Leaving an EV parked long term

[andrew_j]

A friend in Montreal left for 6 weeks to South America with his EV (BMW i4 at 60% charge). Came back to parking garage where left unplugged. Returned, remote started and found it at 58% and “started up” no issue in 13F weather.

His 328 ix wagon ICE had a dead battery

 

[demarpaint]

My son went on 7 deployments a lot longer than that and his ICE vehicles with a solar trickle charger fired up on the first try. W/O the trickle charger a jump and a ride and the battery was fine.

 

[Pelican]

A friend in Montreal left for 6 weeks to South America with his EV (BMW i4 at 60% charge). Came back to parking garage where left unplugged. Returned, remote started and found it at 58% and “started up” no issue in 13F weather.

His 328 ix wagon ICE had a dead battery

There is parasitic draw on both vehicles, but the EV's battery is at least x10 the size of the ICE, so what's your point?

 

[Astro14]

Part of the reason that I have considered EV is that I often leave a car parked for weeks at a time, most often (but not always) at an airport. I last drove my V70R on December 17th for example. Fortunately, it’s in my buddy’s garage in Highlands Ranch, CO, and he takes it out once in a while.

At about the 3-4 week point, my Mercedes S-class can get irritated with me, the big H8 AGM will run down - and while it might start - it will have all sorts of electrical problems. My wife’s SL is very similar - after three weeks, the “convenience” battery, a big AGM H8 in the trunk, will be flat, and the car will start on the starting battery (a small LA under the hood), but there will be electric problems.

As a result of several experiences with flat batteries and the subsequent electric problems, both cars get driven at least weekly, or stored on a maintainer, and I am careful to plan their parking so as not to exceed three weeks.

A car that I can leave for several weeks is very attractive. But EVs, like Teslas, have lots of active functions and modes that can drain the battery much more quickly while it is sitting, so, one has to be careful about what features are left active or “on” while it is parked for a very long time.

 

[Cujet]

The battery itself will not rapidly self deplete, once the state of charge is less than 100%, depending on temperature.

There are many claims that say 1.5% to 3% per month. But the self discharge "curve" is not the same for all types of batteries, depends on state of charge, age and temperature.

Of course, the car's settings matter too. As many cars will maintain active video surveillance.

 

[andrew_j]

My son went on 7 deployments a lot longer than that and his ICE vehicles with a solar trickle charger fired up on the first try. W/O the trickle charger a jump and a ride and the battery was fine.

Modern vehicle or something old school/limited electronics for keyless entry or worst proximity key? Makes an incredible difference with modern stuff where ICE has become worst.

Not sure how useful solar charger is in Montreal when it snows/builds or in a parking garage.

Jump is not what I ever want at airport arrival .

 

[demarpaint]

Modern vehicle or something old school/limited electronics for keyless entry or worst proximity key? Makes an incredible difference with modern stuff where ICE has become worst.

Not sure how useful solar charger is in Montreal when it snows/builds or in a parking garage.

Jump is not what I ever want at airport arrival .

Six weeks with a good battery should not a problem. Since I retired my van sometimes sits longer than that under a carport, with no trickle charger, it fires right up, and it has an old school clock with a sweep second hand drawing on the battery, nonstop. Lets face it, love or hate an EV or ICE, getting an ICE vehicle started with a dead battery is a lot easier than an EV in extreme heat or cold.

 

[y_p_w]

Modern vehicle or something old school/limited electronics for keyless entry or worst proximity key? Makes an incredible difference with modern stuff where ICE has become worst.

Not sure how useful solar charger is in Montreal when it snows/builds or in a parking garage.

Jump is not what I ever want at airport arrival .

Most airport parking will offer a jump since it’s pretty common. Ideally an EV would be plugged in and perhaps left at a 50% max. The airport parking that provides a 120V outlet kind of worries me since the mobile charging equipment I’ve used can be removed at any time. But there are some airports that have free Level 1 charging equipment which would be good to just maintain. Maybe even charge higher just before leaving by changing the max remotely. But I would like stuff like cameras on in a parking lot just in case.

 

[loneryder]

Part of the reason that I have considered EV is that I often leave a car parked for weeks at a time, most often (but not always) at an airport. I last drove my V70R on December 17th for example. Fortunately, it’s in my buddy’s garage in Highlands Ranch, CO, and he takes it out once in a while.

