DC to DC Charger

[mattoest]

Does anyone have experience connecting a DC to DC Charger (for a lithium battery) to a 1500 with etorque? Does it present any problems, or work like it would with a smart alternator?

 

[Drewster]

A lithium battery charger is not intended for use with car batteries. If you're looking to trickle charge it in your garage, just get a trickle charger that can work with AGM batteries.

If you're trying to do something bizarre while you're driving, let us know how it goes, but don't be surprised if your $1500 battery pack throws some error codes

 

[mattoest]

A lithium battery charger is not intended for use with car batteries. If you're looking to trickle charge it in your garage, just get a trickle charger that can work with AGM batteries.

If you're trying to do something bizarre while you're driving, let us know how it goes, but don't be surprised if your $1500 battery pack throws some error codes

Thanks. For context,, I will be pulling a travel trailer with lithium batteries. They will not charge fully off the 7-pin while driving. This will be made worse by the voltage drop from a ~40 foot distance to the trailer batteries in the rear. A DC to DC charger like the Orion 12/12 30 will accept any incoming voltage down to 10v and step it up for charging the lithium batteries while driving. I'm just wondering, to the point you made, if that will cause issues with the etorque generator. I would attach the charger wires to the 1500 battery, so I think the system would just interpret it like any other load, but it can use up to 30 amps, which would be like adding a whole additional high output audio system to the truck.

 

[Zeronet]

First let me say, I don’t have the eTorque.

I get 15 amps at above 14 volts off the 7 pin at my lithium batteries (Victron battery monitor), even at idle. When I rev the engine the amps stay about the same so the output to the 7 pin may be regulated. Provides a decent charge but it would take a very long drive to fully charge my 200ah batteries if they were running low. The batteries are mounted in the front basement.

You may get get roughly double the charge you are currently getting from the 7 pin with a 30 amp DC to DC charger. But if you’re tying into the existing trailer wiring, which is usually undersized, your wire losses will likely rise due to more heat being generated with the higher amps. Do a search on YouTube if you haven’t already. Several RVers are using a similar setup but I haven’t seen any with eTorque.

 

[mattoest]

First let me say, I don’t have the eTorque.

I get 15 amps at above 14 volts off the 7 pin at my lithium batteries (Victron battery monitor), even at idle. When I rev the engine the amps stay about the same so the output to the 7 pin may be regulated. Provides a decent charge but it would take a very long drive to fully charge my 200ah batteries if they were running low. The batteries are mounted in the front basement.

You may get get roughly double the charge you are currently getting from the 7 pin with a 30 amp DC to DC charger. But if you’re tying into the existing trailer wiring, which is usually undersized, your wire losses will likely rise due to more heat being generated with the higher amps. Do a search on YouTube if you haven’t already. Several RVers are using a similar setup but I haven’t seen any with eTorque.

Thanks for the input. I appreciate it. If I go with this, I will run a 6AWP connection with an anderson connector, which is the largest gauge wire the Orion will accept. I am putting in a Victron multiplus inverter/charger, plus solar, with 3 100ah batteries, so I will need to modify or replace a fair amount of the trailer electrical system between shore power, batteries and the power center panel. I will need to install bus bars behind the trailer power center panel to run the trailer systems that aren't on the panel (e.g., tongue jack) to. I've closely studied the plans on explorist.life and am more or less using one of the sponsor's plans. Because of where I need to store the trailer, I won't be mounting the solar to the roof, so I will need to deploy at the campsite and can't solar charge on the road, hence the desire to top off the batteries on the road with the DC to DC charger instead of needing to run the generator to do that when I get to the campsite.

 

[Zeronet]

Sounds like you’ve done your research and will have a very nice system.

I’ve got 600 watts of solar on the roof and a 2000 watt inverter. Like you, I understood that the factory wiring just wasn’t up to the task. I too have replaced much of the wiring.

While driving, between the truck contributing 15 amps and the solar producing 15-35 amps I get a good amount of power. However I don’t like to travel with the refrigerator on propane, I run it off the inverter while driving and switch over to propane when we arrive at our destination. It’s power hungry and consumes 27.5 amps, it runs almost constantly. Still some juice left to charge the batteries if needed.

