First decide what you need the reserve for
You may need your phone for communication, a ticket or a map, while the exoskeleton battery is there for your planned walk. Being able to transfer energy between devices does not make it free. Before reaching for a cable, consider which reserve matters more right now and how you will finish your route.
This article concerns the Supply Power To External Device function in the Hypershell X Series v5.1 manual, not every device with a USB-C port. A different series needs its own instructions; a similar name does not confirm identical behaviour.
The connector makes no promise about speed
The manual specifies a maximum of 5 W (5 V / 1 A) for this function. The cable must be compatible, and the external device’s requirements must match that output. While supplying power to an external device, exoskeleton assistance and changes to the mode or power level are unavailable.
So a USB-C label on a phone or cable does not answer every question. Check your particular phone’s requirements, and do not count on gaining a specific charge percentage in ten minutes: this article does not provide that calculation for your pair of devices.
The stop needs a deliberate finish
The exoskeleton automatically powers off when the cable is disconnected; it must be switched on again to resume operation. Energy used by the external device reduces the available range. The full procedure for using this function is on page 38 of the manual.
Editorial advice: treat this power supply as a separate stop, not something to do unnoticed while moving. Before continuing, check the device’s state according to its instructions. Do not assume that removing the cable automatically restores everything to its previous state.
What to plan before leaving home
Check phone and cable compatibility, find the relevant manual section, and decide whether to take a separate power source for communication. This is not a requirement to buy an accessory: sometimes charging the phone before leaving and avoiding a plan built entirely around the backup option is enough.
Do not convert the charge percentage transferred to a phone into supposedly exact kilometres remaining. The practical takeaway is simpler: plan communication and your return separately from advertised battery capacity. The X Pro and X Carbon cards below let you compare specific devices; this function is not a promise of compatibility with every phone.