NEXEON LIMITED

This invention relates to particulate electroactive materials consisting of a plurality of composite particles, wherein the composite particles comprise a plurality of silicon nanoparticles dispersed within a conductive carbon matrix. The particulate material comprises 40 to 65 wt % silicon, at least 6 wt % and less than 20% oxygen, and has a weight ratio of the total amount of oxygen and nitrogen to silicon in the range of from 0.1 to 0.45 and a weight ratio of carbon to silicon in the range of from 0.1 to 1. The particulate electroactive materials are useful as an active component of an anode in a metal ion battery.

The invention relates to a process for preparing silicon-containing composite particles in a fluidized bed. Porous conductive particles having a defined particle size and pore structure are combined with a particulate additive having defined particle size, density and BET surface area. The combined porous conductive particles and particulate additive are subjected to chemical vapour infiltration in a fluidised bed to cause deposition of silicon in the pores of the porous conductive particles.

The invention relates to a particulate material and processes for the preparation thereof. The particulate material consists of a plurality of composite particles. The composite particles comprise a porous particle framework comprising micropores and/or mesopores. The total pore volume of micropores and mesopores as measured by gas adsorption is in the range from 0.4 to 2.2 cm 3 /g. The composite particles comprise a plurality of electroactive material domains and a plurality of modifier material domains disposed within the internal pore volume of the porous particle framework. At least a portion of the modifier material domains are located between adjacent electroactive material domains.

The invention relates to a particulate material comprising a plurality of composite particles, wherein the composite particles comprise: (a) a porous carbon framework comprising micropores and mesopores having a total pore volume of at least 0.6 cm 3 /g and no more than 2 cm 3 /g, where the volume fraction of micropores is in the range from 0.5 to 0.9 and the volume fraction of pores having a pore diameter no more than 10 nm is at least 0.75, and the porous carbon framework has a D 50 particle size of less than 20 μm; (b) silicon located within the micropores and/or mesopores of the porous carbon framework in a defined amount relative to the volume of the micropores and/or mesopores.

This invention relates to particulate electroactive materials comprising a plurality of composite particles, wherein the composite particles comprise: (a) a porous carbon framework including micropores and optional mesopores having a total volume of at least 0.7 cm 3 /g and up to 2 cm 3 /g, wherein at least half of the total micropore and mesopore volume is in the form of pores having a diameter of no more than 1.5 nm; and (b) silicon located within the micropores and optional mesopores of the porous carbon framework in a defined amount relative to the total volume of the micropores and optional mesopores.

This invention relates to particulate electroactive materials comprising a plurality of composite particles, wherein the composite particles comprise: (a) a porous carbon framework including micropores and optional mesopores having a combined total volume of at least 0.7 cm 3 /g, wherein at least half of the micropore/mesopore volume is in the form of pores having a diameter of no more than 1.5 nm; and (b) an electroactive material located within the micropores and/or mesopores of the porous carbon framework. The D 90 particle diameter of the composite particles is no more than 10 nm.

This invention relates to particulate electroactive materials consisting of a plurality of composite particles, wherein the composite particles comprise: (a) a porous carbon framework including micropores and/or mesopores having a total volume of at least 0.6 cm 3 /g, wherein at least half of the micropore/mesopore volume is in the form of pores having a diameter of no more than 2 nm; and (b) an electroactive material located within the micropores and/or mesopores of the porous carbon framework. The D 90 particle diameter of the composite particles is no more than 10 nm.

The disclosure relates to a process for preparing particulate materials having high electrochemical capacities that are suitable for use as anode active materials in rechargeable metal-ion batteries. In one aspect, the disclosure provides a process for preparing a particulate material comprising a plurality of composite particles. The process includes providing particulate porous carbon frameworks comprising micropores and/or mesopores, wherein the porous carbon frameworks have a D 50 particle diameter of at least 20 μm; depositing an electroactive material selected from silicon and alloys thereof into the micropores and/or mesopores of the porous carbon frameworks using a chemical vapour infiltration process in a fluidised bed reactor, to provide intermediate particles; and comminuting the intermediate particles to provide said composite particles.

The invention relates to a process for preparing composite particles, the process comprising the steps of: (a) providing a plurality of porous particles in a pressure reactor; (b) contacting the plurality of porous particles with a silicon precursor gas at conditions effective to cause deposition of silicon in the pores of the porous particles to provide composite particles comprising a porous particle framework and elemental silicon within the pores of the porous particle framework; and (c) during step (b), withdrawing an effluent gas from the pressure reactor, wherein the silicon precursor gas is introduced into the pressure reactor continuously.

The invention provides methods for providing composite particles with a carbon coating and the resulting core-shell particulate material. The process comprises subjecting a plurality of precursor composite particles to a heat treatment in contact with a pyrolytic carbon precursor such that an outer shell of a pyrolytic conductive carbon material is formed on the precursor composite particles, wherein the heat treatment is carried out at a temperature of no more than 700° C.