thermal and/or chemical reduction reaction; and (d) removing the reaction by-product from the mixture to obtain graphene-doped silicon nano powder.

Abstract: An apparatus includes an interface and a circuit. The interface may be configured to generate a read signal that carries read data from a memory channel. The circuit may be configured to (i) modify the read signal with a de-emphasis on each pull up of the read signal and a pre-emphasis on each pull down of the read signal and (ii) transfer the read signal as modified to a memory controller.

Abstract: An apparatus includes an interface and a circuit. The interface may be configured to generate a memory signal that carries read data from a memory channel. The circuit may be configured to modify a read signal that transfers the read data across a read line to a memory controller. A filter may delay the memory signal to generate a delayed signal. A driver generally amplifies the memory signal to generate the read signal. The driver may modify the read signal with a de-emphasis on each pull up of the memory signal and a pre-emphasis on each pull down of the memory signal based on the delayed signal.

Abstract: A method of operating a lithium-ion cell comprising (a) a cathode comprising a carbon or graphitic material having a surface area to capture and store lithium thereon; (b) an anode comprising an anode active material; (c) a porous separator disposed between the two electrodes; (d) an electrolyte in ionic contact with the two electrodes; and (e) a lithium source disposed in at least one of the two electrodes to obtain an open circuit voltage (OCV) from 0.5 volts to 2.8 volts when the cell is made; wherein the method comprises: (A) electrochemically forming the cell from the OCV to either a first lower voltage limit (LVL) or a first upper voltage limit (UVL), wherein the first LVL is no lower than 0.1 volts and the first UVL is no higher than 4.6 volts; and (B) cycling the cell between a second LVL and a second UVL.

Abstract: An apparatus includes an interface and a circuit. The interface may be configured to generate a memory signal that carries read data from a memory channel. The circuit may be configured to modify a read signal that transfers the read data across a read line to a memory controller. A filter may delay the memory signal to generate a delayed signal. A driver generally amplifies the memory signal to generate the read signal. The driver may modify the read signal with a de-emphasis on each pull up of the memory signal and a pre-emphasis on each pull down of the memory signal based on the delayed signal.

Abstract: A process for producing a separator-electrolyte layer for use in a lithium battery, comprising: (a) providing a porous separator; (b) providing a quasi-solid electrolyte containing a lithium salt dissolved in a first liquid solvent up to a first concentration no less than 3 M; and (c) coating or impregnating the separator with the electrolyte to obtain the separator-electrolyte layer with a final concentration?the first concentration so that the electrolyte exhibits a vapor pressure less than 0.01 kPa when measured at 20° C., a vapor pressure less than 60% of that of the first liquid solvent alone, a flash point at least 20 degrees Celsius higher than a flash point of the first liquid solvent alone, a flash point higher than 150° C., or no detectable flash point. A battery using such a separator-electrolyte is non-flammable and safe, has a long cycle life, high capacity, and high energy density.

Abstract: A separator-electrolyte layer product for use in a lithium battery, comprising: (a) a porous thin-film separator selected from a porous polymer film, a porous mat, fabric, or paper made of polymer or glass fibers, or a combination thereof, wherein the separator has a thickness less than 500 ?m; and (b) a non-flammable quasi-solid electrolyte containing a lithium salt dissolved in a liquid solvent up to a concentration no less than 3 M; wherein the porous thin-film separator is coated with the quasi-solid electrolyte so that the layer product exhibits a vapor pressure less than 0.01 kPa when measured at 20° C., a vapor pressure less than 60% of the vapor pressure of the liquid solvent alone, a flash point at least 20 degrees Celsius higher than a flash point of the first liquid solvent alone, a flash point higher than 150° C., or no detectable flash point.

Abstract: An apparatus includes a first circuit and a second circuit. The first circuit may be configured to (a) buffer write signals presented on a data bus connected between a memory channel and a memory controller, (b) buffer read signals presented on the data bus and (c) condition the write signals. The conditioning may be implemented by (i) converting the write signals to a first differential write signal on a first differential write line and a second differential write signal on a second differential write line and (ii) connecting (a) a negative impedance and (b) a combined resistive and capacitive load between the first and second differential write lines. The second circuit may be configured to (a) convert the first and the second differential write signals to a single-ended write signal and (b) present the single-ended write signal to the data bus.

