We are Ohio - South Carolina snowbirds and typically leave a car plugged in at each house. The has never been a problem when both cars were Teslas. We set the charge level to 60% and used the Tesla mobile charging cables to keep them charged for 6 months at a time. Right now we are using a Webasto charging cable to charge the EQE SUV and I'm not comfortable using that unsupervised for 6 months. I have ordered a Tesla Universal Wall Mount and will install it in our Ohio house. So if that calms my charging cable reliability concern the question then becomes how will the EQE SUV do if it is plugged in for 6 months?
Does anyone have any experience with long term storage?

 

Should be happy as a clam!

 

@bytemaster0 Have you stored an EQE for months? I'm surprised that I received only your reply. Maybe the vehicle is too new for others to have done the long term storage thing. My fingers will be crossed.

 

I actually haven't - I did just check the owner's manual, and this is what it suggests:

My long-term experience with Li-Ion batteries in a research setting bears out their recommendation - don't leave it connected. However, at some point you'll also get self-discharge of the lead-acid battery, which may consume some power from the HV battery at times to bring it back up. The only reason I can see why one *wouldn't* want to connect it to an EVSE long-term is that it starts creating short charge cycles, which can be detrimental to your battery, whether a Tesla, MB, or anything else. Practically though, I think you'll probably be okay. The battery self-discharge on these cars is extremely low, especially given that the contactors open up to disconnect the HV battery. Up to you. Personally, I'd probably leave it disconnected and then have a neighbor plug it in overnight once every month or two. Practically, I don't think I'd want to be away from the EQE that long.

 

Thank you for the advice. I like the "have a neighbor plug it in every couple of months" suggestion. I'll go that route. I just don't trust the Mercedes battery management system.

 

I totally trust the BMS. Question is if anything arises between EVSE and supply equipment. I strongly believe it'll work fine, but why put wear on the battery if you don't have to? Sounds like a plan.