Mike Nudelman/Business Insider
The anonymous official working for the South Korean company declined to provide its name because the company recently signed a non-disclosure agreement with Apple. But, according to the Etnews report, we do know that the South Korean battery company is comprised of roughly 20 employees and holds international patents for hollow batteries.
The lithium-ion batteries are cylindrical and have a hollow center with a thickness of "two fingers," according to the report. As MacRumors points out, it's possible the batteries are made by Korean Company Orange Power, which has a patent application for a hollow-type rechargeable battery.
Orange Power has 33 employees total, 25 of which specialize in research and development. But it's still to early to tell if Orange Power is, in fact, a partner of Apple's.
Apple did not immediately respond to Business Insider's request for comment.
Because batteries create most of their heat in the center, having a hollow center that supports air flow and cooling could minimize the need for a separate cooling device, Etnews points out. The parallel connection is advantageous because it expands the battery capacity.
According to the Orange Power patent application, the hollow battery design allows the batteries to be stacked in parallel or in series without any welding process.
European Patent Office
Apple isn't the only company looking to re-think battery design to advance its electric cars. Start-up Faraday Future is arranging its batteries in rows, or as the company calls it, "strings" so it's easy to change the battery capacity by adding or removing the strings.
Tesla is also investing heavily in battery technology through the construction of its giant battery factory the Gigafactory.
Apple recently tapped Bob Mansfield to lead Apple's car project after former head Steve Zadesky left the project in January. Apple has also been known to hire former Tesla engineers to work on the car.