After 2,5 hours and 421 pictures the supplied EN-EL15b battery showed 41% remaining charge.
Due to the fact that it was early morning with an overcast sky, both viewfinder and back display only needed moderate brightness, which for sure influences battery consumption. With bright sunlight I would expect a total runtime between 3 and 4 hours and approximately 500 to 600 pictures. Shooting several bursts, more than 1.000 pictures per battery charge seem possible.
I quickly gave up on the auto area AF mode, which supposedly replaces the §d tracking of modern DSLRs. This function needs more time to evaluate properly, The best results for fast moving animals were achieved by using Wide-S focus point in AF-C mode. The best animals for testing are the sea lions in our zoo. They move fast and change direction pretty often.
Here are a series of 100 % crops, taken with the Z7, FTZ and 70-200mm 2,8 VR II. The exif data is also included as screenshot excerpt. The focus only missed in picture 4 slightly:
In my opinion the Z7 fares better than the D800 in focus tracking, but does not reach D4 level. D500 and D850 in a completely different league due to the new AF module.
When it comes to AF-S mode, the Z7 is comparable to the D850 in regard to focus speed and precision.