According to a report from The New York Times, an unnamed Volkswagen executive said the automaker pays less than $100 per kWh for its batteries.
Electric vehicles are making progress, but internal combustion engines still make up a vast majority of cars on the road today.
The new framework will be an extension of last year's partnership on commercial vehicles, the companies told Reuters.
Tesla is doing everything it can to stop bleeding, but right now Wall Street couldn't care less.
"Chevy's presence in EVs will not be going away," Steve Majoros, Chevy's marketing chief, said in an interview with Business Insider.
"As challenges go, this is a good one to have," Musk said in the leaked email.
A widely followed Wall Street analyst says failures in service and parts could plague Tesla with even more problems.
A study by Crescent Electric Supply Company found that commuters in New York can save $55 by driving an electric car instead of a gas powered model.
Cadillac is in the midst of a product shift, selling more crossovers and moving away from traditional luxury as it becomes GM's main electric brand.