2013 BMW X1, sitting during lockdown; battery drained after 2 weeks, normal or not?

[escapetomars]

So I let my 2013 BMW X1 sit for about 2 weeks during lock-down... frankly, there was just nowhere to go since everywhere was closed.
Things are opening up now where I live, and I went to start it today... battery was dead. Not totally dead (lights, locks, radio, etc still work), just too dead to turn over the engine and start the car (it almost makes it but not quite). I have another car which isn't dead to charge it from (and I will do that tomorrow), so it's not the end of the world. However, I was wondering if this was about a normal rate of battery drain, or a sign the battery probably needs to be replaced? I bought it used with the existing battery so I don't know how old the battery actually is.
For comparison, I also have a 2002 318ti, which was sitting more than a month and it started right up yesterday - but I imagine it has much less active electronics that can drain the battery over time...

[geargrinder]

Semi normal.

Yes the electronics drain when these cars sit.

Also could be battery condition however. When we bought ours from my father it had been driven intermittently and sat for long times - battery is not in great condition. Driving it / charging regularly solved that but we would not leave this car sitting for long without hooking up a 'tender' to it.

[jclausen]

The battery voltage does not have to drop to much before the engine will not start, recharge it properly

[balidawg]

My semi-rule-of-thumb is: one week or more of planned non drivage and she goes on the battery tender.
Car batteries seem to really dislike being discharged much, but they do self discharge (eeeeew!) and then there’s the BMW sleep drain.

[X135i]

Not normal. I live in Canada, Ontario. Winters get cold, lots of snow etc.
I usually store my x1 35i from : Dec-March. I take it out in April, it has ALWAYS started.
This year due to covid wife was working from home so no need for the x1, the battery 100% died when i tried to start it last week. I sold one of my other cars. So its been sitting since Dec.2019, i just changed the battery and it started right up.

Im the original owner of my 2013 x1 35i,
and its always been stored for 4 months , and started right up.
This year it was left for 12mths , and naturally battery was dead.

[jclausen]

Well I would consider your bmw the exception most bmws seem to not like to sit for any length of time, if they are I recommend the battery tender