Abstract: A process for producing a highly oriented graphene film (HOGF), comprising: (a) preparing a graphene oxide (GO) dispersion having GO sheets dispersed in a fluid medium; (b) dispensing and depositing the dispersion onto a surface of a supporting substrate to form a layer of GO, wherein the dispensing and depositing procedure includes subjecting the dispersion to an orientation-inducing stress; (c) removing the fluid medium to form a dried layer of GO having an inter-plane spacing d002 of 0.4 nm to 1.2 nm; (d) slicing the dried layer of GO into multiple pieces of dried GO and stacking at least two pieces of dried GO to form a mass of multiple pieces of GO; and (f) heat treating the mass under an optional first compressive stress to produce the HOGF at a first heat treatment temperature higher than 100° C. to an extent that an inter-plane spacing d002 is decreased to a value less than 0.4 nm.

Abstract: The present invention provides a process for producing a graphene-enhanced anode active material for use in a lithium battery. The process comprises (a) providing a continuous film of a graphene material into a deposition zone; (b) introducing vapor or atoms of a precursor anode active material into the deposition zone, allowing the vapor or atoms to deposit onto a surface of the graphene material film to form a sheet of an anode active material-coated graphene material; and (c) mechanically breaking this sheet into multiple pieces of anode active material-coated graphene; wherein the graphene material is in an amount of from 0.1% to 99.5% by weight and the anode active material is in an amount of at least 0.5% by weight, all based on the total weight of the graphene material and the anode active material combined.

Abstract: A magnesium-ion cell comprising (a) a cathode comprising a carbon or graphitic material as a cathode active material having a surface area to capture and store magnesium thereon, wherein the cathode forms a meso-porous structure having a pore size from 2 nm to 50 nm and a specific surface area greater than 50 m2/g; (b) an anode comprising an anode current collector alone or a combination of an anode current collector and an anode active material; (c) a porous separator disposed between the anode and the cathode; (d) electrolyte in ionic contact with the anode and the cathode; and (e) a magnesium ion source disposed in the anode to obtain an open circuit voltage (OCV) from 0.5 volts to 3.5 volts when the cell is made.

Abstract: A lithium-ion cell comprising: (A) a cathode comprising graphene as the cathode active material having a surface area to capture and store lithium thereon and wherein said graphene cathode is meso-porous having a specific surface area greater than 100 m2/g; (B) an anode comprising an anode active material for inserting and extracting lithium, wherein the anode active material is mixed with a conductive additive and/or a resin binder to form a porous electrode structure, or coated onto a current collector in a coating or thin film form; (C) a porous separator disposed between the anode and the cathode; (D) a lithium-containing electrolyte in physical contact with the two electrodes; and (E) a lithium source disposed in at least one of the two electrodes when the cell is made. This new Li-ion cell exhibits an unprecedentedly high energy density.

Abstract: The present invention provides a battery or supercapacitor current collector which is prelithiated. The prelithiated current collector comprises: (a) an electrically conductive substrate having two opposed primary surfaces, and (b) a mixture layer of carbon (and/or other stabilizing element, such as B, Al, Ga, In, C, Si, Ge, Sn, Pb, As, Sb, Bi, Te, or a combination thereof) and lithium or lithium alloy coated on at least one of the primary surfaces, wherein lithium element is present in an amount of 1% to 99% by weight of the mixture layer. This current collector serves as an effective and safe lithium source for a wide variety of electrochemical energy storage cells, including the rechargeable lithium cell (e.g. lithium-metal, lithium-ion, lithium-sulfur, lithium-air, lithium-graphene, lithium-carbon, and lithium-carbon nanotube cell) and the lithium ion based supercapacitor cell (e.g, symmetric ultracapacitor, asymmetric ultracapacitor, hybrid supercapacitor-battery, or lithium-ion capacitor).

Abstract: This invention provides a portable computing device powered by a surface-mediated cell (SMC)-based power source, the portable device comprising a computing hardware sub-system and a rechargeable power source electrically connected to the hardware and providing power thereto, wherein the power source contains at least a surface-mediated cell. The portable computing device is selected from a laptop computer, a tablet, an electronic book (e-book), a smart phone, a mobile phone, a digital camera, a hand-held calculator or computer, or a personal digital assistant.

