195 RBW - Relocating Battery to Inside?

[brwarrior]

Battery under the bed you say? It's like 107 this weekend so the work days are short as the 8000 BTU AC can't keep up with that nonsense. The nice thing is that a single 2000 watt inverter generator will power it. I do have to turn the unit to fan only to run the heat gun.

https://photos.app.goo.gl/8qkvqyvwZTWSAw49A

Costco had the Lion Energy UT1300 (105AH) LiFePO4 batteries on sale. They are a prismatic cell battery in a group 24 case. (Battle Born are cylindrical cell batteries.) The batteries tip the scale in the low-mid 20 lb range (24 I think). Saved like another 7 pounds and $200.

The battery is installed in a Group 24 case. The case was used and came with my previous popup. I found it hiding in the garage. An astute observe will notice the lower right corner is high. Under there is a Marine Rated Battery Fuse (60A) mounted to the positive terminal. These are from boats so there's no unprotected wiring.

The main wire is #4 and the positive goes to a disconnect mounted to the face of the bed platform. I'll try to remember to get a better pic. Then it comes back to the large fuse panel shown above the shunt. Another boating thing. I just really like Blue Sea Systems stuff. Way overkill and spendy. The negative goes through a Victron BMV-712 (I like my toys). The display is next to the main battery disconnect.

The solar charge controller (blue box above the battery) was chosen for it being RFI quiet (I'm an amateur radio operator said 2000 W inverter generator wipes out the HF bands.) It's a 16A DIY Solar Apollo. The solar inlet comes in via a connector that's like the Furion solar inlets but is 20A rated. It's mounted to the front cross member. Comes in through the bottom of the floor. It's encased in the black loom. It snaked over the top of the divider/bed support between the "rails".

Next up is to relocate the battery feed for the converter/fuse panel from the front of the trailer to that beautiful, overkill and crazy expensive fuse panel and rework the main ground from the load side of the shunt.

Other wiring to complete is hook up the 12V/ & USB outlets to the right of the bed platform and install a light in the storage compartment.

If the weights work out I may look at adding another battery and possibly a 1000w inverter. I may or may not add a Lithium converter. I store my trailer with one or two 100W solar panels attached and deploy them when I camp.

[Rolle]

I was in contact with PD. They confirmed that all their Converters Lithium profile is
14.6V constant voltage. No float.

If you stay on plugged for a long time (Weeks) that high voltage will slowly kill your Lithium battery. To avoid that it is better to disconnect the PD converter when fully charged.

[MrKABC]

Blahhhhh... so the main stumbling block is the charger.

I'm redoing the j box in the front, and thanks to @brwarrior I got my 30 gallon tank, installed it last weekend.

After I finish the rewiring I'll pull the WFCO and see what I can do about a swap or something.

[MrKABC]

Originally Posted by brwarrior

Battery under the bed you say? It's like 107 this weekend so the work days are short as the 8000 BTU AC can't keep up with that nonsense. The nice thing is that a single 2000 watt inverter generator will power it. I do have to turn the unit to fan only to run the heat gun.

https://photos.app.goo.gl/8qkvqyvwZTWSAw49A

Costco had the Lion Energy UT1300 (105AH) LiFePO4 batteries on sale. They are a prismatic cell battery in a group 24 case. (Battle Born are cylindrical cell batteries.) The batteries tip the scale in the low-mid 20 lb range (24 I think). Saved like another 7 pounds and $200.

The battery is installed in a Group 24 case. The case was used and came with my previous popup. I found it hiding in the garage. An astute observe will notice the lower right corner is high. Under there is a Marine Rated Battery Fuse (60A) mounted to the positive terminal. These are from boats so there's no unprotected wiring.

The main wire is #4 and the positive goes to a disconnect mounted to the face of the bed platform. I'll try to remember to get a better pic. Then it comes back to the large fuse panel shown above the shunt. Another boating thing. I just really like Blue Sea Systems stuff. Way overkill and spendy. The negative goes through a Victron BMV-712 (I like my toys). The display is next to the main battery disconnect.

