pElon Musk announced a project to build the world’s largest lithium-ion battery in South Australia on July 7. And if the $33 million project isn’t delivered in under 100 days, the Tesla founder said it would be free.ppIn a bid to secure the state’s energy future, the South Australian government made a “historic agreement” with Tesla and renewable energy provider Neoen to install a 100-megawatt battery. The battery would store power generated from Neoen’s 99-turbine wind farm at Hornsdale, according to the Adelaide Advertisera.ppMusk said the battery would be three times more powerful than any other energy storage system on earth.ppThe video shows Musk and Neoene’s Deputy Chief Executive Romain Desrousseau with South Australia’s Premier Jay Wetherill at a press conference in the Adelaide Oval.ppThe ABC reporteda that the 100 day countdown will start once the grid interconnection agreement has been signed.