Abstract:
A method for manufacturing an electrode for a lithium-based battery by electrophoretic deposition is provided. The method includes: mixing particles with graphene oxide and a binder in a solution, the particles including a material selected from silicon, silicon oxide, silicon alloys, tin, tin oxide, sulfur, lithium manganese oxide, lithium cobalt oxide, lithium nickel oxide, lithium nickel manganese oxide, and lithium nickel manganese cobalt oxide. The method further includes applying a potential between a current collector and a counter electrode immersed in the solution to deposit a coating of a combination of the particles, at least partially reduced graphene oxide, and binder onto the current collector. The method still further includes drying the coated current collector.
Abstract:
In an example of a method for making a sulfur-based positive electrode active material, a carbon layer is formed on a sacrificial nanomaterial. The carbon layer is coated with titanium dioxide to form a titanium dioxide layer. The sacrificial nanomaterial is removed to form a hollow material including a hollow core surrounded by a carbon and titanium dioxide double shell. Sulfur is impregnated into the hollow core.
Abstract:
In an example of a method for forming a catalyst, a polymeric solution including a platinum group metal (PGM) is exposed to electrospinning to form carbon-based nanofibers containing PGM nanoparticles therein. An outer surface of the carbon-based nanofibers containing the PGM nanoparticles is coated with a metal oxide or a metal oxide precursor. The carbon-based nanofibers are selectively removed to form metal oxide nanotubes having PGM nanoparticles retained within a hollow portion thereof.
Abstract:
A catalytic converter includes a catalyst. The catalyst includes a support, platinum group metal (PGM) particles dispersed on the support, and a barrier formed on the support. The barrier is disposed between a first set of the PGM particles and a second set of the PGM particles to suppress aging of the PGM particles.
Abstract:
An electrode material for an electrochemical cell, such as a lithium ion battery or a lithium sulfur battery, is provided. The electrode may be a negative anode. The electrode material comprises a composite comprising a porous matrix comprising a carbonized material. The electrode material further comprises a plurality of silicon particles homogeneously dispersed in the porous matrix of carbonized material. Each silicon particle of the plurality has an average particle diameter of greater than or equal to about 5 nanometers and less than or equal to about 20 micrometers.
Abstract:
In an example method, a transition metal precursor is selected so its transition metal has a diffusion rate that is slower than a diffusion rate of silicon. An aqueous mixture is formed by dissolving the precursor in an aqueous medium, and adding silicon particles to the medium. The mixture is exposed to a hydroxide, which forms a product including the silicon particles and a transition metal hydroxide precipitate. The product is dried. In an inert or reducing environment, silicon atoms of the silicon particles in the dried product are caused to diffuse out of, and form voids in and/or at a surface of, the particles. At least some silicon atoms react with the transition metal hydroxide in the dried product to form i) a SiOx (0
Abstract:
A negative electrode includes an active material. The active material includes a silicon-based core and a two-dimensional, layered mesoporous carbon coating in continuous contact with the silicon-based core. The two-dimensional, layered mesoporous carbon coating is capable of expanding and contracting with the silicon-based core. The negative electrode also includes a binder.
Abstract:
Use of a flexible, nonconductive, porous, and thermally tolerant ceramic material as a separator in a lithium-ion battery or lithium-sulfur battery is described. The separator can be made of aluminum oxide and provides excellent mechanical and thermal properties that prevent wear and puncture of the separator caused by particles removed from the electrodes during the charging and discharging process. The separator is designed to mitigate effects of melt shrinkage and facilitate the lithium ion transport, in contrast to separators that include a polymeric material, thus preventing short-circuiting between the positive and the negative electrode. Improved wetting and filling of the separator with electrolyte solution are provided, for improved rate capability of the battery (fast charging and discharging). The separator further reduces the potential for thermal runaway in Li batteries.
Abstract:
Porous, amorphous lithium storage materials and a method for making these materials are disclosed herein. In an example of the method, composite particles of a lithium storage material in an amorphous phase and a material that is immiscible with the lithium storage material are prepared. Phase separation is induced within the composite particles to precipitate out the amorphous phase lithium storage material and form phase separated composite particles. The immiscible material is chemically etched from the phase separated composite particles to form porous, amorphous lithium storage material particles.
Abstract:
Use of a flexible, nonconductive, porous, and thermally tolerant ceramic material as a separator in a lithium-ion battery or lithium-sulfur battery is described. The separator can be made of aluminum oxide and provides excellent mechanical and thermal properties that prevent wear and puncture of the separator caused by particles removed from the electrodes during the charging and discharging process. The separator is designed to mitigate effects of melt shrinkage and facilitate the lithium ion transport, in contrast to separators that include a polymeric material, thus preventing short-circuiting between the positive and the negative electrode. Improved wetting and filling of the separator with electrolyte solution are provided, for improved rate capability of the battery (fast charging and discharging). The separator further reduces the potential for thermal runaway in Li batteries.