The good news is with 600 watts of solar on the roof the batteries almost never get below 40% overnight and are fully charged the following day. No need for a generator, ever, unless we want air conditioning.

Might I ask why you’re not mounting solar on the roof? I store my trailer in my barn and just hit the breaker for the panels, then turn off the battery disconnect. I leave a dehumidifier running inside off ac power. Keeps it fresh inside.

Best of luck on your project. Really interested in hearing your impressions once you’ve got it up and running. Particularly the Multiplus. Maybe for my next camper.

 

[mattoest]

Sounds like you’ve done your research and will have a very nice system.

I’ve got 600 watts of solar on the roof and a 2000 watt inverter. Like you, I understood that the factory wiring just wasn’t up to the task. I too have replaced much of the wiring.

While driving, between the truck contributing 15 amps and the solar producing 15-35 amps I get a good amount of power. However I don’t like to travel with the refrigerator on propane, I run it off the inverter while driving and switch over to propane when we arrive at our destination. It’s power hungry and consumes 27.5 amps, it runs almost constantly. Still some juice left to charge the batteries if needed.

The good news is with 600 watts of solar on the roof the batteries almost never get below 40% overnight and are fully charged the following day. No need for a generator, ever, unless we want air conditioning.

Might I ask why you’re not mounting solar on the roof? I store my trailer in my barn and just hit the breaker for the panels, then turn off the battery disconnect. I leave a dehumidifier running inside off ac power. Keeps it fresh inside.

Best of luck on your project. Really interested in hearing your impressions once you’ve got it up and running. Particularly the Multiplus. Maybe for my next camper.

I'm in a pretty dense urban area (just a couple blocks north of the City of Chicago) and there is no way to store the trailer at my home. 30 foot parking spots with good access and a half way secure neighborhood are at a premium. I found an affordable one but it just happens to be immediately adjacent to an overpass and I have concerns about stuff getting kicked up by passing traffic, or deliberately thrown by kids, onto the panels and damaging them. I purchased 3 Renogy 175w flexible panels. They are only 6 lb ea and easy to deploy manually, plus the flexibility make it easy to store them in the pass-through. Between the grommets and adhesive they can be put on the roof, and I may still do it, I just haven't gotten comfortable with it yet. Thanks

 

[marcopollo]

Did you ever get a DC-to-DC converter in your trailer hooked up to your RAM 1500 eTorque? I'm looking to do the same to charge a 200aH LiFePO4 battery in my travel trailer. Does anyone know how many amps my RAM1 1500 currently supplies at the 7-pin? Do I even need a DC-to-DC to boost the amperage?
Thanks for any input.

 

[PedroD]

I am exploring charging my four LionEnergy LiFePO4 batteries in my trailer while driving using a Renogy 60A DC-DC charger. It seems as simple as running a AWG2 from the battery terminal in the RAM to an Anderson clip mounting in the bed. Then connecting that to an extension through the camper to the batteries. My concern is the eTorque 48V system. Would I create any issues while driving by adding the 60A draw to the truck?

 

[marcopollo]

Well, my plan is to install a Renogy 40A DC-to-DC charger to a 280Ah LiFePO4 battery in my trailer with AWG4 wires running from my RAM1500 battery to Anderson jacks and then into my trailer. Just waiting on parts...

 

[Bonzma]

Does anyone have experience connecting a DC to DC Charger (for a lithium battery) to a 1500 with etorque? Does it present any problems, or work like it would with a smart alternator?

Did you ever get a DC-to-DC converter in your trailer hooked up to your RAM 1500 eTorque? I'm looking to do the same to charge a 200aH LiFePO4 battery in my travel trailer. Does anyone know how many amps my RAM1 1500 currently supplies at the 7-pin? Do I even need a DC-to-DC to boost the amperage?
Thanks for any input.

