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Should I be worried about this?

7 to 15 day HV battery standby?

2322 Views 14 Replies 8 Participants Last post by  sokoloff
I am relocating to VA from UT for work. My ED will be transported and i was told it will take anywhere from 7 to 15 days to arrive in VA. Does anyone know how long the HV battery holds charge for if standing by or if it loses charge at all just sitting for a week or two? Kinda worried that the car will arrive after the 15 days with a dead HV battery and cause it to go bad/brick.
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Can't believe they were all hooked up to charging stations on the boat from Germany, so you should be OK. Just make sure the 12v battery has a full charge before the car goes on the transporter. :)
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As jwright mentions, make sure you've got a good 12v battery. I've left one of my cars sit for a week or more with no issues and it didn't always have a full charge, maybe 50% plus.

Len
2014 EV Coupe 19,500 miles
2014 EV Cabriolet 16,500 miles
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I had an "incident" with my smart and it has been laid up while I have been waiting on parts and my body has been repairing. Went to check it after 10 days. Dead 12 volt. I think I left the dome on when I was pulling the SD card from my cameras. I was freaking out. Long story short, had to jump it from my ICE and after two weeks I still had 100% charge in the traction battery. You should be fine, and I agree with everyone else make sure your 12 volt is topped off.
On a day to day basis, how does the 12v battery get charged? I just left on a business trip that was suppose to last a month, but now I realize I may need to cut it short to get back to charge the 12v battery. I’ve never had to charge the 12v battery, it’s always seemed to be okay. I charged the Drive battery to 100% and disconnected the charger before I left. My vehicle is a 2017 Prime.
I've heard both ways. It only charges when the key is on, and it charges from the traction battery as needed. Could be a difference in the firmware. But from my experience with my 2016, the 12 volt drained and the traction was still 100%, which leads me to think it is only when the key is on. I topped off my traction battery when I parked it Dec 14th. My 12 volt went to zero. 10 days later I jumped the car from my ICE. Just checked today still 100% in the traction. I'm sure the cars sat on lots for way more than 30 days without maintenance. I wouldn't cut my trip short.
I've heard both ways. It only charges when the key is on, and it charges from the traction battery as needed. Could be a difference in the firmware. But from my experience with my 2016, the 12 volt drained and the traction was still 100%, which leads me to think it is only when the key is on. I topped off my traction battery when I parked it Dec 14th. My 12 volt went to zero. 10 days later I jumped the car from my ICE. Just checked today still 100% in the traction. I'm sure the cars sat on lots for way more than 30 days without maintenance. I wouldn't cut my trip short.
Does your ED have the 2016 BMS software update? More on this in this thread:

When I left it was charged at 100% and I unplugged it. Should I ask a relative to go and plug it back in? Will that protect the Drive battery?
My only concern would be the ambient temperature along the trip. If you're doing it in the winter, if it's going to be below freezing for some of the trip the car MAY expend some energy trying to keep the pack at a reasonable temperature.

I think the official temperature it kicks in the heaters at is -5°F. This is why they encourage dealers and customers in colder climates to keep the cars plugged in (or to do routine checks). I've had a few instances where I've seen an 8% drain over the day when parked at work outside when it's been bitter cold out (around -13°F, which happens a week or two a year here at times).

If it's above freezing most or all of the trip, you'll likely only see a few percentage points lost per week at best. The 12V becomes the next larger concern, as others have noted. But even that should be fine for a week or two on it's own if it's topped off before the trip starts.
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When I left it was charged at 100% and I unplugged it. Should I ask a relative to go and plug it back in? Will that protect the Drive battery?
Lithium ion batteries do not self-discharge - so the car should stay at 100 percent. Since you car is a 453 and is not prone to that BMS software bug that causes the 451 ED battery to totally discharge itself when the 12 volt battery goes flat, you should be fine.

Also on the 451's, keeping the car plugged in for charging when the HV battery is full does not charge the 12V battery. If fact, the charging plug does even get energized unless the car sends a "HV battery needs charging" signal.

To be sure the 12V battery stays charged, the keyswitch needs to be turned on for a few minutes every 2 weeks or so.
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Lithium ion batteries do not self-discharge - so the car should stay at 100 percent. Since you car is a 453 and is not prone to that BMS software bug that causes the 451 ED battery to totally discharge itself when the 12 volt battery goes flat, you should be fine.

Also on the 451's, keeping the car plugged in for charging when the HV battery is full does not charge the 12V battery. If fact, the charging plug does even get energized unless the car sends a "HV battery needs charging" signal.

To be sure the 12V battery stays charged, the keyswitch needs to be turned on for a few minutes every 2 weeks or so.
Thank you. I bought this 2017 Electric Smart only a few months ago, and I love it. It drives like a sports car and can do a u-turn in my driveway. I'd hate for something to go wrong.
I bought this 2017 Electric Smart only a few months ago, and I love it. It drives like a sports car and can do a u-turn in my driveway
Same here bought a 2017 in July. It's still under warranty, so if the battery fails... anyways, I believe the 12v battery issue is more with the 451 ED's, but the 453 ED's and EQ's like ours not so much.
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Here is a follow up to my original question/post. I got back after 4 weeks, and opened the door and noticed that the drive battery was at approximately 98% and the 12v battery (I'm not sure, but the orange bar was still orange).

I couldn't drive it for a week because of bad weather, but as soon as I could everything worked fine. So it sat for 5 weeks with no harm to 12v battery or Drive battery. I drove it for several days till the charge got down to 38% and then plugged it in for a full charge.
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That is excellent news! Thank you for posting this information!(y)(y)
Okay Buckaroo - good news for you and likely for all 453 electric owners. The issue with a discharged battery seems to be a problem for the 451 drivers and maybe just the ones that haven't had the 2016 computer update?

Len
2014 EV Coupe 19,500 miles
2014 EV Cabriolet 17,000 miles
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