The battery of the Withings Pulse can last up to 2 weeks on a single charge.

To maximize the battery life: 

• Synchronize your data while the Withings Pulse is charging
• Limit the use of the heart rate measurement feature
• Check your activity data directly on the Withings Pulse less frequently

You can check the state of the battery in the Withings App by touching My Devices and searching for your Pulse in the list of your devices.