Also wondering if you guys had any luck with this. I have a 100ah lithium that I will be using to power a diesel heater And really just wanted it to run off pin 7 while I’m driving. My concern is it appears I’m only getting 14.1 ish at the trailer on pin 7. If resting voltage is 14.6 on the lithium it wouldn’t even use the truck and would likely backfeed to the truck Battery? ill keep researching but wanted to know if you made any progress. I also have the etorque

 

[Airstreamin]

I see this is an old post… im wondering how that worked. I put 2 Lion UT1300s in my Airstream ( 400 W solar) couple of years ago. Never thought about charging from the 7 Pin. The solar more than covers it and the batteries are fully charged by noon. Since we’re heading to the East Coast this summer, I won’t have sun everywhere all the time. Hence the interest in the DC-DC charger. in Researching, I found that the lithiun will draw a lot of power from the 7 pin connect given half a chanice. My 7 Pin 12 V feed 30A fuse has been blown a long time and I never noticed.

 

[Patriot22]

Any updates would be appreciated. I also have the etorque and would like to charge my lithium batteries while driving (4 x 100 amph lithium phosphate ). Something was mentioned about the 7th pin putting out 15amps. My research shows it is only about 1-2 amps from youtube videos that measured the output hence the need for the dc to dc charger. I would love to find out what everyone else has done.

 

[kapinallinen2]

Any updates would be appreciated. I also have the etorque and would like to charge my lithium batteries while driving (4 x 100 amph lithium phosphate ). Something was mentioned about the 7th pin putting out 15amps. My research shows it is only about 1-2 amps from youtube videos that measured the output hence the need for the dc to dc charger. I would love to find out what everyone else has done.

The 7-pin is fused at 30 amps. Fuse 01, assembly, power distribution center, interior.

 

[SnowBlaZR2]

Any updates would be appreciated. I also have the etorque and would like to charge my lithium batteries while driving (4 x 100 amph lithium phosphate ). Something was mentioned about the 7th pin putting out 15amps. My research shows it is only about 1-2 amps from youtube videos that measured the output hence the need for the dc to dc charger. I would love to find out what everyone else has done.

It's more than 1-2 amps. We have a 12V refrigerator and a 12V outdoor refrigerator/freezer that we're running as a freezer only. Those are generally drawing about 8 amps total when they're both on. We also have a few amps of constant draw from CO alarm, radio, etc. We've rarely gone below 100% on a travel day, and if we do it's because we're using the water pump, fans, charging devices, etc. during a longer stop.

If we do a Harvest Host or parking lot stay, we drain the batteries, and they're always higher when we arrive than when we left.

We're still likely going to end up installing a DC-DC charger and some solar.

 

[Patriot22]

I have not measured it. I am going off a youtube video with someone that ended up installing the dc to dc charger in a truck with a plug to use as a fifth wheel. He measured the actual amperage that was being received over the long run on the current wire, which is NOT that big. Everyone installing dc to dc chargers are using 4 or 6 guage wire. I think the truck has maybe 12?

I am in discussion with a company, unplugged , in sanford florida to upgrade my system. There question is whether the system can handle the 30 amp draw on the etorque. They have no experience with it.

 

[HookedonRam]

So, is there a way to install Renogy's dc-to-dc mppt charger to an etorque hemi v8?

 

[PeterB]

I'm also installing the Renogy dcdc mppt charger in my 2021 etorque and any help would be greatly appreciated to answer just one more question: a wire needs to be attached to the ignition circuit to activate this Renogy charger, but what fuse can be used for this? None of the fuse labels in the owner's manual tables for the engine compartment Power Distribution Center and the Interior Power Distribution Center say anything about "ignition." In the engine compartment, fuse F01 is a 25 amp for the "Fuel Pump Motor" and could this be used to install a fuse tap for the ignition circuit?

Another thread has quite a bit on this topic (2022 Limited alternator) but there's nothing related to my specific question here. Again, any help would be greatly appreciated.

 

[boogielander]

So if it's not too late for OP (and for future reference) here is how I did mine with e-torque.

First off, let me say I did NOT use Renogy DC-DC mppt charger. I used a Victron Isolated DC-DC charger/ converter instead. I found that to be the simplest solution to this problem. I also have this inside my cab instead of on a trailer ( I dont own/ tow a trailer... but that may change in the future) since everything I need for camping/ overlanding is self-contained to my truck. I have a 3kw EcoFlow setup in the back seat that is charged by Victron, so I run the ign wire to the fuse box inside. Even though my application is different, the principle and the way it works are the same.

@PeterB I do have something hooked to engine bay fuse box that is IGN switched. I don't have my truck right now and I forgot which one it is. I will check for you tomorrow when I drive the truck to work. Alternatively, you can also use a multimeter to find it.

