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Not quite the same as the manuals for the 451 and 453. Anything we ought to consider though?

Len
2014 EV Coupe 20,000 miles
2014 EV Cabriolet 17,500 miles
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The charge level if left idle could be questionable. I recently purchased a LiFePO4 battery for a trailer emergency brake. It said to leave the charge at 75% and to charge it every 6 months. For those who’s smart lives in the cold I like the 75% better, for it does some sort of self warming if the ambient gets too cold. Better protection from draining itself to death.

Just my humble opinion, I do not have an ED...
 

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MY08 cabrio MY09 cabrio Brabus MY15 ED
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Well that certainly muddies up the water?

BUT - it seems that the 453 ED is not as “vulnerable” as the early 451 ED? With such a small sample of 453 ED/EQ in N.A. it is almost impossible to draw any sound conclusions as to exactly what these “warnings” may really mean??

The more things change the more they remain the same as Daimler & friends once again kick their ugly stepchild to the curb???
 

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The thing about sitting at 100% charge is real. I saw some video by early e-Bike vendors whose batteries were failing way too soon. They figured out it was due to sitting on the shelf at 100% charge. On some cars you can set the percent to charge to. For us, it seems to be timing the charging with at least a short trip to bring things back down under 100%.
 

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But our cars don't ever get charged to 100%, almost, but not quite. Here is a line from our battery test unit:

SOC : 100.0 %, realSOC: 97.5 %

Is that enough of a cushion?

Len
2014 EV Coupe 20,000 miles
2014 EV Cabriolet 17,500 miles
 

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Tesla defaults to 80% for a daily charge. Some people do 90%. I don't think anyone knows for sure what's best.
 

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All this is the established wisdom regarding lithium batteries, except the "store at between 30 and 50 percent" seems a bit low to me. In the past about 60 percent was regarded as about right for storing lithium batteries.

Definitely don't store at 100 percent. And we also know that keeping it plugged in will not protect a 451 from "The Fatal BMS Bug". But then what about the warning in the 451 manual to keep it plugged if temperatures below -25C (-13F), presumably so battery heating can occur? This would break the "don't keep at 100 percent" rule. What does the 2020 453 manual say about cold weather conditions?

Then again, if future winters are like this past winter, it is a moot point for all but the morthernmost parts of the world. I don't think even Helsinki or Moscow saw -25C this past winter.
 

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Tesla defaults to 80% for a daily charge. Some people do 90%. I don't think anyone knows for sure what's best.
So the peak SOC can be set? Also, what does Tesla recommend about leaving the car parked in very cold temperatures?
 

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Yinzer, how about keeping the EVSE plugged in AND having a 12 V maintainer also plugged in? Do we have any data on that yet?
 

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Yinzer, how about keeping the EVSE plugged in AND having a 12 V maintainer also plugged in? Do we have any data on that yet?
That should be fine. But you really don't want to keep the battery at 100% for an extended period.
 

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That should be fine. But you really don't want to keep the battery at 100% for an extended period.
Thanks for the input. I completely agree about not wanting to store the car at 100% charge level.

That seems to be the Catch-22 of the ED. There's no simple way to make sure you are properly storing the car for extended periods of time.

Sent from my moto g(7) power using Tapatalk
 

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The battery pack does not self-discharge to any extent, so I would focus on jsut keeping the 12V battery charged. If -25C temperatures are anticipated, then the car need to be stored in a place that will stay warmer. Or, you could put a low wattage strip heater (like are used to keep pipes thawed) on the underside of the battery pack with a blanket of insulation underneath it.
 
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