Or the fact that China is the primary source of lithium and if Chinese car brands start exporting their cars worldwide, there is no reason for them give the raw resources to western car manufacturers, forcing them to buy the whole battery pack from China.
Australia will sell the raw resource ( hard-rock spodumene ) to anyone that wants a X-year contract - it's on them to process the concentrate (although we are currently building out spodumene processing).
Australia has one of the biggest lithium reserves, and is the biggest producer of lithium by weight, with most of its production coming from mines in Western Australia.
Lithium mining in Chile is the second largest in the world in terms of extraction after it was surpassed by Australia in 2012. Chile, like Argentina and Bolivia, is located within the Lithium Triangle, an area of South America that houses the largest known reserves of lithium on the planet.