Results of Mach-E being unplugged and not driven for 3 weeks

I broke my driving foot and was in a cast for weeks so I decided to do a mock "airport parking" experiment.

My MME was last driven on March 24th but wasn't unplugged till the 27th. I set it to charge to 90%. I didn't plug it in or start it again until April 20th. I did open the doors a few times, so its not a perfect trial.

It went into "deep sleep mode" at some point. I would guesstimate after 2 weeks. I didn't check the app regularly so I am not sure.

I did not plug it in before I pressed "Start". I wanted to recreate airport parking as best as I could.

It started right up. The gauge read 89%. I plugged it in and it took about 20 minutes to get back to 90% on the 110v. ( Level 2 charger goes in next week ).
So, not terribly scientific, but I hope it gives you some vague idea of how much power it will lose over about 3 weeks.

I posted this over on reddit too.

We have been on a two week trip leaving the Mach E in the stable. The car was left at 64% charge when we left and I just checked and it is still reading 64% per the app. Not good to leave it at full charge for long periods of time.

Gaigan71 said:

I broke my driving foot and was in a cast for weeks so I decided to do a mock "airport parking" experiment.

My MME was last driven on March 24th but wasn't unplugged till the 27th. I set it to charge to 90%. I didn't plug it in or start it again until April 20th. I did open the doors a few times, so its not a perfect trial.

It went into "deep sleep mode" at some point. I would guesstimate after 2 weeks. I didn't check the app regularly so I am not sure.

I did not plug it in before I pressed "Start". I wanted to recreate airport parking as best as I could.

It started right up. The gauge read 89%. I plugged it in and it took about 20 minutes to get back to 90% on the 110v. ( Level 2 charger goes in next week ).
So, not terribly scientific, but I hope it gives you some vague idea of how much power it will lose over about 3 weeks.

I posted this over on reddit too.

Click to expand...

Was it in a garage? What temp did it experience during that time?

It was garaged. Not much temp change. I am in the Bay area.

Gaigan71 said:

I broke my driving foot and was in a cast for weeks so I decided to do a mock "airport parking" experiment.

My MME was last driven on March 24th but wasn't unplugged till the 27th. I set it to charge to 90%. I didn't plug it in or start it again until April 20th. I did open the doors a few times, so its not a perfect trial.

It went into "deep sleep mode" at some point. I would guesstimate after 2 weeks. I didn't check the app regularly so I am not sure.

I did not plug it in before I pressed "Start". I wanted to recreate airport parking as best as I could.

It started right up. The gauge read 89%. I plugged it in and it took about 20 minutes to get back to 90% on the 110v. ( Level 2 charger goes in next week ).
So, not terribly scientific, but I hope it gives you some vague idea of how much power it will lose over about 3 weeks.

I posted this over on reddit too.

Click to expand...

Thx for posting results. Now we need same test in sub zero temps. I can do this next January

If you’re planning on leaving the car undriven for an extended period of time, you should knock it down to around 60% for storage. I get that you didn’t go into this planning on not using the car for 3 weeks, and I’m not upset, I’m just saying that we have a pretty good idea of how to manage LiPo batteries.

jeffdawgfan said:

We have been on a two week trip leaving the Mach E in the stable. The car was left at 64% charge when we left and I just checked and it is still reading 64% per the app. Not good to leave it at full charge for long periods of time.

Click to expand...

I likewise left mine for 10 days while away. I had 51% SOC and 130 miles of range left. When I came back it was the same. My car was parked outside in the lot and I live in NYC. I thought it was good, but I am new to EVs.

I mean, yeah with a Tesla, sure, but at the same time I think it’s a lot less critical with the MME since it has a larger buffer. Not the end of the world to keep it at 90%.

JoeDimwit said:

If you’re planning on leaving the car undriven for an extended period of time, you should knock it down to around 60% for storage. I get that you didn’t go into this planning on not using the car for 3 weeks, and I’m not upset, I’m just saying that we have a pretty good idea of how to manage LiPo batteries.

Click to expand...

Orangefirefish said:

I mean, yeah with a Tesla, sure, but at the same time I think it’s a lot less critical with the MME since it has a larger buffer. Not the end of the world to keep it at 90%.

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I do not have, nor have I ever had, a Tesla. I am using my drones and their batteries as a basis for my comment. And, I still maintain that a LiPo battery should be stored at about 60% for long term storage to minimize battery health impact.

JoeDimwit said:

I do not have, nor have I ever had, a Tesla. I am using my drones and their batteries as a basis for my comment. And, I still maintain that a LiPo battery should be stored at about 60% for long term storage to minimize battery health impact.

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That is good information to know, thank you. Fingers crossed the next time it will be for something fun like a vacation and by the time I drive to the airport it won't be anywhere 90%.

Orangefirefish said:

I mean, yeah with a Tesla, sure, but at the same time I think it’s a lot less critical with the MME since it has a larger buffer. Not the end of the world to keep it at 90%.

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I think the manual states not to store the car at "full charge".

krafty81 said:

I think the manual states not to store the car at "full charge".

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Yes, the Ford manual recommends if you're going to store the vehicle for 30 days or more to leave it at 50%.

Storage State of Charge
You can increase the battery life by maintaining your state of charge below 100%. When you park your vehicle for an extended period of 30 days or more, we recommend your battery be at an approximately 50% state of charge. Storing your vehicle's high voltage battery at higher states of charge is less favorable than storing at lower states of charge.

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https://www.fordservicecontent.com/...&userMarket=USA&div=f&vFilteringEnabled=False

I've experienced the same, and in fact in a couple of instances I've even seen 1% higher after parking the car for a few days. I'm not saying the car actually gained phantom energy, that would be silly. But something about how the state of charge is being measured under load, obviously changed after the car sat for a while because it reported 1% higher after a few days.

For the most part though, I haven't noticed any drain at all after letting it sit for a week in my underground condo parking lot, and the state of charge is exactly where it was when I parked it.

JoeDimwit said:

I do not have, nor have I ever had, a Tesla. I am using my drones and their batteries as a basis for my comment. And, I still maintain that a LiPo battery should be stored at about 60% for long term storage to minimize battery health impact.

Click to expand...

Is there a typical period of days at which non-use is considered long term storage? I'm assuming it's probably measured in weeks, right?

Only ask because I'm going to be parking at the airport for 6 days on May 1st, and they have free L2 charging. Figured I'd just not charge all week and max out my free charge at the parking garage ?. So I'd have 5 days sitting at 100% SOC.