Automakers want to produce many more electric vehicles. This will require a lot more batteries, so car companies, including Tesla, are lining up all the materials they will need. Yesterday, two Chinese suppliers of battery materials disclosed agreements with Tesla, according to several reports citing regulatory filings abroad. Tesla, a leader in the electric vehicle business, did not immediately respond to a request for comment. Zhejiang Huayou Cobalt, a processor of cobalt and other metals, is one of the companies. Cobalt-based electric vehicle batteries generally have higher costs and better range than other alternatives, so automakers often use cobalt in…