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This winter we are going to be away for 5 months. Was wondering if it would be fine to leave the CTEK hooked up under the hood on the posts for this period of time? The car will be in a garage during the winter.
Also was wondering if it would be safe since we are dealing with a lithium Ion battery? The charger sits at 13.5-6 on float.
I had my 2021 GLE 450 for two winters and it sat on my CTek 5 for the entirety of both. The 48v died in early December 2021, but I’m sure the sitting on the tender had nothing to do with the failure…
My 2021 GLE 450 has sat through two summers (approximately 4 1.2 months) on the CTEK 5.0 so far and is in the third right now. No issues. Car is in air conditioned garage.
I use one made by Victron Energy, A company that is very well regarded in the marine industry. They have a similar charger, but it is available with up to 15a of output for faster charging.
Are we thinking a 5 month stay on my CTEK 5.0 shouldn’t damage the Lithium Ion Battery? On float it’s automatically holding the charge at 13.5v.
Hopefully not overloading the lithium battery. The AGM 12V battery should be okay.
The car will be in a garage for the winter where it could get to -30 degs in winter.
Dealer really doesn’t know. Although they have cars sitting outside in these temperatures on lots at these cold temperatures.
You shouldn't try to charge a Lithium battery at low temperatures (below freezing). My guess (hope) is that the battery management system would prevent charging at -30°. You do need to keep the AGM battery charged. A discharged AGM battery will freeze at a much higher temperature than a fully charged battery. A fully charged AGM battery should be ok down -30°. I don't know if the lithium battery will draw down the AGM battery if the car is not on a charger. If so, you run a real risk of freezing the AGM battery.
The car will be in a garage for the winter where it could get to -30 degs in winter.
-30? Do you mean Minus 30 or Below 30? I think if you're storing the car inside a building where it gets to minus 30, you are going to have all sorts of problems.
I live in Canada and the winters here do get cold. The temps can get to -30. In terms of Fahrenheit or Centigrade at -40 degs is the same. Left our Honda Pilot on a battery tender all last winter and other Mercedes cars and had no problem. My question to him was about the lithium battery.
Anyway I talked to the foreman/ head mechanic at my Mercedes dealership. He said there are lots of customers who leave their cars in garages with a smart battery charger attached all winter with no problems with those temperatures. He said the CTEK is a recommended charger.
He said the charger has to be a “ smart” charger which will only charge when needed and keep the batteries
on float. It’s not pushing in a full charge all the time.
Yes, many cities in Canada in winter can be -15 F in winter for 6 weeks or more. Many cars have plug in engine heaters plus wrap around battery heaters that plug in also. Believe it or not, the heat is worse on the batteries than really cold weather. In my boat, you charge up, unhook the negative cables from the batteries and leave it. They don’t freeze but go into a hibernation. Come spring they are still at 12.6V charge.My question about leaving my 450 in the garage was mainly concern about the Lithium Ion battery.
As mentioned, a smart charger is the answer and will work fine.
08-09-2023, 05:01 PM
