I don't know what kind of batteries Sikorsky are using, but I can tell you that something is wrong here, either with the figures or the batteries used.
48.1kWh and 1100 pounds. Let's dissect this; That's 48.100Wh and 500kg. That translates to 96Wh/kg.
I can buy off the shelf Li-Ion batteries that deliver about 400Wh/kg, so what kind of stuff have Sikorsky been using? Lead acid?
400Wh/kg would give the same helicopter an hours endurance. That's a huge difference.