On the battery? Where do you think NSG is going to "get" the battery?
So you're talking about a component rather than the whole boat?
The current Australian procurement contract philosophy is to 'solutionise' as little as possible, the contractor will know what's what and what will produce the best product. Now whether that's the best way to go about things is up for debate, but if the Government demands the supplier use a particular battery that they are unfamiliar with or whatever that's as likely to produce bad results as good.