In addition to a super capacitor I have been using a DC to DC battery device to backup my Raspberry Pi devices and they are working out very well after several months of use. These devices take DC power in and produce 5V DC out in the current design. The part I’m using is made by Adafruit and if future models of the Sense could incorporate an option to have a backup battery added this would be very useful. My UPS for DSL modem, router and switches has 300 ‘events’ over the past 2 years and the recent windy weather in NC locked up the Sense during one of those off - on - off - on power glitches and a much longer off period reset it. My other devices that have the Adafruit DC-DC battery continued to work and report data.