How can I backup MacBook before the battery runs out? I would like to backup my MacBook (early 2016 model with 256 GB storage), but while backing up the storage, the battery would run out before completing the backup.

The MacBook has only one port (USB Type-C). I backup it to my USB 3.0 HDD via Type-C converter by Apple. But since it only has one port, I could not back it up while recharging the batter on the laptop.

I already deleted and/or moved some files to a cloud storage, but still it has about 200GB to back up, and the backup couldn't finish before the battery runs out.

Is there any workaround on this problem?
This adapter will help you. Also useful for other use cases.

The USB-C Digital AV Multiport Adapter lets you connect your USB-C or Thunderbolt 3 (USB-C) enabled Mac to an HDMI display, while also connecting a standard USB device and a USB-C charging cable.



Or this one:
HyperDrive USB Type-C Hub with 4K HDMI Support

Matching colours. Turns a single USB Type-C port into 4 ports (HDMI, 2 x USB 3.0, USB Type-C with Power Delivery)