Now, with all that out of the way. Let's start with how I did it.

Parts needed:

• Blue Sea 60A circuit breaker (you can use inferior Chinese branded ones if you want, but I strongly recommend not. Chinese branded ones or Chinese made ones that are NOT made made for US or EU companies have a lower energy rating)
• 8 Gauge Wires, power and ground
• Spool of 14 Gauge Wire and Micro2 Fuse Tap
• 5A Micro2 fuse
• Wire Looms
• Ring Terminal Connectors for both 8Ga wires and 14ga wires.
• Victron Isolated DC-DC Chargers
• Blue Sea Bus Bar and Fuse Block w/ Ground (both optional, but recommended)

Brief overview of how I did it.

• Decide and mount each component you will be using, such as the battery, the DC-DC charger, fuse block/ bus bar, etc.
• I ran enough 8ga wires from the battery to where I want to install my Fuse Block with Ground, both power and ground. Also run one 14ga wire for IGN and add the fuse tap for the applicable fuse slot.
• I then added the circuit breaker for the power side near the battery. This will serve as an on/ off switch and a layer of protection in case something goes wrong, it will cut itself out and not affect the functionality of the truck.
• Sleeve the entire harness and secure it.
• Run one 14g power and ground from the fuse block w/ ground to the Victron. This is actually the preferred way for 2 reasons: 1)You can add a solar controller later down the line and hook it to the fuse block, if you choose to. 2)You will have a secondary safety (fuse) here in case something fails.
  • 14g is ample for Victron's usage. Victron is actually a regulator that can step 12v input up to 24v or even 48v output if faster charging speed is needed.
  • You do not need to use a 8g wire for Victron because you're not drawing power directly from the alternator. You're actually drawing from the battery itself, so there's no power surge or anything like that to consider.
• Connect the IGN trigger and download the Victron app. Switch to "charger" mode and enable engine shut down disable.
  • Charger mode is the only mode that allows engine shutdown detection
  • Engine shutdown detection will detect no current being sent through IGN, and therefore will isolate the output. That way you will not draw any power from your starter battery.
• Also enable smart alternator and start up delay. That will give some time after starting the vehicle before Victron starts to draw power to avoid that initial start up current hike.

Normally, it is NOT recommended to run dual battery setup with different chemistry batteries. However, with smart converter like Victron that has dedicated profiles for different house battery (secondary battery), I think it should be OK.

Benefits of running the Victron:

• Smart controller
  • Built in profiles, engine shutdown detections, charging cycles, etc
• Fast charging
  • With my setup and using XT60i cable as output cable to my Ecoflow, I can get 200w of charge rate. with output set to 13.3V at 15amp. I get 210w of charge rate when output is set to 14v at 15amp. Not much difference. But with another unit (that I have sitting in the garage), I can bump it up to 24v @ 15amp output netting me about 360w of power.
• All-in-one design
  • This is the only thing you will need in addition to the battery.
  • Smart phone integration
    • All settings are done via app and you can monitor it any time.

I will have a detailed write up some time in the future, when I get to taking photos lol


Additional Info:

• Lithium batteries require higher voltage (high 13s and low 14s) to be happy. E-torque does not constantly put out that much. In fact, e-torque keeps the starting battery voltage relatively low at high 12s to low 13s. Those are not enough to keep lithium battery happy. Therefore, a smart DC-DC charger is needed to manage the charging. This is exactly why a lot of "dumb" dual battery systems will not work with ours unless both batteries are switched to the same chemistry.

 

[PeterB]

Boogielander, thanks very much for the detail, and please do let me know which engine bay IGN fuse number you connected to and the description of this fuse from the owner's manual (just because our different model year trucks might have a slightly different fuse layout and fuse numbers).

I encountered the exact problem you did with insufficient voltage to charge my camper battery from the starting battery. I use portable solar panels so the Renogy DCDC with mppt allows me to both direct charge and solar charge via one device that has similar capabilities as your Victron.

And the only place I can find to mount this charger is in the very back of my camper, so I'm using 4 AWG wire, and other than this our setups are very similar.

I think that several readers of this forum would appreciate your detailed writeup and photos when you get to it.