Patent classifications
C01B32/21
Anode active material, preparation method therefor, and nonaqueous lithium secondary battery comprising same anode active material, and preparation method therefor
The present invention relates to an anode active material, a nonaqueous lithium secondary battery comprising the same, and a preparation method therefor, and the purpose of the present invention is to improve high-rate charging characteristics without deterioration of charging and discharging efficiency and lifetime characteristics when applying an amorphous carbon coating layer as the anode active material of the nonaqueous lithium secondary battery, wherein the amorphous carbon coating layer comprising MoPx particles composed of MoP and MoP.sub.2 is formed on the surface of a carbon-based material, thereby reducing resistance when intercalating lithium ions into the surface of the carbon-based material, and improving reactivity and structural stability of the surface. The anode active material according to the present invention comprises a carbon-based material, and an amorphous carbon coating layer comprising MoPx particles composed of MoP and MoP.sub.2 formed on the surface of the carbon-based material.
GRAPHITE COMPOSITIONS AND USES IN BATTERY TECHNOLOGY
The present disclosure relates to compositions comprising at least one carbonaceous particulate material comprised of synthetic graphite particles having a BET specific surface area (SSA) of equal to or less than 4 m.sup.2/g, and further comprising between about 5 and about 75% (w/w) of at least one carbonaceous particulate material comprised of natural graphite particles coated with non-graphitic carbon and having a BET SSA of equal to or less than 8 m.sup.2/g. Such compositions are particularly useful as active material for negative electrodes in, e.g., lithium-ion batteries and the like in view of their overall favorable electrochemical properties, particularly for automotive and energy storage applications. The present disclosure also relates to the use of said non-graphitic carbon-coated natural graphite particles for preparing compositions that are suitable for being used as an active material in a negative electrode of, e.g., a lithium ion battery. The non-graphitic carbon-coated natural graphite particles described herein are also useful as a carbonaceous additive to increase, e.g., the energy density and charge rate performance of a lithium-ion battery while maintaining the power density of the cell compared to a cell with an anode absent the carbonaceous additive.
GLOBULAR CARBON-BASED ANODE ACTIVE MATERIAL, METHOD FOR MANUFACTURING SAME, AND ANODE AND LITHIUM SECONDARY BATTERY COMPRISING SAME
A spheronized carbonaceous negative electrode active material and a method of preparing a spheronized carbonaceous negative electrode active material, which has an average particle diameter (D.sub.50) of 8.5-10.5 μm, a minimum particle diameter (D.sub.min) of 2.3 μm or more, and a tap density of 1.00-1.20 g/cc.
2D MATERIAL MEMBRANE WITH IONIC SELECTIVITY
There is provided a multi-layered membrane comprising a top layer, a bottom layer, and a spacer layer; wherein said spacer layer is interposed between said top layer and said bottom layer; wherein said top layer, said bottom layer and said spacer layer are each independently composed of one or more selective layers, each selective layer comprising a 2D material; wherein said spacer layer comprises at least one channel for receiving a fluid; wherein said bottom layer comprises a hole with an area in the range of 1 μm.sup.2 to 1 mm.sup.2; and wherein said hole is capable of being in fluid communication with said at least one channels of said spacer layer.
There is also provided a method to synthesize the top layer of a multi-layered membrane as disclosed herein, methods for separating a plurality of ions or molecules in a fluid stream, a device comprising a multi-layered membrane as disclosed herein, and use of the method or the device as disclosed herein in osmotic power generation.
2D MATERIAL MEMBRANE WITH IONIC SELECTIVITY
There is provided a multi-layered membrane comprising a top layer, a bottom layer, and a spacer layer; wherein said spacer layer is interposed between said top layer and said bottom layer; wherein said top layer, said bottom layer and said spacer layer are each independently composed of one or more selective layers, each selective layer comprising a 2D material; wherein said spacer layer comprises at least one channel for receiving a fluid; wherein said bottom layer comprises a hole with an area in the range of 1 μm.sup.2 to 1 mm.sup.2; and wherein said hole is capable of being in fluid communication with said at least one channels of said spacer layer.
There is also provided a method to synthesize the top layer of a multi-layered membrane as disclosed herein, methods for separating a plurality of ions or molecules in a fluid stream, a device comprising a multi-layered membrane as disclosed herein, and use of the method or the device as disclosed herein in osmotic power generation.
