A negative electrode active material includes a carbon material, where the carbon material has a specific degree of graphitization and aspect ratio distribution. A degree of graphitization Gr of the carbon material measured by an X-ray diffraction analysis method is 0.82 to 0.92, and based on a total quantity of particles of the carbon material, a proportion of particles with an aspect ratio greater than 3.3 in the carbon material is less than 10%. The negative electrode active material helps to improve cycle performance of the electrochemical apparatus. FIG. 1.

A negative electrode active material includes a carbon material, where the carbon material has a specific degree of graphitization and aspect ratio distribution. A degree of graphitization Gr of the carbon material measured by an X-ray diffraction analysis method is 0.82 to 0.92, and based on a total quantity of particles of the carbon material, a proportion of particles with an aspect ratio greater than 3.3 in the carbon material is less than 10%. The negative electrode active material helps to improve cycle performance of the electrochemical apparatus. FIG. 1.

There is provided a method of synthesizing a porous carbon-sulfur composite comprising the step of carbonizing a carbon material having a metal-organic framework (MOF) at a temperature of 800-1000° C. to produce a porous carbon, mixing and heating the porous carbon with sulfur to infuse the sulfur (melt diffusion) into the pores of the porous carbon and removing excess sulfur not infused into the pores or present on the surface of the porous carbon. There is also provided a cathode comprising the porous carbon-sulfur composite and a method of preparing the cathode by mixing with conductive carbon and a polymer binder. The cathode finds use in an electrochemical cell comprising a sodium or lithium anode.

There is provided a method of synthesizing a porous carbon-sulfur composite comprising the step of carbonizing a carbon material having a metal-organic framework (MOF) at a temperature of 800-1000° C. to produce a porous carbon, mixing and heating the porous carbon with sulfur to infuse the sulfur (melt diffusion) into the pores of the porous carbon and removing excess sulfur not infused into the pores or present on the surface of the porous carbon. There is also provided a cathode comprising the porous carbon-sulfur composite and a method of preparing the cathode by mixing with conductive carbon and a polymer binder. The cathode finds use in an electrochemical cell comprising a sodium or lithium anode.

The present disclosure relates to a positive electrode slurry for a lithium-sulfur battery including a positive electrode active material, an electrically conductive material, a binder and a solvent, where the ratio of the average particle diameter (D.sub.50) of the positive electrode active material and the positive electrode slurry is 1.5 or less, and the phase angle at 1 Hz of the positive electrode slurry is 50° or more. The positive electrode slurry for the lithium-sulfur battery of the present disclosure exhibits excellent flowability even while having a high solid content, thereby making it possible to manufacture a positive electrode for a lithium-sulfur battery with excellent electrochemical properties and improving the productivity and economic feasibility of the manufacturing process of the positive electrode for the lithium-sulfur battery.

The present disclosure relates to a positive electrode slurry for a lithium-sulfur battery including a positive electrode active material, an electrically conductive material, a binder and a solvent, where the ratio of the average particle diameter (D.sub.50) of the positive electrode active material and the positive electrode slurry is 1.5 or less, and the phase angle at 1 Hz of the positive electrode slurry is 50° or more. The positive electrode slurry for the lithium-sulfur battery of the present disclosure exhibits excellent flowability even while having a high solid content, thereby making it possible to manufacture a positive electrode for a lithium-sulfur battery with excellent electrochemical properties and improving the productivity and economic feasibility of the manufacturing process of the positive electrode for the lithium-sulfur battery.

A cathode structure for a battery includes a substrate having an electrically conductive surface and an electrode deposited onto the electrically conductive surface. The electrode is made of two or more electrode materials, including (i) one or more active materials, and (ii) specified weight percentage ranges of multi-walled carbon nanotubes (“MWCNTs”), or milled carbon fibers (“MCFs”), or a mixture of MWCNTs and MCFs. Using the specified weight percentage ranges, the electrode may be produced with a thickness of greater than 120 μm. Also disclosed are a slurry formulation for producing thick electrodes for a battery, and a method of fabricating a cathode structure for a battery.

A cathode structure for a battery includes a substrate having an electrically conductive surface and an electrode deposited onto the electrically conductive surface. The electrode is made of two or more electrode materials, including (i) one or more active materials, and (ii) specified weight percentage ranges of multi-walled carbon nanotubes (“MWCNTs”), or milled carbon fibers (“MCFs”), or a mixture of MWCNTs and MCFs. Using the specified weight percentage ranges, the electrode may be produced with a thickness of greater than 120 μm. Also disclosed are a slurry formulation for producing thick electrodes for a battery, and a method of fabricating a cathode structure for a battery.

Embodiments of the present disclosure generally relate to carbon materials for battery electrodes and methods for preparing such carbon materials. More specifically, embodiments relate to coated nano-ordered carbon particles and methods for coating a carbon film onto carbonaceous particles to produce the coated nano-ordered carbon particles which can be used as an anode material within a rechargeable battery, such as a sodium-ion battery, other types of batteries. In one or more embodiments, a method for producing coated nano-ordered carbon particles is provided and includes exposing a carbon-containing material to an expanding agent to produce expanded carbonaceous particles during an expanding process, heating the expanded carbonaceous particles during an annealing process, and depositing a carbon film on the nano-ordered carbon particles to produce coated nano-ordered carbon particles during a carbon coating process.

Embodiments of the present disclosure generally relate to carbon materials for battery electrodes and methods for preparing such carbon materials. More specifically, embodiments relate to coated nano-ordered carbon particles and methods for coating a carbon film onto carbonaceous particles to produce the coated nano-ordered carbon particles which can be used as an anode material within a rechargeable battery, such as a sodium-ion battery, other types of batteries. In one or more embodiments, a method for producing coated nano-ordered carbon particles is provided and includes exposing a carbon-containing material to an expanding agent to produce expanded carbonaceous particles during an expanding process, heating the expanded carbonaceous particles during an annealing process, and depositing a carbon film on the nano-ordered carbon particles to produce coated nano-ordered carbon particles during a carbon coating process.