The solar charge controller (blue box above the battery) was chosen for it being RFI quiet (I'm an amateur radio operator said 2000 W inverter generator wipes out the HF bands.) It's a 16A DIY Solar Apollo. The solar inlet comes in via a connector that's like the Furion solar inlets but is 20A rated. It's mounted to the front cross member. Comes in through the bottom of the floor. It's encased in the black loom. It snaked over the top of the divider/bed support between the "rails".

Next up is to relocate the battery feed for the converter/fuse panel from the front of the trailer to that beautiful, overkill and crazy expensive fuse panel and rework the main ground from the load side of the shunt.

Other wiring to complete is hook up the 12V/ & USB outlets to the right of the bed platform and install a light in the storage compartment.

@brwarrior, I just now got a chance to see your work. That's amazing! What *is* all of that?

• Clear box in front?
• "Wanderer" box?

I recognize the blue solar controller box, did you place it there for thermal reasons? Future expansion? There is "dead space" between the water tank and the exterior wall, any reason you wouldn't mount the controller there? I would think that placing the Safety Hub, Victron, and blue solar box there would eliminate the need for that center divider. (I don't have one and do not plan to add one)

The large cables going to the front of the trailer to plug into the battery (stock), where do you get access to them from inside the trailer to redirect them to your current setup?

Lots of questions...

[brwarrior]

Originally Posted by MrKABC

@brwarrior, I just now got a chance to see your work. That's amazing! What *is* all of that?

• Clear box in front?

The one by the Wanderer? That's a Blue Sea 6 circuit fuse panel. I have removed that as it is redundant with the new Safety Hub.

• "Wanderer" box?

That is a 30A Renogy Wanderer 30A PWM solar charge controller from my solar kit. It is not set up to charge lithium batteries with the higher voltage needed. It has been removed. (They do now make a lithium version of that controller for those that are budget minded.) I had transferred that over from my old popup.

Those two pieces of plywood at the front are now empty. I will probably remove them at some point to save a minuscule amount of weight.

I recognize the blue solar controller box, did you place it there for thermal reasons? Future expansion?

I put it there for accessibility reasons. It's hard to see in the photo but there is a small, probably 6 segment LCD that gives out information like battery and panel voltages as well as the last 6 or 7 days of solar production. The manufacturer just this week released a remote LCD display in a 3D printed ABS enclosure. Hard to keep my inner geek at bay and not buy it.

There is "dead space" between the water tank and the exterior wall, any reason you wouldn't mount the controller there? I would think that placing the Safety Hub, Victron, and blue solar box there would eliminate the need for that center divider. (I don't have one and do not plan to add one)

Are you talking about between the tank and the driver's side wall? I would think that would be pretty much inaccessible. The Safety Hub has fuses that could need to be replaced at some point. You also want the shortest possible wiring from the solar controller to your battery. My controller is wired "around" the disconnect switch so that it will charge even when the system is off. The trailer seems to pull a minimum of a 1/4 amp when nothing is on (assuming this is the CO/Propane and idle current on the radio). It pulls up to 1 amp with the fridge on.

The plywood board is there as a "bed support". I'm not a light weight and I didn't want an issue. The bed plywood looks like it's 3/8". It also gives me a way to section off the two storage areas and a nice place to mount stuff. I used a couple cable clamps on the other side that hold the stabilizer jack handle. I normally use a drill but it's come in handy when I forget my drill.

The large cables going to the front of the trailer to plug into the battery (stock), where do you get access to them from inside the trailer to redirect them to your current setup?

Lots of questions...

This is not shown in the previous photos. https://photos.app.goo.gl/Jrx7nAqjGRLGHcuw5
I don't know about your trailer but my stock battery connection cables were LONG. Those are them. I did nothing to them! They still go into that dumb front j-box and Short Stops on the front. I routed them through one of the holes in the front frame cross member. I have a snap-in bushing to protect them. IIRC, they are 3/4" conduit KO size. I also enlarged one of those holes before for the solar inlet. I just sliced the coroplast under neath and rolled it back.

