Yes. First, who's doing this? It sounds like Contemporary Amperex Technology Ltd in Ningde, Fujian Province, is providing the batteries. But there's no press release from them.[1] Also, their stock went down a bit today,

CATL is the world's largest lithium battery manufacturer. They produce about 40GWh of battery capacity a year, compared to Tesla's 35GWh or so. CATL has been roughly doubling production each year for the last few years. Their output is not exclusive to Tesla. They've mostly targeted China and European car manufacturers. They're building a huge battery plant, bigger than Tesla's "gigafactory", in Germany.[2]

If this is real, it's all about CATL.

[1] https://www.catlbattery.com/en/web/index.php/news/lists

[2] https://www.electrive.com/2019/02/04/catl-plans-up-100-gwh-b...