New batteries with close to diesel energy density permitting the replacement of the diesel generators and their fuel with a bigger battery. End result, an electric only submarine that can complete a full transit and patrol, submerged on a single charge. You want to extend the subs endurance, simple, rig our new generation support ships, which would likely be diesel electric themselves, to recharge the subs at sea.

Which battery types are you referring to?

 

Not my field but look more toward what is being achieved in automotive battery technology than the tried and true 1970's tech used in current gen DE subs. Once batteries reach a certain efficiency diesel fuel, diesel generators and all current tech AIP become nothing but dead weight that cuts into the potential battery space.

A low profile, stealthy, multihulled platform with minimal draft may actually be a better way to go than a semi submersible considering the shallow littoral waters in our region. Other factors would include shock resistance, acoustic silencing, top space for sensor location as well as the need to keep any helo deck as high as possible for safe operation of helo's and UAV's