Battery Tender for E-torque

[Swicago]

I have a 2020 with the 48V e-torque. Any idea of a battery tender for that 48V system? Does it need one and if so, would it also keep the 12V system charged(since it is interlinked with a dc to dc converter)? Or is it enough to just keep the 12V battery on a tender?
At the moment I do not put much engines hours on it and I know from my past car that after about 3weeks the battery is getting low. Any suggestions are appreciated.
Right now I just keep it on a 12V tender, but I don't want the 48V to be discharged to the point of no return(common with lithium)

 

[turkeybird56]

WOW, hmmmm, heck of a question. MY GUESS would be keep the 12V charged and let the system charge the 48V when operated. I have not even heard of ne 48V units out there, and to rely on a dc-dc up/down, hmmmm, that another question. Not sure which way the conversion would be best to route if U did. One would think the generator I believe down graded to 12V, but would that even work if vehicle not on??? Or is it the other way>? U definitely gonna have to talk to a wrench head with a lot of electrical experience on this one.

ADDED: Read up: 48V down to 12V, but I am not sure the unit work if vehicle not on. ALSO, the only 48V charging unit I saw was for a Golf Cart. Not sure I would want to Micky Mouse something to mess with that Battery pack, so my thought would be to Keep the 12V charged on a trickle/maintainer if U were concerned so U have the 12V to turn over the truck. Just my .$02 cents on this one.
NOTE: I AM NOT A MECHANIC, ALL ABOVE IMHO..............

 

[Swicago]

@turkeybird56 , thanks for the response. Not sure if the e-torque have a 12V starter. I thought 48V e-torque system starts the car. If there is still a 12V starter, then the 12V tender should be enough.
EDIT: just read it still has a conventional 12V starter for cold start ups. Still would be nice to know if there is a risk of the 48V battery draining from sitting around for 3 weeks or more

 

[turkeybird56]

BOIRD dunno. He not have dat new fangled system, got old fashioned standard 5.7. BUT my unedumacated guess would be: Keep the 12V charged. Once system starts, it will charge up the 48V pack, since the generator is a 48V system with step down to 12V.

ADDED: IF U were that concerned on the 48V, and U were good enuf, maybe there be a way to like rig up a golf cart 48V, BUT me thinks U PLAYING with fire there. Keep the 12V on a tender and just fire that bad boy up. All IMHO..........................

 

[cj7]

E-torque has a 12v battery, but a 48v starter/assist motor.
No need or easy way to connect a battery maintainer to the E-torque battery. Plus, you’d need one with a lithium chemistry-specific charging profile.

 

[turkeybird56]

E-torque has a 12v battery, but a 48v starter/assist motor.
No need or easy way to connect a battery maintainer to the E-torque battery. Plus, you’d need one with a lithium chemistry-specific charging profile.

WHY if I had and E-torque system, no way I would touch dat 48V battery pack, just keep 12V charged/and on trickle if needed.

 

[Jus Cruisin]

During the Michigan covid shut down, I used one of my Battery Tenders on my Ram. Never gave the eTorque a thought. With all the electronics, I figured it would kill the 12v battery within 5 or 6 weeks. I've got one hooked up to my GT 500 right now.

 

[les13]

If all accessories are run off 12v then the 12v system is what you'll want to maintain. The 48v being Lithium would need a balanced charger that would expensive and dangerous if done incorrectly. I would guess the 48v system has a built in low voltage cut off like most lithium systems. Prevents overdischarge damage. My 2 cents.

