Our Auxiliary Power Supply…

Our original plan for this trip was to use a 12VDC refrigerator but bad planning on my part meant if we ordered one it would not arrive in time.

The core of this system is built upon a SOK Battery 12VDC/100A LiFePO4 battery. Yes, it is expensive, but we needed a battery that was rugged, user serviceable and had a depth of discharge that a LiFePO4 battery offers vs a standard 12VDC AGM battery. Our previous 12VDC/100A AGM battery weighed 64 pounds vs 28 pounds for the SOK battery. The SOK is encased in a steel enclosure with a built-in BMS (battery management system) and has 4 replaceable cells inside. I can’t repair a faulty AGM battery.

I chose a Milwaukee Packout Toolbox to house the battery. Below the lid is an XT60 connector so the battery can be charged via solar panels.
I added a BlueSea fuse and a Victron 75/15A MPPT solar charge controller.
This was a smaller Milwaukee Packout Toolbox I used to build a “Breakout Box” for multiple charging options.
I added a dual USB 3.0 port, a switch, another dual USB 2.0 port and a 12VDC cigarette lighter port. When driving the car, I can charge the battery via the cigarette lighter port if needed.
On the other side I added Anderson Power Pole connectors and another XT60 port for various charging options.
Inside the Breakout Box I added a BlueSea Fuse Panel to keep things neat and organized. Each port goes to a separate fuse block. It also holds various charging cables and a Voltaic Sytems USB Touchlight.
Complete unit.
The battery and breakout box are connected via an XT90 connector.

The main benefit for us was a modular approach, lightweight, user serviceable, 80-90% depth of discharge and a rugged build. Not to mention this battery has a 7 year warranty and 4000-8000 charge cycles! 12VDC AGM batteries are heavy and the depth of discharge is commonly quoted at 50% but reading the manufacturers engineering specifications, you will note that a lot of them say that 50% depth of discharge is 12.2 volts.

I am also an amateur radio operator and like to operate in parks and such so I needed the added capability of a bigger battery.

On this trip we brought a laptop to edit photos and videos, the navigation tablet, 2 cell phones and 2 GoPro’s as well as various other USB powered items. I do not like using the main vehicle starting battery to charge things unless the vehicle is being driven so it made sense to bring a separate battery for our charging needs.

We utilized 2 SunPower 50 watt, thin, flexible solar panels while in camp to keep the battery topped off.
The Victron MPPT charge controller had BlueTooth connectivity so I could easily check the charge status on my phone anytime I wanted.

We had all the power we needed or wanted for the duration of the trip. If we decide to get a 12VDC refrigerator in the future I think this battery can handle it.

The battery and breakout box ride behind the passenger seat while the solar panels ride behind the drivers seat. Just like a canoe or kayak, we try to keep the load balanced in the vehicle.

Well, that’s a snap shot of our Auxiliary Power Supply while camping. Maybe it will give you some ideas! Thanks for reading…

1 Comment

  1. WONDERFUL Post.thanks for share..more wait .. …


Leave a Comment

Fill in your details below or click an icon to log in:

WordPress.com Logo

You are commenting using your WordPress.com account. Log Out /  Change )

Facebook photo

You are commenting using your Facebook account. Log Out /  Change )

Connecting to %s