I drilled down through the floor to get to the underside. If you do this, make sure you don't go dead center. I hit a 2x2 or so that runs front to back. I need to patch this hole back. It can be seen in the new photo next to where the battery wires come up through.

In the new photo you can see I've added a couple circuits to the Safety Hub. One is a 10A circuit that goes to a USB & 12V power point on the passenger side of the bed.

The other is a small circuit that goes to a small LED strip above the storage compartment door. Holy cow that thing works awesome. Lights up the entire bay better than daylight.

[MrKABC]

Still on the "to do" list! Water tank finished and bed all done now back to solving this problem...

[Bob K]

Originally Posted by MrKABC

Still on the "to do" list! Water tank finished and bed all done now back to solving this problem...

Now you've done it. I've got 2 Battleborn batteries on the way, and there's no way I'm putting $1,800 worth of batteries on the tongue, so into the "basement" of my 185RB they go.

[MrKABC]

Originally Posted by Bob K

Now you've done it. I've got 2 Battleborn batteries on the way, and there's no way I'm putting $1,800 worth of batteries on the tongue, so into the "basement" of my 185RB they go.

So the $M question remains. How to wire? How to charge? I'll also get the batteries from Battle Born but need a road map on how to proceed from here. The WFCO that comes with our trailers is inadequate.

Ideas?

[brwarrior]

I think if you are doing solar the WFCO is adequate. It will get you like 90% plus and that's fine. They don't recommend floating lithium at 100% anyways. You'll also get better life. My solar controller can take it all the way then it shuts down and won't charge again until it drops below a certain point.

If it was an issue I think I would put in a DC to DC charger with a dedicated feed from the vehicle before replacing the WFCO or adding a dedicated lithium power supply. I think that might be the way to go. Just disconnect the WFCO converter and bring 120V under the bed if you can sneak the converter in a cabinet where the WFCO already is.

My 195RB actually had enough battery wire stock that I just pulled it into the underside above the coroplast and drilled into the camper. Make sure you don't drill in the center. There's a runner down the center. I had grand ideas of a rewire then I was like why? I was already in overkill with the little panel I installed anyways.

[brwarrior]

To add on regarding the Dc to DC i did a 3000 mile trip (2700 with trailer in tow). My truck is a 17 F150 and runs an AGM because of auto start stop so it is set to charger higher than if it was flooded lead acid but lower than lithium. I did a total of (4) 500 mile days. And some other big days. The house batteries were actually a little lower at the end of those 500 mile days than when I would start the day. The truck (via my ham radio voltage display) would drop down to like 13.2VDC on those long days. I wonder if the truck would actually pull from the house battery. [emoji848]

[Bob K]

Originally Posted by MrKABC

So the $M question remains. How to wire? How to charge? I'll also get the batteries from Battle Born but need a road map on how to proceed from here. The WFCO that comes with our trailers is inadequate. Ideas?

I plan to go simplistic. I'm only looking for DC power while boondocking, so no DC to AC converter for me.

BattleBorn indicates the WFCO charger will only get the batteries to something like 80% to 90% capacity. Anytime the WFCO charger could do its thing means I have access to AC power, so I'll just use a separate lithium battery charger rather than replacing or upgrading the WFCO charger when I want to top off the batteries.

• Run connections from my new junction box up through the floor into the basement.
• Add a battery cutoff switch near the door to the basement for safety and quick access.
• Use the Victron Blue Smart 15A portable charger (lithium setting) to top off the batteries when I have access to AC power...when I actually have a need for the batteries to be at full capacity.
• Let my tow vehicle do some charging between boondocking locations. I'll have to discover what it can actually do...voltage, amperage, etc.

Next up is a portable solar panel with integrated charger that'll do lithium batteries. That'll let me manage battery power between boondock locations when I don't have access to AC power.

[ttavasc]

Originally Posted by Bob K

I plan to go simplistic. I'm only looking for DC power while boondocking, so no DC to AC converter for me.

