Tesla completes world's largest lithium-ion battery in less than 100 days

No one expected it to be true. But Tesla's founder Elon Musk kept good on his promise of building the world's largest lithium-ion battery in 100 days. His self-imposed deadline was December 1, 2017.

After being asked in 2016 by fellow billionaire Mike Cannon-Brookes if he would take funding and build a solution to power South Australia's mid-north region, Musk replied that not only he'd do it but he would also do it fast or, otherwise, he would not charge a dime for the $50-million project.

Cannon-Brookes approached Musk on Twitter following a major blackout that left around 30,000 homes without power across the state. That's roughly the number of customers that Tesla's giant battery will service.

"South Australia is set to have backup power in place this summer through the world's largest lithium-ion battery, which is set to be energised for the first time in the coming days as it enters a phase of regulatory testing," state premier Jay Weatherill wrote in a press release. His office is now in charge of taking care of the tab.

"While others are just talking, we are delivering our energy plan,” Weatherill added. “The world's largest lithium-ion battery will be an important part of our energy mix, and it sends the clearest message that South Australia will be leading renewable energy with battery storage.”

Dubbed "Powerpack," the humongous artifact is connected to a wind farm operated by French energy firm Neoen. The battery is expected to hold enough power for thousands of homes during periods of excess demand that could result in blackouts.

Last year's events were caused by severe winds that tore transmission towers from the ground.