how long long will the battery last recording video with an iphone 6 plus?

Thank you for replying.

I know all these things you mentioned, but virtually none of them will apply for the application I’m looking at.

All I am looking at is using the phone like a dash cam, as a camera to live video traffic approaching from behind and passing me as I’m riding my bike.

As I mentioned, I’m thinking of using my old iPhone 6 Plus like a dash cam to watch traffic passing me while I’m riding my ebike.

That means that I won’t be using the phone as normal.

The battery is in excellent shape, with 100% capacity available.

I will be deleting virtually all of the apps on it. So there will be no push notifications, and in fact I have almost never enabled that for most apps anyway.

Location services will be a non entity, except for possibly the phone alone.

Mail will not be on the phone, nor will any of the normal services of a phone.

I have never enabled Background App Refresh.

Connection to WiFi is a non entity on the road, cellular and wifi coverage won’t even be considered.

In fact it won’t even have any options for any of the things a phone is used for. It will be closer to an iPod than a phone.

All it will be is a camera. Therefore, my question is simply:

How long can the battery be expected to last while I’m videoing traffic approaching me from behind, and passing by me while I’m riding my bike?