BattleBorn indicates the WFCO charger will only get the batteries to about 80% capacity. Anytime the WFCO charger could do its thing means I have access to AC power, so I'll just use a separate lithium battery charger rather than replacing or upgrading the WFCO charger when I want to top off the batteries.

• Run connections from my new junction box up through the floor into the basement.
• Add a battery cutoff switch near the door to the basement for safety and quick access.
• Use the Victron Blue Smart 15A portable charger (lithium setting) to top off the batteries when I have access to AC power...when I actually have a need for the batteries to be at full capacity.
• Let my tow vehicle do some charging between boondocking locations. I'll have to discover what it can actually do...voltage, amperage, etc.

Next up is a portable solar panel with integrated charger that'll do lithium batteries. That'll let me manage battery power between boondock locations when I don't have access to AC power.

Make sure and do your research here. I've seen numerous posts where folks have burned out their alternators charging the Lithium batteries off the TV. While I don't yet have Lithium batteries, I have been upgrading and enhancing my set up to support them in the future. For charging from the TV it looked to me like a DC-DC charger was the recommended method so I installed a Victron Energy Orion-TR Smart 12/12-30 DC-DC charger earlier this season. I've had a couple of opportunities to use it with my Trojan T-125's and it does a fantastic job. Redarc is another brand I see highly recommended for DC-DC charging and Lithiums.

Another option would be Li-BIM (Lithium Battery Isolation Manager) which will cycle the charging on/off regularly to avoid overheating the alternator.

[Bob K]

Originally Posted by ttavasc

Make sure and do your research here. I've seen numerous posts where folks have burned out their alternators charging the Lithium batteries off the TV.

Great advice.

The 2017 Tacoma with tow package has a high output 130-amp alternator. The manual is, of course, way short on details about how the 12v power circuit is controlled through the 7-pin connector. That wire is only about 10 gauge, so there has to be a current-limiting component of some sort on that circuit. Otherwise, depleted trailer house batteries could easily draw more current than that 10 gauge wire can tolerate and cause it to either burn up or blow a fuse. Of course, the fuse box diagrams don't indicate what fuse controls the trailer power circuit, so I can't check to see what the circuit is rated for.

In my setup, I'm not concerned about overtaxing the alternator. Rather, I'm concerned about undertaxing the alternator. In other words, I'm concerned that the regulator on the trailer connector 12v power circuit may limit the output to the point that it can't effectively charge 2 batteries in a reasonable amount of time.

I need to get my voltmeter out (and perhaps invest in a DC ammeter...my voltmeter only measures up to 10 amps) and do some checking to see how much the regulator on that circuit actually permits.

[Bob K]

Originally Posted by brwarrior

The house batteries were actually a little lower at the end of those 500 mile days than when I would start the day. The truck (via my ham radio voltage display) would drop down to like 13.2VDC on those long days. I wonder if the truck would actually pull from the house battery.

Mmm...electrical theory. A tasty topic.

The trailer is indeed connected to the same 12v positive and negative circuits as the TV through the trailer connector.


Unless there's a diode or smart switch in that 12V POWER circuit, I'd imagine the TV battery could indeed accept electrons from the trailer house battery. Without a diode or a switch, they'd basically just be two batteries connected in parallel. I confirmed that my 2017 Tacoma 12v POWER trailer circuit is switched: The 12v POWER circuit to the trailer isn't live until the TV is key-on.

Is your TV a newer vehicle? Modern vehicles adjust alternator output based on the charging needs of the TV battery. Once the TV battery is charged, the electrical system reduces voltage and current. 13.2v just happens to be a perfect float charge voltage.

13.2v, however, isn't enough voltage to charge a battery efficiently, so if your TV electrical system has reduced output to 13.2v on the trailer connector 12v POWER circuit, then your house batteries aren't getting enough juice to charge.

I'm inclined to believe there has to be a switch or regulator of some sort on the 12v POWER circuit in any modern trailer connector. Otherwise, connecting the TV to a trailer with a depleted battery (or vice versa) would be like connecting little 10 gauge jumper cables between the two batteries: The depleted battery would pull so much amperage that it would burn up the wire or blow a fuse.

