I just came back from a 9.5 drive from Ontario to New Jersey to catch a 7 day Cruise. I left the car at the port unplugged with a charge of 56%. Temperatures at that time when I left the car was warming up but it was parked during a snow storm at start. When I came back it was still at 56%. This is probably not the answer you were looking for but just giving you an idea of my experience. I wouldn't think there will be an issue at all leaving it unplugged. Especially from reading not leaving it <20% or >80% charged for a long period of time.

 

I'm finally leaving the country after a few years of child rearing and a Global Pandemic.

Is it better to leave the car unplugged but charged or plugged in to keep the battery topped up if I'm leaving the car for a week?

It'll be late April, in a garage, so I can't imagine temps will get low, But I do know that the car does stuff when parked to keep the battery stable.

It is best to keep the battery no higher than 80% and no lower than 20% when not in use for some time, so as to not damage the battery. Keeping it around 50-60% is ideal. The only real worry you have is with the 12V battery under the hood, not the high voltage traction battery. The smaller 12v may go flat, depending upon state of charge and demand or drain from the vehicle. Assuming no drains, the larger traction battery should be looking after it and feeding it every so often. This takes very little charge from the larger traction battery. However, many have noted that this cars computer doesn't do enough to keep the 12v topped up and come back to a dead 12v battery.

So, if you have faith in your car, then leave it alone with everything off and doors locked. It should be fine under normal circumstances; a week is not that long.
If you have a low amperage trickle charger, you may hook it up to the 12V (be sure to turn off the aux battery charging setting from the dashboard settings) and close the hood tight.
Or, you could just detach the battery terminals from the 12v battery and reconnect when you return.
Good Luck.

 

I've previously left my 28 kWh IONIQ for up to 2 weeks in the garage while away with absolutely not problems. Leave it as close to 50% SoC as you can get, but anything between 20% and 80% is also fine. Lock it up, make sure the kay is not in close proximity and head on out. It will be fine while you're away.