Apparatus and process for semi-continuous and multi-step composite production
A method and apparatus produce silicon-carbon composite materials through a chemical vapor deposition or a thermal disposition process in a fluidized bed reactor on a semi-continuous basis. The produced silicon-carbon composite has a unique structure that silicon particles are uniformly dispersed, bonded and embedded into the carbon conductive matrix and forming a secondary structure. The produced silicon-carbon composite can be used as advanced anode materials for lithium battery and other electrochemical energy storage device.
1. A method for generating a silicon-carbon composite, comprising:
performing controlled silicon loading on a first carbon substrate in a reactor of a reactor-reservoir system, the controlled silicon loading on the first carbon substrate producing a silicon-carbon composite;
transferring the silicon-carbon composite from the reactor to a reservoir of the reactor-reservoir system, the transfer of the silicon-carbon composite occurring through a connection mechanism that connects the reactor and the reservoir;
closing the connection mechanism between the reactor and the reservoir after the transfer of the silicon-carbon to the reservoir; and
performing a controlled silicon loading on a second carbon substrate in the reactor of the reactor-reservoir system while the first silicon-carbon composite cools in the reservoir,
wherein the simultaneous silicon loading on the second carbon substrate and cooling of the first silicon-carbon composite produces silicon-carbon composite in a semi-continuous manner.
2. The method of claim 1 , wherein the reactor-reservoir system includes a fluidized bed reactor.
3. The method of claim 1 , further comprising producing a silicon-carbon composite and/or silicon-graphite composite from the carbon substrate.
4. The method of claim 3 , wherein the silicon-carbon and silicon-graphite composites are produced using chemical vapor deposition.
5. The method of claim 3 , wherein the silicon-carbon and silicon-graphite composites are produced using thermal deposition.
6. The method of claim 1 , wherein a gaseous material precursor decomposes via chemical vapor deposition or thermal deposition.
7. The method of claim 2 , further comprising:
receiving carbon powder into the reactor of the reactor-reservoir system;
providing an inert gas into the reactor of the reactor-reservoir system;
heating the reactor during an inert gas flow into the reactor of the reactor-reservoir system;
introducing reactive gas and a silicon precursor in the reactor of the reactor-reservoir system;
performing the controlled silicon loading on the first carbon substrate for a predetermined period of time; and
removing, after performing the controlled silicon loading on a first carbon substrate, the reactive gas and silicon precursor gas used for the controlled silicon loading on the first silicon substrate from the reactor of the reactor-reservoir system.
8. The method of claim 7 , further comprising:
cooling the silicon-carbon composite in the reservoir while the controlled silicon loading on the second carbon substrate is performed.
9. The method of claim 1 , wherein the silicon-carbon composite has a secondary, ball-like shape resulting from agglomerated silicon-graphite sheets.
10. The method of claim 9 , wherein the secondary, ball-like shape are formed inside the reservoir after transferring silicon-carbon composite from the first reactor into the reservoir while being cooled.
11. The method of claim 10 , wherein the secondary, ball-like shaped silicon-carbon composite particle are transferred into the reactor for silicon deposition to further increase the silicon loading.