Interestingly, with the motor on in my TV, the 12v POWER circuit only registers 10v. I need to do some more testing with the trailer connected to see if there are further electronics on the 12v POWER circuit that allow it to ramp up current and voltage when it detects a need.

[ttavasc]

Originally Posted by Bob K

Great advice.

The 2017 Tacoma with tow package has a high output 130-amp alternator. The manual is, of course, way short on details about how the 12v power circuit is controlled through the 7-pin connector. That wire is only about 10 gauge, so there has to be a current-limiting component of some sort on that circuit. Otherwise, depleted trailer house batteries could easily draw more current than that 10 gauge wire can tolerate and cause it to either burn up or blow a fuse. Of course, the fuse box diagrams don't indicate what fuse controls the trailer power circuit.

In my setup, I'm not concerned about overtaxing the alternator. Rather, I'm concerned about undertaxing the alternator. In other words, I'm concerned that the regulator on the trailer connector 12v power circuit may limit the output to the point that it can't effectively charge 2 batteries in a reasonable amount of time.

I need to get my voltmeter out (and perhaps invest in a DC ammeter...my voltmeter only measures up to 10 amps) and do some checking to see how much the regulator on that circuit actually permits.

I wouldn't expect much through the 7-pin - I generally see just a few amps - enough to maintain a charged battery but it isn't going to do much for a depleted battery that needs a good charge. When I installed the Victron DC-DC charger I ran a dedicated 2 gauge wire from the truck battery to the rear bumper, then 6 gauge on the trailer side for the umbilical as that was the largest wire the Victron will accept. Under ideal temperature conditions it will provide 40 amps - so far I've seen a little over 38 amps charge current on my BMV-712 monitor from it.

Something else to keep in mind is most newer vehicles come with "Smart Alternators" that have highly variable voltage depending on conditions. A DC-DC charger will boost or reduce the voltage to maintain it at a constant stable value as defined by the charging profile. In my case I configured a custom charge profile based on the data Trojan publishes for the T-125 bulk, absorption and float phases. On the Victron Orion-TR Smart series there is a preset charge profile specifically for LiFePo4.

[brwarrior]

Originally Posted by Bob K

Mmm...electrical theory. A tasty topic.

The trailer is indeed connected to the same 12v positive and negative circuits as the TV through the trailer connector.
Attachment 63221

Unless there's a diode or smart switch in that 12V POWER circuit, I'd imagine the TV battery could indeed accept electrons from the trailer house battery. Without a diode or a switch, they'd basically just be two batteries connected in parallel. I confirmed that my 2017 Tacoma 12v POWER trailer circuit is switched: The 12v POWER circuit to the trailer isn't live until the TV is key-on.

Is your TV a newer vehicle? Modern vehicles adjust alternator output based on the charging needs of the TV battery. Once the TV battery is charged, the electrical system reduces voltage and current. 13.2v just happens to be a perfect float charge voltage.

13.2v, however, isn't enough voltage to charge a battery efficiently, so if your TV electrical system has reduced output to 13.2v on the trailer connector 12v POWER circuit, then your house batteries aren't getting enough juice to charge.

I'm inclined to believe there has to be a switch or regulator of some sort on the 12v POWER circuit in any modern trailer connector. Otherwise, connecting the TV to a trailer with a depleted battery (or vice versa) would be like connecting little 10 gauge jumper cables between the two batteries: The depleted battery would pull so much amperage that it would burn up the wire or blow a fuse.

Interestingly, with the motor on in my TV, the 12v POWER circuit only registers 10v. I need to do some more testing with the trailer connected to see if there are further electronics on the 12v POWER circuit that allow it to ramp up current and voltage when it detects a need.

