So, importing the ChipMixer's private keys into a new Electrum wallet is fee-free, then I can send it to Binance, right?
That's correct.
I'd advise you make sure you download(ed) Electrum from electrum.org and verify the download:
https://bitcoinelectrum.com/how-to-verify-your-electrum-download/This is necessary to avoid malicious software steal your money.
I'd also advise you play around with Electrum (maybe on testnet, with free coins from Bitcoin Testnet Faucets - google it) to make sure you won't encounter surprises when you want to use it with real money.
You start Electrum on testnet with:
electrum.exe --testnet