Elon Musk, the CEO of Tesla, has posted a letter from his “prospective professor” at Stanford University. The letter indicated a research project Musk may have worked on if he hadn’t dropped out of the elite university.

The letter, written by William D. Nix, professor of engineering at Stanford‘s Department of Material Science and Engineering, praised Musk for his “spot on” expertise in lithium batteries.

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“In a recent interview entitled: “Elon Musk on the Early Days of Tesla: Interview Part 1,” which was posted on YouTube, you mentioned meeting me at Stanford in 1995 as your prospective professor if you had enrolled in the graduate program at Stanford. This is just a brief note to say that your description of the issues of using Si for anodes for lithium batteries was spot on,” Nix wrote.

The professor further stated, “About 10 years ago we at Stanford did research on the very issues you described. Indeed, it almost seemed like you had read all of our papers. As a part of the work we did we found that since the crumbling of Si on lithiation is associated with the amorphization of crystalline Si, less crumbling can be achieved by starting with amorphous Si in the first place.”

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“Much larger Si particles can be lithiated without cracking if they are initially in the amorphous state. Using amorphous Si as particles in a carbon matrix might allow much higher volume fractions of Si to be loaded into carbon anodes. For all I know, someone may have already patented this idea,” he added.

“I thought you would like to hear about work you might have done,” Nix wrote before signing off.

Musk captioned a photograph of the letter, “Nice letter from Bill Nix, who would have been my prof at Stanford if I hadn’t put grad studies on (permanent) deferment.”

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Musk realised an hour later that he had given the PO Box information to millions of Twitter followers. Musk followed up with, “Might need a new PO Box after tweeting this.”