At about the 3-4 week point, my Mercedes S-class can get irritated with me, the big H8 AGM will run down - and while it might start - it will have all sorts of electrical problems. My wife’s SL is very similar - after three weeks, the “convenience” battery, a big AGM H8 in the trunk, will be flat, and the car will start on the starting battery (a small LA under the hood), but there will be electric problems.

As a result of several experiences with flat batteries and the subsequent electric problems, both cars get driven at least weekly, or stored on a maintainer, and I am careful to plan their parking so as not to exceed three weeks.

A car that I can leave for several weeks is very attractive. But EVs, like Teslas, have lots of active functions and modes that can drain the battery much more quickly while it is sitting, so, one has to be careful about what features are left active or “on” while it is parked for a very long time.

Maintainers are a must with a sitting MB.

 

[Astro14]

Maintainers are a must with a sitting MB.

Yeah. A real surprise how much they disliked sitting. And three weeks seemed to be the critical number with those cars, despite the very large AGM.

Drive them often and they’re very happy. Fire right up. They will start with a partially discharged battery, but they exhibit all kinds of electric faults until that battery is back up to proper voltage.

I‘ve left the V70 sitting for much longer, and it fired right up, but it’s a much simpler car with a big battery, located in the rear of the car, out of the heat/cold.

The ability to leave the car parked for several weeks without worry is part of the appeal of an EV.

 

[ecotourist]

Maintainers are a must with a sitting MB.

BMWs don't like sitting either.

 

[JeffKeryk]

About a year ago our '21 RX450h with a 1A NOCO killed the original AGM sitting for a month(?) or so. I had the maintainer attached to the front; the 12v battery is in the rear.
I got a Costco Interstate AGM and a Battery Tender Plus (more amps) hooked directly to the battery (thanks @The Critic for your advice).

What's a poor boy to do? If the Tesla sits I turn off the climate control; if it sits for weeks I leave it plugged in.

 

[Danh]

Current Honda hybrids use the HV battery to start the ICE. The conventional 12V battery exists only to initiate the communication process. Honda cautions that a hybrid cannot be left undriven more than 90 days or the engine won’t start. I believe the only solution is a tow to a Honda dealer to restore the HV battery.

Unlikely to be an issue for most, but if you’re a snowbird or in the military…

 

[Jetronic]

The battery itself will not rapidly self deplete, once the state of charge is less than 100%, depending on temperature.

There are many claims that say 1.5% to 3% per month. But the self discharge "curve" is not the same for all types of batteries, depends on state of charge, age and temperature.

Of course, the car's settings matter too. As many cars will maintain active video surveillance.

I "parked" my electric bike on november 1 with about 80% battery capacity, and earlier this week I checked the charge and it was still where I left it. In fact it indicated 100% until I turned on the lights to create a bit of load. The charge indicator has 5 sections.

I'm sure discharge doesn't exceed 1.5% pier month by much, if even that. But there will be very little draw from the bike

 

[PandaBear]

Part of the reason that I have considered EV is that I often leave a car parked for weeks at a time, most often (but not always) at an airport. I last drove my V70R on December 17th for example. Fortunately, it’s in my buddy’s garage in Highlands Ranch, CO, and he takes it out once in a while.

At about the 3-4 week point, my Mercedes S-class can get irritated with me, the big H8 AGM will run down - and while it might start - it will have all sorts of electrical problems. My wife’s SL is very similar - after three weeks, the “convenience” battery, a big AGM H8 in the trunk, will be flat, and the car will start on the starting battery (a small LA under the hood), but there will be electric problems.

As a result of several experiences with flat batteries and the subsequent electric problems, both cars get driven at least weekly, or stored on a maintainer, and I am careful to plan their parking so as not to exceed three weeks.

A car that I can leave for several weeks is very attractive. But EVs, like Teslas, have lots of active functions and modes that can drain the battery much more quickly while it is sitting, so, one has to be careful about what features are left active or “on” while it is parked for a very long time.

I have left my Prius in my house for 1 month (9 year old car, original lead acid battery still) and it "start" right up. When I bought it from the dealer new, it was a left over new car from the year before sitting on the lot for 6 months. Didn't have any problem since I bought it.

I think if a NiMh battery in a hybrid can do then an EV would be fine. The problem with EV is if you leave it for say, 1 year and the main battery get permanently discharged then it is expensive to replace unlike a lead acid.

 

[y_p_w]

I have left my Prius in my house for 1 month (9 year old car, original lead acid battery still) and it "start" right up. When I bought it from the dealer new, it was a left over new car from the year before sitting on the lot for 6 months. Didn't have any problem since I bought it.