Abstract: A rechargeable lithium cell comprising a cathode having a cathode active material, an anode having an anode active material, a porous separator electronically separating the anode and the cathode, a non-flammable quasi-solid electrolyte in contact with the cathode and the anode, wherein the electrolyte contains a lithium salt dissolved in a first organic liquid solvent with a concentration sufficiently high so that the electrolyte exhibits a vapor pressure less than 0.01 kPa when measured at 20° C., a flash point at least 20 degrees Celsius higher than the flash point of the first organic liquid solvent alone, a flash point higher than 150° C., or no flash point. This battery cell is non-flammable and safe, has a long cycle life, high capacity, and high energy density.

Abstract: An energy storage stack of at least two surface-mediated cells (SMCs) internally connected in parallel or in series. The stack includes: (A) At least two SMC cells, each consisting of (i) a cathode comprising a porous cathode current collector and a cathode active material; (ii) a porous anode current collector; and (iii) a porous separator disposed between the cathode and the anode; (B) A lithium-containing electrolyte in physical contact with all the electrodes, wherein the cathode active material has a specific surface area no less than 100 m2/g in direct physical contact with the electrolyte to receive lithium ions therefrom or to provide lithium ions thereto; and (C) A lithium source. This new-generation energy storage device exhibits the highest power densities of all energy storage devices, much higher than those of all the lithium ion batteries, lithium ion capacitors, and supercapacitors.

Abstract: A one-step (direct graphitization) process for producing a graphitic film, comprising directly feeding a precursor polymer film, without going through a carbonization step, to a graphitization zone preset at a graphitization temperature no less than 2,200° C. for a period of residence time sufficient for converting the precursor polymer film to a porous graphitic film having a density from 0.1 g/cm3 to 1.5 g/cm3 and retreating the porous graphitic film from the graphitization zone. Preferably, the precursor polymer film is selected from the group consisting of polyimide, polyamide, phenolic resin, polyoxadiazole, polybenzoxazole, polybenzobisoxazole, polythiazole, polybenzothiazole, polybenzobisthiazole, poly(p-phenylene vinylene), polybenzimidazole, polybenzobisimidazole, polyacrylonitrile, and combinations thereof.

Abstract: Provided is a cathode (positive electrode) of a lithium battery and a process for producing this cathode. The electrode comprises a cathode active material-coated graphene sheet and the graphene sheet has two opposed parallel surfaces, wherein at least 50% area (preferably greater than 80%) of one of the two surfaces is coated with a cathode active material coating. The graphene material is in an amount of from 0.1% to 99.5% by weight and the cathode active material is in an amount of at least 0.5% by weight (preferably greater than 80% and more preferably greater than 90%), all based on the total weight of the graphene material and the cathode active material combined. The cathode active material is preferably an inorganic material, an organic or polymeric material, a metal oxide/phosphate/sulfide, or a combination thereof. Also provided is a lithium battery, including a lithium-ion, lithium-metal, or lithium-sulfur battery.

Abstract: A process for producing a bulk highly oriented graphene structure, comprising: (a) preparing a graphene oxide dispersion having graphene oxide (GO) sheets dispersed in a fluid medium; (b) dispensing and depositing the dispersion onto a surface of a supporting substrate to form a layer of GO, wherein the dispensing and depositing procedure includes subjecting the dispersion to an orientation-inducing stress; (c) removing the fluid medium to form a dried layer of GO having an inter-plane spacing d002 of 0.4 nm to 1.2 nm; (d) slicing the dried layer of GO into multiple pieces of dried GO and stacking at least two pieces of dried GO to form a mass of multiple pieces of GO; and (f) heat treating the mass under an optional first compressive stress to produce the highly oriented graphene structure at a first heat treatment temperature higher than 100° C. to an extent that an inter-plane spacing d002 is decreased to a value less than 0.4 nm.

Abstract: A rechargeable lithium metal or lithium-ion cell comprising a cathode having a cathode active material and/or a conductive supporting structure, an anode having an anode active material and/or a conductive supporting nano-structure, a porous separator electronically separating the anode and the cathode, a highly concentrated electrolyte in contact with the cathode active material and the anode active material, wherein the electrolyte contains a lithium salt dissolved in an ionic liquid solvent with a concentration greater than 3 M. The cell exhibits an exceptionally high specific energy, a relatively high power density, a long cycle life, and high safety with no flammability.