Are you are wondering what is silicon doing in batteries nowadays? Well, first you need to appreciate that this is not the same silicon some use to seal around windows. Silicon in its raw state is a blue-gray crystalline solid with a metallic luster. Although we hasten to add that is not a metal, but actually a metalloid.
What Are The Characteristics of (Silicon) Metalloids?
A metalloid is an element with properties between metals and non-metals. Accordingly, silicon:
- Conducts electricity, but not as effectively as a true metal can.
- Appears as shiny as a metal, but can be as brittle as a non-metal.
Thus silicon is a ‘hybrid’ element with mixed metallic and non-metallic properties. It is also a semiconductor, lying between an insulator and a true conductor.
We also find the silicon in batteries, in a variety of other electrical devices. Wikipedia includes transistors, solar cells, and integrated circuits among others.
This is good news for our environment, because silicon is the eighth commonest element in our universe. We find it out there in cosmic dusts, planetoids, and planets too.
More than 90% of our Earth’s crust comprises silicate minerals. In fact silicon, at 28% by mass, is the second most abundant element in our world.
More About Silicon In Batteries
We find silicon in modern lithium-ion battery anodes, where it improves energy storage density. Now, if we could use pure silicon instead of graphite, then those batteries could be ten-times more powerful.
But we can’t do that yet, because lithium-ions inserting between silicon anode layers may cause the metalloid to expand, and crack. The current solution adds small amounts of silicon to a graphite base, as the best compromise today.
And so, in a nut shell, what silicon does in lithium-ion batteries is boost energy storage density. It achieves this by accommodating more lithium-ions in the battery anode, to the extent practically possible.
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