Okay, maybe ‘expel’ isn’t the right word here, but hear me out.
When I park my Ioniq 5 in the garage to charge overnight with a level 2 charger, I come out in the morning and the garage smells musty, there’s condensation on the windows, and the concrete under the battery is wet.
Is this normal? My garage isn’t the best-insulated, and where I live, temperatures can drop to -30°F, so cracking open windows for ventilation isn’t really an option right now.
Yep, this is pretty normal. Many EVs use the air conditioner to cool the battery pack while charging, which causes condensation that can leave a small puddle under the car, just like cabin AC does. Unless there are other warning signs, I wouldn’t worry too much.
@martin
While it’s not an issue with the car itself, that musty smell and condensation are definitely problems for your garage! One suggestion is to place a bowl under the car to catch the water—some even suggest an insulated bowl to help reduce evaporation. Another idea could be installing a heat recovery ventilator, which would allow ventilation without letting in too much cold air.
@martin
Didn’t get to read my original thought, but here’s something different to consider.
Thomas said:
@martin
Didn’t get to read my original thought, but here’s something different to consider.
What if you replaced the air with liquid in a loop system?
Thomas said:
@martin
Didn’t get to read my original thought, but here’s something different to consider.
What if you replaced the air with liquid in a loop system?
The air is cooling the liquid or gas used in the system, causing water to condense out, similar to how air conditioning works.
In a snowy area with a warm garage and charging vehicle, this is pretty normal. You could look into a dehumidifier.
Robert said:
In a snowy area with a warm garage and charging vehicle, this is pretty normal. You could look into a dehumidifier.
Honestly, it sounds like OP’s car is acting like a dehumidifier.
@jessicah
Actually, it’s more like a humidifier. Might be a good idea to have something in place to collect the water as it condenses.
Christopher said:
@jessicah
Actually, it’s more like a humidifier. Might be a good idea to have something in place to collect the water as it condenses.
A humidifier increases humidity by adding water to the air. The car isn’t doing that, it’s actually causing condensation.
Christopher said:
@jessicah
Actually, it’s more like a humidifier. Might be a good idea to have something in place to collect the water as it condenses.
No, it’s more like a dehumidifier. The AC is cooling the battery, which condenses water that drips under the car. Putting a bowl under it to catch the water would help.
@Gabriel
If it’s truly a dehumidifier, why is OP’s garage still humid? Many people actually use dehumidifiers in garages for this reason.
Christopher said:
@Gabriel
If it’s truly a dehumidifier, why is OP’s garage still humid? Many people actually use dehumidifiers in garages for this reason.
If a lot of water is condensing, it means there’s plenty of humidity in OP’s garage air. If the car is collecting this moisture, then it’s removing some humidity, so technically it’s dehumidifying.
@jessicah
This is the kind of debate that makes forums like this fun!
@jessicah
Every time you open the garage, humidity equalizes. The car pulls in humid air, cools it, and the moisture ends up on the floor. Rinse and repeat, and the garage isn’t any drier overall.
Christopher said:
@jessicah
Every time you open the garage, humidity equalizes. The car pulls in humid air, cools it, and the moisture ends up on the floor. Rinse and repeat, and the garage isn’t any drier overall.
We’re saying the car collects humidity from the air and condenses it. Put something under the car, catch the water, and you’ll have less humidity.
@Gabriel
You’re not really understanding my point, but okay. 
Christopher said:
@Gabriel
You’re not really understanding my point, but okay.
Dude, it’s simple. A humidifier adds water, while a dehumidifier collects it. Since OP isn’t adding water manually, it’s dehumidifying.
@Randy
This seems like it got missed by the admins.
@Gabriel
It’s dehumidifying, but because it’s releasing the water back into the garage, it’s not making a big difference.