It takes several hours to fully charge your Logitech Ultrathin Keyboard Cover. Low-power USB ports and low-power USB chargers may take longer to charge than other sources.
We recommend charging your keyboard until the charging light turns solid green.
To charge the keyboard:
Locate the USB Micro cable that came with your keyboard.
Insert the micro connector into the port on the keyboard.
Plug the larger USB plug into either a PC or your iPad charging adapter.
The charging light (with the lightning bolt beneath it) will:
Blink while the keyboard is charging
Turn solid green when your keyboard is fully charged
Please see answer 360023409593 for battery information.