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FAQ Modern Standby

for the record i only got 7 hours once xD most of the time is around 4-5

Same here (and there are a couple other similar posts in this same forum with the same issues too).

I disabled the turbo boost and half the cores on the bios which seems to have improved things somewhat along with a very conservative tlp configuration (that i even have to do so is ridiculous, but oh well). When I examine things in linux it seems like both the touchpad and the wireless are being quite naughty, specially the touchpad seems to be using WAY too much power and way too often, so you could try using an external one. wireless so far is a no go for me, albeit i have a few things to try with the killer drivers/config that may help. If they do work I'll let you know.
So far my best run with this config has been 7 hours, with no wifi, 10% brightness and running a few containers inconsistently, which is not a huge load. (and even that seems VERY inconsistent).

I am having the same issue. Here in Switzerland the developer edition with Ubuntu preloaded wasn't available, so I got the Windows version and installed Ubuntu 20.04, with Dell drivers. However, the laptop battery lasts less than 4 hours and empties overnight on suspend.

What is the official procedure to follow here? Is there a dedicated Dell Linux team that can help me fix this?

I just got my XPS 13 DE (i5 & FHD for the best battery life) and I'm having the same battery life issue of ~4 hours. Has this problem been fixed yet? If not I'll probably return it because the main reason I got this laptop was the best battery life. 

Same Problem Here after almost a year of ownership.

Bought the 9310 early this year, and it dies in suspend mode overnight. 
May sell for macbook air. This issue is so bad.