 

[Swicago]

I have been using a standard 12V tender...all appears to work perfectly. I only need the truck once every 4 to 6 weeks, but as said all works great

 

[ALT_F13]

I was barely using my RAM recently; it is more an offroad and road trip rig for me. I was always worried about using battery tender with eTorque. Battery never died, so no problems with cold start once a month, but still.
This thread gave me confidence to use battery tender with my RAM. I'll post an update if it gets on fire or explodes, otherwise consider that experiment went fine

 

[mikeru82]

By now I'm sure more people are at least aware of the basics of how the etorque system works. The generator/motor charges the 48v battery. A dc to dc converter that's part of the 48v battery pack charges the 12v battery in the engine bay. The 12v starter starts the engine when using the fob or the push button. The etorque generator/motor restarts the engine during stop/start operations. You can start the engine even if the 48v battery is flat, although you will see warnings about it. So as long as you keep the 12v battery charged you're golden.

 

[jimothy]

Reviving an old thread. Has anyone else monitored their 48V battery using JScan or AlfaOBD?

I was surprised by two things JScan showed me: the state of charge was consistently below 60%, and the voltage was around 44 V.

Are these values normal? 60% SoC strikes me as low, but not worrisomely so.

But 44V would be extremely low for a nominal 48V battery (perhaps it’s a 12S NMC battery, which would be 44.4V = 12 x 3.7).

I’m not have any issues with my eTorque; start/stop works, no codes or warnings. Just wondering if this is normal.

If you’ve got JScan or AlfaOBD and wouldn’t mind checking this out, I’d appreciate it. In JScan, it’s under the Battery Pack Control Module. Probably the same for Alfa, but I’ve never used it.

 

[Ellisstrong]

Reviving an old thread. Has anyone else monitored their 48V battery using JScan or AlfaOBD?

I was surprised by two things JScan showed me: the state of charge was consistently below 60%, and the voltage was around 44 V.

Are these values normal? 60% SoC strikes me as low, but not worrisomely so.

But 44V would be extremely low for a nominal 48V battery (perhaps it’s a 12S NMC battery, which would be 44.4V = 12 x 3.7).

I’m not have any issues with my eTorque; start/stop works, no codes or warnings. Just wondering if this is normal.

If you’ve got JScan or AlfaOBD and wouldn’t mind checking this out, I’d appreciate it. In JScan, it’s under the Battery Pack Control Module. Probably the same for Alfa, but I’ve never used it.

I’ll try to check as I have JScan. I have been having some electrical issues for the past almost year and just started putting a noco battery maintainer/charger on my truck at least a few times a week and I haven’t had any electrical issues in the few weeks I have been doing that consistently so i definitely think my battery wasn’t consistently getting charged completely as needed

 

[jimothy]

I’ll try to check as I have JScan. I have been having some electrical issues for the past almost year and just started putting a noco battery maintainer/charger on my truck at least a few times a week and I haven’t had any electrical issues in the few weeks I have been doing that consistently so i definitely think my battery wasn’t consistently getting charged completely as needed

That’s about why I’m wondering. I work from home, so I don’t drive my truck often. I’ve now replaced my 12V battery, but I’ve the SoC and voltage of the 48V as I commented in my other post.

I wonder if those numbers are normal, or because I don’t drive enough to keep the 48V charged.

 

[GyRoCoN]

I seem to recall reading that the SOC of the 48V pack is kept intentionally low in order to extend its lifespan. sort of like how new iphones can limit the SOC to 80% if the user so desires to extend its useful life. FWIW.

 

[stevj]

The 48V battery is only charged when the engine is running to spin the generator. It is not used to cold start the engine.
For that cold start, we have a typical 12V starter powered by a typical 12V battery.

For the 12V battery, put your Battery Tender positive lead to the battery and the negative lead to a body ground point. These Rams have a monitor at the 12V battery negative terminal (the little box with wires to it at the negative terminal), so using a body ground lets the monitor stay updated to the state of charge of the 12V battery while it's on the Tender. Going straight to the negative terminal bypasses that monitor circuitry and electrical instability can result. I know - doesn't pass the common sense test, but it's true.

As a test some years ago, mostly just curiosity, I unplugged the battery monitor at the 12V battery to see how important it was: error messages on the cluster, Start/Stop disabled, no eTorque function and more.
So keeping the battery monitor "up to speed" on 12V battery state is important.

Steve