We know that when Weir's expedition left earth for Atlantis they took a bunch of computers, radios, etc. with them that while powered by batteries still needed to recharged eventually. So How could they possibly managed to do that? Given that Atlantis was built by a highly evolved race that existed for several millions of years prior to old Ben Franklin discovered electricity while flying a kite. There had to have been some kind of interface the expedition used to recharge their less advanced tech, but they never showed it actually being done.