“Lithium-ion battery pack prices, which were above $1,100 per kilowatt-hour in 2010, have fallen 89% in real terms to $137/kWh in 2020. By 2023, average prices will be close to $100/kWh, according to the latest forecast from research company BloombergNEF (BNEF).”
$100/kWh is the fabled price at which EVs become cheaper than fossils.