[Build Walkthrough] Custom Dual Battery Setup - REDARC BCDC alpha 50r

[mvilla]

After comparing a few popular options—like the American Adventure Lab rear storage battery tray—I opted to build a fully custom dual battery setup in my Bronco using the DV8 expanded cargo storage box. The AAL tray was solid, but I went custom for two key reasons:

1. I can fit 5x 20Ah batteries (vs 4 with the AAL), giving me 100Ah total.
2. My design allows the enclosure to fully close, which the AAL solution cannot do when loaded.

The result is a compact, serviceable 12V system that powers all my gear cleanly and reliably—and it’s future-ready for solar and cooling upgrades.

Build Goals:

• Fully self-contained auxiliary power with clean install
• Enough juice to run fridge, lighting, device charging, and Starlink
• Modular for future upgrades (solar, cooling)
• Easy access for troubleshooting and expansion

System Overview:

• Battery Bank: 5x Amped Outdoors 20Ah LiFePO₄ (wired in parallel = 100Ah)
• Charger: Redarc BCDC Alpha 50R, mounted on the driver-side rear window molle panel
• Mounting: Custom 3D-printed battery trays with roller cam straps, secured in the DV8 expanded cargo compartment
• Power Distribution:
  • Blue Sea fuse block mounted on the passenger-side rear window molle panel for loads
  • Custom 3D-printed fuse block with copper bus bar located inside the enclosure for internal power routing

Connected Loads:

• ICECO APL55 dual-zone fridge
• Mabett rear cargo light
• 4x USB-C outlets
• Baja Designs dome lights (1 amber, 1 red)
• Starlink Mini
• Blue Sea OLED temperature monitor

Expandability:

• Cooling: Space is tight and the enclosure gets hot. I’m planning to add a heat-activated blower fan to keep things cool
• Solar: Pre-wired with an Anderson input for solar charging via the Redarc Alpha’s solar input
• Inverter: The system is ready to accept an inverter if I need it, but so far the in cabin inverter has been fine

Happy to answer questions or help anyone working on a similar project. Feel free to ask about any of the components, 3D-printed parts, or design choices.



****Update****
To manage temperatures I added a W1209 controller and a blower fan to the enclosure.

• Blower Fan: 120mm x 120mm radial blower rated at 31.6 CFM
• Controller: W1209 digital thermostat wired to trigger the fan

Everything fits nice and snug. I have them mounted with Velcro to the lid of the enclosure for now. I will reassess later on if I need to hard mount them, but for now this is ok.

The W1209 thermostat can be programmed to activate power to the fan when the temperature reaches a certain threshold. It’s set to kick on at 110 degrees and turn off at 100.

I’ll post some performance results after a few long drives.

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[Nibroc99]

This is a pretty darn incredible build and an excellent write-up. You've scratched my OCD itch big time.
How's it working with the solar panels? Are they providing a good amount of charge? Also, how long is the standby (engine off) time with your loads running? Eight to ten years? Joking aside, though, I am curious how long it lasts before needing to recharge, and how long does it take to get back up to a full charge from the engine and solar panel combo?

 

[mvilla]

This is a pretty darn incredible build and an excellent write-up. You've scratched my OCD itch big time.
How's it working with the solar panels? Are they providing a good amount of charge? Also, how long is the standby (engine off) time with your loads running? Eight to ten years? Joking aside, though, I am curious how long it lasts before needing to recharge, and how long does it take to get back up to a full charge from the engine and solar panel combo?

I haven’t installed solar yet and haven’t drained the battery completely. I let it sit for 3 days after installing and there was still some juice left by the time I started driving again. It took maybe one and a half to two hours to get up to 100% charge.

 

[B22-2023]

After comparing a few popular options—like the American Adventure Lab rear storage battery tray—I opted to build a fully custom dual battery setup in my Bronco using the DV8 expanded cargo storage box. The AAL tray was solid, but I went custom for two key reasons:

1. I can fit 5x 20Ah batteries (vs 4 with the AAL), giving me 100Ah total.
2. My design allows the enclosure to fully close, which the AAL solution cannot do when loaded.

The result is a compact, serviceable 12V system that powers all my gear cleanly and reliably—and it’s future-ready for solar and cooling upgrades.

Build Goals:

• Fully self-contained auxiliary power with clean install
• Enough juice to run fridge, lighting, device charging, and Starlink
• Modular for future upgrades (solar, cooling)
• Easy access for troubleshooting and expansion

System Overview:

• Battery Bank: 5x Amped Outdoors 20Ah LiFePO₄ (wired in parallel = 100Ah)
• Charger: Redarc BCDC Alpha 50R, mounted on the driver-side rear window molle panel
• Mounting: Custom 3D-printed battery trays with roller cam straps, secured in the DV8 expanded cargo compartment
• Power Distribution:
  • Blue Sea fuse block mounted on the passenger-side rear window molle panel for loads
  • Custom 3D-printed fuse block with copper bus bar located inside the enclosure for internal power routing

Connected Loads:

• ICECO APL55 dual-zone fridge
• Mabett rear cargo light
• 4x USB-C outlets
• Baja Designs dome lights (1 amber, 1 red)
• Starlink Mini
• Blue Sea OLED temperature monitor

Expandability:

• Cooling: Space is tight and the enclosure gets hot. I’m planning to add a heat-activated blower fan to keep things cool
• Solar: Pre-wired with an Anderson input for solar charging via the Redarc Alpha’s solar input
• Inverter: The system is ready to accept an inverter if I need it, but so far the in cabin inverter has been fine

Happy to answer questions or help anyone working on a similar project. Feel free to ask about any of the components, 3D-printed parts, or design choices.

