Elon Musk has finished building the biggest battery in the world

Elon Musk made a bet to build the world's biggest battery in 100 days or he'd pay for it.

And he's done.

Tesla has completed installing its colossal lithium ion battery in South Australia, a Powerpack system with 100 megawatts of capacity. But now comes the test.

Regulatory testing will begin in the next few days to ensure the battery is optimised and meets AEMO and South Australian Government requirements, before operation commences on Dec. 1.