It takes approximately 1.5 to 2 hours to fully charge the battery. Once fully charged, the battery provides up to 120 minutes of wireless use, which is equivalent to about 4 pumping sessions.
The battery is charged via a USB cable and can also be charged using a power bank, allowing you to charge the breast pump even when you're on the go or away from home. The original charger is not strictly necessary as long as you have a suitable USB cable or power bank to charge the battery.