I think if a NiMh battery in a hybrid can do then an EV would be fine. The problem with EV is if you leave it for say, 1 year and the main battery get permanently discharged then it is expensive to replace unlike a lead acid.

Yeah - but it shouldn't be left in a garage alone for years like the 356 replica from 48 Hours. If an EV can be connected indefinitely, the battery will be maintained very nicely as long as the charging equipment doesn't fail. I would suggest something like that stored long term be attached to a Level 1 charging setup with a 50% charge limit and scheduled charging at midnight since that can be done pretty easily. Ideally it would be where charging could be scheduled once a week, but I don't think that weekly scheduled charging is an option yet with any EV.

And with remote monitoring it could work pretty well. If charging equipment fails, it might be possible to ask a friend to go over and maybe replace the equipment.

The problem isn't necessarily with lithium-ion batteries. I've bought electronics where the battery came from the factory at 50% charge and it might have been around that even after a year in storage. But EVs are always on to some degree and will slowly discharge the battery as well as some self-discharge. But that's mostly from all the parasitic draws. However, it's not going to be like an ICE where it might be wonky at first after not being driven, where oil has to be distributed as well as other fluids. Granted most EVs have some sort of liquid cooling systems for the batteries.

 

[Torrid]

Most modern cars don't like to sit long. There's a lot of parasitic drain with modern systems and the batteries can only hold so much charge with enough reserve to start an engine. I would not let any modern car sit for more than a couple of weeks without some form of battery maintainer.

 

[y_p_w]

Most modern cars don't like to sit long. There's a lot of parasitic drain with modern systems and the batteries can only hold so much charge with enough reserve to start an engine. I would not let any modern car sit for more than a couple of weeks without some form of battery maintainer.

Most of an EV can actually handle that for a while, except the batteries. Motors and electronics can be stored for years without issues. Not sure about the cooling system, but I don't believe it's quite like all the stuff in an ICE.

ICE can have issues beyond just the battery when the various fluids aren't redistributed periodically. Motor oil washes down, although I understand the wear additives tend to still be there.

So obviously maintaining the battery in an EV should be adequate.

 

[Torrid]

Most of an EV can actually handle that for a while, except the batteries. Motors and electronics can be stored for years without issues. Not sure about the cooling system, but I don't believe it's quite like all the stuff in an ICE.

ICE can have issues beyond just the battery when the various fluids aren't redistributed periodically. Motor oil washes down, although I understand the wear additives tend to still be there.

So obviously maintaining the battery in an EV should be adequate.

For the most part. I do wonder if the gearboxes in EVs would be prone to leaking too long term. When I posted I wasn't thinking of really long term storage. Maybe a month. With either type of vehicle I'd just keep the battery topped up. I feel like that would be overall easier leaving an EV plugged in with a battery limit set and allowing that to keep charge in the car, assuming it will still randomly charge the 12V. If I was concerned about the low voltage being charged I'd just wake the car up randomly to allow it to charge. On an ICE vehicle I'd be more apprehensive about running the car without getting it to temperature and just use a battery tender.

 

[y_p_w]

For the most part. I do wonder if the gearboxes in EVs would be prone to leaking too long term. When I posted I wasn't thinking of really long term storage. Maybe a month. With either type of vehicle I'd just keep the battery topped up. I feel like that would be overall easier leaving an EV plugged in with a battery limit set and allowing that to keep charge in the car, assuming it will still randomly charge the 12V. If I was concerned about the low voltage being charged I'd just wake the car up randomly to allow it to charge. On an ICE vehicle I'd be more apprehensive about running the car without getting it to temperature and just use a battery tender.

Most people would do that in a garage. Obviously an ICE shouldn't be operated in a closed garage, although I understand CO poisoning isn't as common as it used to be. And the battery limit should probably be in the middle, which is easy enough to do with a Tesla, but I'm not sure about other manufacturers. I just wish that were possible with other devices, where I've heard of people going on extended trips hoping that they could leave their devices at home - perhaps up to a year. Those the typical recommendation is to get it down to 50% and turn it off, but there's no reason why they couldn't be left on indefinitely with an automatic maintain like how most have some sort of automatic maintain that's not truly at 100%, but top off cycles after a drop down to maybe 95%.

I mentioned a daily cycle is easy to program, but maybe something else like a 50%-45% cycle. However, with EVs there might be a desire to take advantage of lower time of use rates. Perhaps an extended storage setting that waits until hitting the bottom limit and then is ready to start charging at a set time of day.