Trickle charge parked outdoors in low (20deg.) temp

[BeckyB]

New owner, looking for battery advice. Going to my moms overnight, she's at 8000 feet, no garage, will get cold overnight (between 10-20 deg)..... is it beneficial to plug in to her 110 outlet to trickle charge a little to lower the negative impacts of the cold?

Sponsored

 

[Shawnybs]

Short answer.. Yes ha.

 

[SilverII]

Yes - 100% plug it in

 

[Funhiker2022]

I did 110 v charging once in the cold and it used all the power trying to heat the battery, so I didn’t end up getting much (or any) charge added to the battery. I gave up after not seeing any benefit and just drove to a fast charger. So don’t rely on it adding any range in the cold.

 

[Plummer43]

If super cold you will have a negative effect with more energy used from the battery to attempt to warm the battery to receive a charge.

 

[tjrivian]

If super cold you will have a negative effect with more energy used from the battery to attempt to warm the battery to receive a charge.

Agree. I don't yet have my Rivian, but that's been my exact experience in a Tesla. Plugged in to 120V/15A outlet in the cold and I lost more range than when it was not plugged in.

A 120V/15A outlet only provides 1.8kW. From other threads, when the Rivian is trying to charge even in normal temperatures it draws 600W baseline to run the computers and stuff like that. So that leaves only 1200W for charging. But in the cold it needs to turn on the heater to heat up the battery to a temperature where it can accept a charge, and needs to keep running the heater to keep the battery at that temperature(the charging losses at ~1200W charging don't produce enough heat themselves to keep the battery warm). In really cold temperatures the heater itself will draw more than 1200W, so the only place it has to get that extra energy from is pulling it from the battery!

So short answer - in normal temperatures it's fine to plug in to 120V/15A outlets and get the few miles per hour of charging that you'll get. But in cold temperatures you'll actually end up losing energy on a 120V/15A outlet. If you can find a 240V/15A or higher then that should be enough power to overcome the battery heating losses.

 

[sherold]

Try keeping it plugged in at all times that you are not using it. If you plug it in with warm batteries fresh off of a drive, you might stand a chance of keeping the battery temps stable enough just naturally from charging, as well as adding a small amount of charge. Not saying that will work but, its worth a shot. Once the batteries are cold soaked you are pretty much screwed at adding any charge to them through a 120V-15A circuit. This is where it would be nice for you to run off a 20A circuit.

 

[Drott]

The last two years I have spent a week in northern Montana during Christmas/New Years with the truck parked outside and plugged in a 120v. I would usually gain about a mile per hour. After a week without driving, starting from around 20%, I was full or nearly and ready for the drive home. Definitely plug in.

 

[Grandizer52]

Can you get a splitter and use two 120V plugs on separate breakers, or is there an easy accessible 120V outside?

 

[COdogman]

I never miss a chance to plug in. In that kind of cold just don't expect it to add any range, however.

Also, welcome fellow Lovelander!

 

[Laserboy1054]

Another, very small, advantage to being plugged in is you won't use any precious battery energy to heat the cabin to something tolerable before you depart. This would probably be something like 1 kWh, so it's not a huge deal. But I always figure that pulling energy from the wall is preferable to pulling it from the battery any time the option is available.

 

[Charged]

My R1T has been through two winters in NH, always parked outside, and I only use 110V to charge. I typically add 2 miles/hr, even in the very cold depths of winter. The key is to plug in when the battery is still warm from driving; otherwise it can take 3 hours or so before the battery warms sufficiently to add miles. Even if the 110V charging adds only 1-2 miles/hr, if you precondition the vehicle while still plugged in, the efficiency when you start driving will be much better than starting cold soaked.

 

[HaveBlue]

I don't bother plugging in unless I need charge.

 

[Rural1T]

My R1T has been through two winters in NH, always parked outside, and I only use 110V to charge. I typically add 2 miles/hr, even in the very cold depths of winter. The key is to plug in when the battery is still warm from driving; otherwise it can take 3 hours or so before the battery warms sufficiently to add miles. Even if the 110V charging adds only 1-2 miles/hr, if you precondition the vehicle while still plugged in, the efficiency when you start driving will be much better than starting cold soaked.

+1. The key is to plug in when the battery is still warm. The battery has a lot of thermal mass, so it takes a lot of energy to heat the battery, but not much energy to maintain temperature once it's warm.

On my G1 Dual Max, plugged into a 110 wall outlet I normally charge at about 1%/hr in warm temps. Parked outside at temps around 10°F, I charge at about 0.5%/hr. More than worth it overnight especially considering the benefits of a warm cabin and battery in the morning.

 

[BeckyB]

wow - this has been very helpful, thank you everyone!!

Sponsored