Yes, the Note 9 does have a supercapacitor inside (teardown)
Apart from the intriguing heat dissipation piping, which is not full of liquid nitrogen, but nevertheless does the job of taking away warmth from the chipset, allowing higher GPU clock speeds and the like, the new star of the show is... a supercapacitor. Just as we envisioned when the Note 9 was announced, the S Pen does feature its own power source inside to maintain the Bluetooth connectivity when you press its button for action.
It's just that the power draw comes from a K8373 Seiko Instruments supercapacitor, which gets charged via a coil near the tip of the stylus. The phone's own wireless charging coil, the new finger scanner, the dual camera with variable aperture, and the breathtakingly compact system board can all be seen in the pictures below, reiterating once again this marvel of Samsung's engineering.
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