A battery pack case + Quad-lock is what I used to use. I got a Garmin for the battery life. But I didn't find that useful for navigation - slow and really hard

A battery pack case + Quad-lock is what I used to use. I got a Garmin for the battery life. But I didn't find that useful for navigation - slow and really hard to set destination and doesn't always pick the safest bike path (Google isn't great either but in my area it consistently chooses inner bike path over path that run through multi-lane roads).