PoPeyE_z

Hi Folks,
New to this forum!
Preparing to receive my 2024 GLC300 4MATIC in the dead of winter in the frigid northern mid-west, and there will be times it'll just sit in my garage for days, if not, longer.
Anybody know who the manufacturer is and type of battery MB is using as this car's mild hybrid battery?
Anyone know if a 48V battery could be charged on this car? If so, what charger/maintainer would you recommend?
I plan to use a battery tender on the 12V battery. Will this take care of the 48V battery by charging the 12V battery?
Appreciate your feedback!

MJ50

moved to X254 forum...

RA040624

Hello I am looking for this chain of information. I too am wondering if the 48 volt can be charged. The thread says it was moved to the x254 forum well that's what I'm looking at right now and I don't see it. Can you shed some light where this information has gone. Thank you

superswiss

As far as I understand it, MHEV systems have DC-to-DC converters to go from 12V to 48V and vice versa to charge both batteries with the ISG. So, you don't have to worry about the 48V battery. If you put the 12V on a tender it will if necessary charge the 48V battery. Also, the 48V battery is a lithium battery as opposed to most 12V batteries being AGM batteries. Lithium batteries are much happier if kept partially charged between 20-80%, so the 48V battery rarely needs to actually be charged up if the car is parked for a longer period. It'll last longer the more it's kept at a partial charge. Fully charging a lithium battery regularly will shorten its lifecycle.

RA040624

That's good information. Thank you for that. I did not know there was a DC to DC converter. That makes sense that all you would need to do is put a trickle charge on your 12-volt for periods of non-use. Thanks

Gitzer

If memory serves, not too long ago I saw a post where the poster took apart the 48v “battery”. It is actually a plastic box with two large capacitors in it, not really a battery as one would usually think, although you could say a capacitor is a form of battery (holds a charge).

RA040624

Yes I'm familiar with nickel hydrid batteries or lithium. Some of the very smallest of them can be used to jumpstart cars and carry it in your back pocket. They are very powerful and if touched incorrectly will fry you. That lithium battery is located in the front of the car underneath the cabin air filter, it is a med sized battery with a lot of connections to it that feed the engine and other parts.
I would say this is something that you would not really need to touch or be concerned about. All of the charging is done through the 12-volt battery in the rear of the car. I found that if you ever should get stranded by your rolling electronic computer that you are driving, you can always disconnect the ground connection at the rear 12 volt battery and reconnect. This will reboot the system without losing any of your settings. But you should not have to ever do this if your system has been properly software updated. That is a big thing with these new 23 2024 model Mercedes GLC300 x254 engine. If you ever encounter quirky warning messages or oddities, then it most likely is software related. All of these modules have to be correct in their software versions and synced up so they communicate properly. Mercedes dictates what the dealer should do to troubleshoot these problems. So being patient is par for the course as the dealerships are told what and what not to do when there are software issues. The jury is still out on all of this in my eyes, if you are located in the outback and drive back roads and are subjected to elements of nature, snow and rain. I don't feel comfortable in driving one of these around. But that's just me keep it simple! Hope this banter is informative.