11-01-2019 04:07 AM - edited 11-01-2019 04:08 AM
yes, without any problem.
I use as well an hero7 battery.
the only odd thing is the "handle" that on hero7 battery is towards the door, a little gymnastic when you pull out.
when first insert, a message was displayed "use hero8 battery for full experience blablabla something". but I do not think it makes a difference, as both have the same capacity.
11-01-2019 12:20 PM
Yes, it should be compatible.
Please check this link as well if you want to know more details about battery compatibility.