High functionalization density graphene
Carbon-based materials, and associated methods and articles, are generally provided. In some embodiments, a carbon-based material comprises a carbon-based portion and a functional group bonded to the carbon-based portion. The functional group may be capable of forming a reversible covalent bond with a species. Carbon may make up greater than or equal to 30 wt % of the carbon-based portion. The carbon-based portion may comprise graphene, and a ratio of a total number of functional groups in a plurality of functional groups bonded to the graphene to a total number of carbon atoms in the plurality of carbon atoms of the graphene may be greater than or equal to 1:50. The carbon-based portion may comprise graphene, and greater than or equal to 70% of the graphene sheets may be spaced apart from their nearest neighbors by a distance of greater than or equal to 10 Å. A method may comprise applying a voltage to a carbon-based material. The voltage may be applied in the presence of a combination of solvents comprising a dissolved species. The combination of solvents may comprise a solvent stable at voltages of greater than or equal to −3.15 V and less than or equal to −2.2 V and/or may comprise a solvent with a surface tension within 25% of a surface tension of the carbon-based material. The voltage may be a decreasing voltage that decreases at a rate of greater than or equal to 2 μV/s and less than or equal to 40 μV/s and has a value of greater than or equal to −2.2 V and less than or equal to −3.15 V at at least one point in time.
High functionalization density graphene
Carbon-based materials, and associated methods and articles, are generally provided. In some embodiments, a carbon-based material comprises a carbon-based portion and a functional group bonded to the carbon-based portion. The functional group may be capable of forming a reversible covalent bond with a species. Carbon may make up greater than or equal to 30 wt % of the carbon-based portion. The carbon-based portion may comprise graphene, and a ratio of a total number of functional groups in a plurality of functional groups bonded to the graphene to a total number of carbon atoms in the plurality of carbon atoms of the graphene may be greater than or equal to 1:50. The carbon-based portion may comprise graphene, and greater than or equal to 70% of the graphene sheets may be spaced apart from their nearest neighbors by a distance of greater than or equal to 10 Å. A method may comprise applying a voltage to a carbon-based material. The voltage may be applied in the presence of a combination of solvents comprising a dissolved species. The combination of solvents may comprise a solvent stable at voltages of greater than or equal to −3.15 V and less than or equal to −2.2 V and/or may comprise a solvent with a surface tension within 25% of a surface tension of the carbon-based material. The voltage may be a decreasing voltage that decreases at a rate of greater than or equal to 2 μV/s and less than or equal to 40 μV/s and has a value of greater than or equal to −2.2 V and less than or equal to −3.15 V at at least one point in time.
NEGATIVE ELECTRODE MATERIAL AND PREPARATION METHOD THEREFOR, AND LITHIUM-ION BATTERY
The present application provides a negative electrode material, a preparation method thereof, and a lithium ion battery. The negative electrode material comprises a first graphite core and a composite coating layer coated on the first graphite core. The composite coating layer comprises a second graphite inner layer formed on the surface of the first graphite core and an amorphous carbon outer layer formed on the surface of the second graphite inner layer. The second graphite inner layer is graphite microcrystal. The preparation method comprises: mixing the first graphite and the second graphite and performing the coating treatment to obtain the first graphite coated with the second graphite, wherein the second graphite is graphite microcrystals; and making the first graphite coated with the second graphite, coated with carbon, to obtain the negative electrode material. The negative electrode material provided in the present application utilizes the mutual cooperation between the second graphite inner layer and the amorphous carbon outer layer in the composite coating layer to make the negative electrode material have the high capacity, the low irreversible capacity, and the excellent power performance.
NEGATIVE ELECTRODE MATERIAL AND PREPARATION METHOD THEREFOR, AND LITHIUM-ION BATTERY
The present application provides a negative electrode material, a preparation method thereof, and a lithium ion battery. The negative electrode material comprises a first graphite core and a composite coating layer coated on the first graphite core. The composite coating layer comprises a second graphite inner layer formed on the surface of the first graphite core and an amorphous carbon outer layer formed on the surface of the second graphite inner layer. The second graphite inner layer is graphite microcrystal. The preparation method comprises: mixing the first graphite and the second graphite and performing the coating treatment to obtain the first graphite coated with the second graphite, wherein the second graphite is graphite microcrystals; and making the first graphite coated with the second graphite, coated with carbon, to obtain the negative electrode material. The negative electrode material provided in the present application utilizes the mutual cooperation between the second graphite inner layer and the amorphous carbon outer layer in the composite coating layer to make the negative electrode material have the high capacity, the low irreversible capacity, and the excellent power performance.
SPHERICAL PARTICLES COMPRISING CARBON NANOMATERIAL-GRAFT-POLYOLEFIN AND METHODS OF PRODUCTION AND USES THEREOF
A nonlimiting example method of forming highly spherical carbon nanomaterial-graft-polyolefin (CNM-g-polyolefin) particles may comprising: mixing a mixture comprising: (a) a CNM-g-polyolefin comprising a polyolefin grafted to a carbon nanomaterial, (b) a carrier fluid that is immiscible with the polyolefin of the CNM-g-polyolefin, optionally (c) a thermoplastic polymer not grafted to a CNM, and optionally (d) an emulsion stabilizer at a temperature greater than a melting point or softening temperature of the polyolefin of the CNM-g-polyolefin and the thermoplastic polymer, when included, and at a shear rate sufficiently high to disperse the CNM-g-polyolefin in the carrier fluid; cooling the mixture to below the melting point or softening temperature to form the CNM-g-polyolefin particles; and separating the CNM-g-polyolefin particles from the carrier fluid.