Silicon-carbon composite material, preparation method of silicon-carbon composite material, and lithium ion battery containing silicon-carbon composite material

[0031] This embodiment provides a method for preparing a silicon-carbon composite material, comprising the following steps:

[0032] (1) Weigh fumed silica powder (particle size: 30nm) and calcium particles (particle size: 1mm), wherein the amount of calcium is 100% of the theoretical amount that can completely reduce the fumed silica powder. The two were mixed, toluene was added thereto, and steel balls were added, put into a planetary ball mill, and ball milled at 350 rpm for 6 hours to obtain a mixed slurry. Transfer the above mixed slurry into a crucible, then put the crucible into an atmosphere furnace, raise the temperature to 600°C at 5°C / min under the protection of argon, and keep it warm for 1 hour; then raise the temperature to 800°C at 5°C / min , and keep warm for 1 hour to obtain a composite of porous silicon-calcium oxide.

[0033] (2) Put the porous silicon-calcium oxide composite into a beaker, and add hydrochloric acid to it, wherein the amount of hydrochloric ...

[0042] This embodiment provides a method for preparing a silicon-carbon composite material, comprising the following steps:

[0043] (1) Weigh mesoporous silica powder (SBA-15, which is a kind of mesoporous molecular sieve), potassium (particle size 1mm), and the amount of potassium is such that the mesoporous silica powder can completely 80% of the theoretical amount of reduction. The two were mixed and cyclohexane was added thereto, and then steel balls were added, put into a planetary ball mill, and ball milled at 350 rpm for 8 hours to obtain a mixed slurry. Transfer the above mixed slurry into the crucible, then put the crucible into the atmosphere furnace, raise the temperature to 550°C under the protection of argon at 5°C / min, and keep it for 5 hours; then raise the temperature to 800°C at 5°C / min , and kept for 12 hours to obtain a composite of porous silicon-potassium oxide.

[0044] (2) Put the composite of porous silicon-potassium oxide into a beaker, and add acet...

[0048] This embodiment provides a method for preparing a silicon-carbon composite material, comprising the following steps:

[0049] (1) Weigh quartz sand and magnesium (particle size: 1mm), and the amount of magnesium is 110% of the theoretical amount that can completely reduce the quartz sand. The two were mixed and cyclohexane was added thereto, and then steel balls were added, put into a planetary ball mill, and ball milled at 300 rpm for 6 hours to obtain a mixed slurry. Transfer the above-mentioned mixed slurry into a crucible, then put the crucible into an atmosphere furnace, raise the temperature to 650°C at 5°C / min under the protection of argon, and keep it warm for 2 hours; then raise the temperature to 900°C at 5°C / min , kept for 3 hours to obtain a composite of porous silicon-magnesia.

[0050] (2) Put the porous silicon-magnesia composite into a beaker, and add a mixture of acetic acid and hydrochloric acid to it, wherein the amount of the mixture of acetic acid ...