To check on the battery status of your headset, plug it in to charge. While charging, go to the Halo Sport app and the charging screen will appear. The charge percentage will appear on the bottom of the screen.
When unplugged, if the headset's battery is low, the light will blink orange - indicating you need to charge your Halo Sport before you can start another Neuropriming session. If the battery is critically low, the light will blink red and Halo Sport will turn off.
A fully charged battery will provide you with 8 complete Neuropriming sessions, and a 20 minute charge will give you enough power to do one Neuropriming session.