Truck is a '17 F150. It's pretty smart. Knows when a trailer is hooked up and will keep like 5 in memory for settings. Not smart enough to know WHICH trailer is hooked up though. Give 'em a few years and that might happen. The alternator does adjust output. Usually runs 14.2 when just started. Before this big trip I had never actually seen it down to 13.2 on the radio. (For the hams it's a Yaesu FTM-400XDR and I have it display voltage instead of time.)

I don't think Ford would put a diode that could carry up to 30 amps, if the system can even do that. Most I saw going into the battery is 9amps when the truck is first started so it is pushing 14.2VDC and quickly drops down. The trailer runs anywhere from 250mA to about 2 amps with the fridge on (has a fan or two).

I am seriously thinking about running a secondary charge line for a DC-DC just because of the alternator and wiring issue. It would also make using the Viair easier. It's one of those "how much do I need vs want" and of course, how much does it weigh?

[Bob K]

Originally Posted by brwarrior

I don't think Ford would put a diode that could carry up to 30 amps, if the system can even do that. Most I saw going into the battery is 9amps when the truck is first started so it is pushing 14.2VDC and quickly drops down. The trailer runs anywhere from 250mA to about 2 amps with the fridge on (has a fan or two).

Makes one wonder what purpose the stupid 12v POWER circuit to the trailer serves if modern alternators are basically going to render that circuit useless.

[brwarrior]

Originally Posted by Bob K

Makes one wonder what purpose the stupid 12v POWER circuit to the trailer serves if modern alternators are basically going to render that circuit useless.

Well namely they are trying to manage the trucks battery which is AGM. Needs a little more voltage than flooded lead acid but not as much as LiFePO4. Typically trailer batteries have been flooded so it would work ok and they can take only so much power. Lithium is like a 17 year old high school athlete that eats everything in the house.

[01tundra]

The factory 12v+ wire on our 2017 2500HD was only 12AWG.

Even with our smaller 12/12-18 DC charger the voltage drop was going to be incredibly high. I ran dedicated 4AWG 12V +/- from one of the batteries back to an Andersen plug and made a new charger pigtail for the charger in the trailer. I took 4AWG back by the charger and landed on power posts so I could drop down to 6AWG to the charger......sure wish Victron would've made the lugs larger.

Even though I can disable the charger through the Victron app, I still wired in a battery switch to be able to hard disconnect the truck from the trailer when we stop for food or fuel. The LiFePO4 batteries are at a higher resting voltage than the truck's lead acid batteries, so the truck could pull the trailer batteries down.

The 18A DC-DC charger will output 25 amps, so at 87% efficiency it's pulling around 29A on the TV side.

Our other two charging options are a 200W solar suitcase and a PD4655L Wildkat converter.

[ttavasc]

Originally Posted by 01tundra

The factory 12v+ wire on our 2017 2500HD was only 12AWG.

Even with our smaller 12/12-18 DC charger the voltage drop was going to be incredibly high. I ran dedicated 4AWG 12V +/- from one of the batteries back to an Andersen plug and made a new charger pigtail for the charger in the trailer. I took 4AWG back by the charger and landed on power posts so I could drop down to 6AWG to the charger......sure wish Victron would've made the lugs larger.

Even though I can disable the charger through the Victron app, I still wired in a battery switch to be able to hard disconnect the truck from the trailer when we stop for food or fuel. The LiFePO4 batteries are at a higher resting voltage than the truck's lead acid batteries, so the truck could pull the trailer batteries down.

The 18A DC-DC charger will output 25 amps, so at 87% efficiency it's pulling around 29A on the TV side.

Our other two charging options are a 200W solar suitcase and a PD4655L Wildkat converter.

Even though the Victron Orion-TR devices have an ignition detection feature I went the rather old-school route of installing an ignition-switched 85 amp continuous duty solenoid next to the truck battery which ensures there is no opportunity for the truck battery to be drained when connected but not running. I also wired in a button for the remote on/off feature for maintenance and troubleshooting purposes.

Outside of the lithium batteries you have installed our systems are very similar as I also have a 200w solar suitcase with VE MPPT 100/20 controller and a PD4655VL converter. We'll find out how well things work next week as we head out for about 10 days without hookups.