Now I'm offering unsolicited advice, but have you changed your settings to save on the battery? You can google it. There are lots of settings which you probably don't need turned on. In particular, go to SETTINGS, then LOCATION SERVICES, then scroll all the way down to SYSTEM SERVICES. Many people turn a lot of those off.
Actually, I turned off all location services. I know where I am and I know where I'm going. I don't need Siri to tell me where the nearest coffee shop is located.
I also turned off all push notifications.
You might want to change your settings for your trip, even if you put them back to normal when you get home.
Or you might know all of this, and wish I would keep my mouth shut.