Billionaire Elon Musk's giant battery being built in South Australia will be energised in coming days and begin testing, indicating Tesla is on track to meet a 100-day self-imposed deadline to install the system.

Tesla power packs have now been fully installed on a site near a wind farm north of Adelaide and will be tested to ensure the battery meets standards laid down by the energy market operator, the South Australia state government said in a statement on Thursday.

South Australia's Premier Jay Weatherill said in the statement he will join representatives from Tesla and others next week to officially launch the battery, which "has put South Australia and Jamestown on the map as a world leader in renewable energy with battery storage."

"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 a leader renewable energy with battery storage", he said.