I was watching a guy on YT fumbling around with his GoPro batteries during a tournament and I was wondering, with the high capacity memory cards available today, why are folks still using the stock batteries for their cameras. I know when I'm out fishing, I don't want to have to worry about cameras going dead. There are solutions for supplying external power for your GoPros available today. (I use the older battery eliminator for my Hero 3 cameras, pictured.) Sometime in the near future I plan to upgrade to the Hero 7 cameras and the company highlighted in the video link below appears to have a solution for those cameras.
https://www.youtube.com/watch?v=S6Y7a3ZtoeE