Scott Morrison is comfortable with the advice his government has received on how Australia’s future submarine fleet will be powered after a former government adviser warned they could be obsolete before they hit the water.

The prime minister says when it comes to defence procurements there will always be many opinions.

“We will continue to rely, I think rightly, on the advice of our defence and security officials and advisers,” he told reporters after addressing an LNP state conference in Brisbane on Saturday.

Veteran military analyst and former government adviser Derek Woolner believes there should be an urgent rethink of how the French-designed Attack-class submarines on order are powered.

He says rather than the planned lead-acid batteries, the Attack-class submarines should be powered by lithium-ion technology.

While Mr Morrison said the latter technology has not yet been proved, Mr Woolner warns when the first submarine hits the water in the early 2030s “it’s going to be obsolete”.

“By that time, the Japanese will have their … lithium powered submarines in the water,” he told ABC television.

China too has heavily invested in battery technology, he says.

But Mr Morrison says these decisions have not been taken lightly.

“They have been done after extensive analysis and looking forward into the future, and we are comfortable with those decisions,” he said.

Under the $50 billion Attack-class program, an Australian subsidiary of French shipbuilding company Naval Group will construct 12 submarines.

-AAP