What is the device that the temp monitor is plugged into?

 

[mvilla]

What is the device that the temp monitor is plugged into?

It’s a blue sea panel and a mount found here:

The 12 Volt Accessory Panel Mount... https://www.amazon.com/dp/B0B9QFWVNP?ref=ppx_pop_mob_ap_share

Blue Sea Systems 4366... https://www.amazon.com/dp/B07PP1V3L5?ref=ppx_pop_mob_ap_share

 

[Brian_B]

Very nice build!

 

[Kevin Scarbel]

I would have installed a (Dragonfly Energy) Battle Born 270Ah GC3 though.

 

[mvilla]

I would have installed a (Dragonfly Energy) Battle Born 270Ah GC3 though.

One of the goals was to keep it located in the cargo space so as not to take up room. That battery looks nice, but it would definitely not fit in there.

I spent a lot of time trying to find batteries that would fit and give me the most capacity and settled on these ones from amped outdoors (same ones used with AAL setup)

 

[Dugout]

Great write-up and setup.

 

[ElDuderino]

Great write up!

A parts list would be cool, also 3d print files? I'm currently using a power station but it's a pain to lug around and adds too much weight.

Without the loads - besides the temp monitor, what was a rough estimate on cost?

Also, in your wiring diagram you have a blue line running from the bcdc alpha, where is that running to? I see some writing on the line, but the resolution of the photo makes it blurry when zoomed.

 

[jtgensler]

Nice Setup, I'm jealous!

I'd love to do something similar eventually.
For now I'm just rolling with this big ole 100ah LiFePO4 I got for $150 & I'm using 12v from the outlet to charge a tiny bit while driving & I plug a charger in 2x a week to top it off.
It's only powering a starlink mini during the day, so it lasts about 4 days between needing charged.

 

[mvilla]

Great write up!

A parts list would be cool, also 3d print files? I'm currently using a power station but it's a pain to lug around and adds too much weight.

Without the loads - besides the temp monitor, what was a rough estimate on cost?

Also, in your wiring diagram you have a blue line running from the bcdc alpha, where is that running to? I see some writing on the line, but the resolution of the photo makes it blurry when zoomed.

Item	Qty	Cost
Redarc BCDC Alpha50-R (BCDC12050R)	1	$949.00
Amped Outdoors 20Ah LiFePO4Battery	5	$595.00
Blue Sea 5025 Fuse Block	1	$45.00
DV8 Expanded Cargo Storage Box	1	$300.00
RollerCam 2’ x 0.75” Straps	5	$40.00
12V Accessory Panel Mount (USB + 12V)	1	$95.96
600A Marine Bus Bar (Red & Black, 4 M10 Studs)	1	$75.99
Blue Sea 4366 Water-Resistant Accessory Panel	1	$85.02
Duco ABS Plastic Sheet 1/4” x 12” x 24”	1	$26.35

Total: $2,212.32

This doesn’t include wiring, connections, fuses, etc but plan to spend about $200 on that.

I can share the 3D print files if you want. Just shoot me a DM.

The blue wire is the ignition source. I routed it to the fuse box under the hood. I connected it to the fuse for the 360 camera.

 

[mvilla]

Nice Setup, I'm jealous!

I'd love to do something similar eventually.
For now I'm just rolling with this big ole 100ah LiFePO4 I got for $150 & I'm using 12v from the outlet to charge a tiny bit while driving & I plug a charger in 2x a week to top it off.
It's only powering a starlink mini during the day, so it lasts about 4 days between needing charged.

How do you like the badlands jack? Considering getting one but not sure if I want to occupy more space in the cargo. Where are your wires going to behind the cargo panel?

 

[jtgensler]

How do you like the badlands jack? Considering getting one but not sure if I want to occupy more space in the cargo. Where are your wires going to behind the cargo panel?

I love the jack. I copied a set of mounts from 911 Motorsport & just made them myself.
I figure it's easy enough to take out when you don't need it.

The one wire is running to my starlink, mounted on an overhead molle. The other is just hiding the extra wire for the 12v charger behind the trim.

 

[ElDuderino]

Item	Qty	Cost
Redarc BCDC Alpha50-R (BCDC12050R)	1	$949.00
Amped Outdoors 20Ah LiFePO4Battery	5	$595.00
Blue Sea 5025 Fuse Block	1	$45.00
DV8 Expanded Cargo Storage Box	1	$300.00
RollerCam 2’ x 0.75” Straps	5	$40.00
12V Accessory Panel Mount (USB + 12V)	1	$95.96
600A Marine Bus Bar (Red & Black, 4 M10 Studs)	1	$75.99
Blue Sea 4366 Water-Resistant Accessory Panel	1	$85.02
Duco ABS Plastic Sheet 1/4” x 12” x 24”	1	$26.35

Total: $2,212.32

This doesn’t include wiring, connections, fuses, etc but plan to spend about $200 on that.

I can share the 3D print files if you want. Just shoot me a DM.

The blue wire is the ignition source. I routed it to the fuse box under the hood. I forget which fuse, but I’ll double check and update.

Great info, thank you. Not too expensive. I will message you for 3d files. What gauge wiring are you using? I'm not too good with electrical but this seems pretty straight forward.

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