We have been having some power outages in our neighborhood recently so my plans for a portable power station have been moved up. I have done a lot of research and decided to spend the money now instead of spending more time trying to find something cheaper.
The battery I have chosen is a Bioenno Power Lithium Iron Phosphate 12V, 40Ah LFP Battery (PVC, BLF-1240A) and here is why:
- 12V: All of my ham gear runs off of 12 volts and there are many other available tools that will also run off of the 12 volts. Using a 24V battery is tempting but requires more electronics to get the voltages I am looking for.
- Charge Current: 6A, this is easily supplied by an external power source or by solar panel(s)
- Max Discharge: 40A, my radios need around 21 amps to function well
- Lithium Iron Phosphate (LiFePO4): Lead Acid sealed, gel, or old-school are heavier than I want to deal with and do not provide a weight to power ratio that is appealing to me. There are also a lot of other things that make LiFePO4
- 40Ah: I want to be able to keep a radio running along with phones and tablets for a full day… but I also have to keep a budget in mind so 40Ah is what I bought. A 100Ah battery would be a lot better but is out of my price range.
A negative of the Bioenno batteries is that they are not to be used in series or parallel as they each contain their own Battery Management System (BMS) which is not designed to be used in a multi-battery configuration. The BMS in Bioenno batteries is very highly thought of and works remarkably well.
I chose the Powerwerx MEGAbox because I wanted one box that can hold the battery, charger, extra cables, and more. I also wanted USB-C and a light built into the box, when I looked at small and simpler boxes then included the cost of adding USB-C and a light it was almost as much as the MEGAbox. The light is kind of annoying with its seemingly endless number of modes, but it is a good light and is easily replaced if it gets too annoying.
I am able to fit everything into the box and didn’t have to add any holes or make any major modifications to it. More details below.
I needed a way to charge the batter via external power and solar, preferably with MPTT. Based on reviews and information from podcasts and such I chose the West Mountain Radio Epic PWRgate. The Epic PWRgate is rated up to 40 amps, instantly switch from external power to battery power, will charge Lead Acid, Lithium Ion, and LiFePO4 batteries, has advanced features available when plugged in to a computer via USB, has an optional temperature probe, and comes in a metal case that is very easy to mount.
To measure the power coming from and into the battery I chose the West Mountain Radio PWRcheck+ for its easy-to-read screen and ability to store a lot of data that can be read back later on a computer. The PWRcheck+ is totally unnecessary, but I wanted a way to track the performance of the battery and figured it would be a good way to troubleshoot any issues that may come up.
For use with the solar panel, I got a Powerwerx Watt Meter – DC Inline Power Analyzer to have an easy way to see how much power is coming through the panel. It doesn’t have the features of the PWRcheck+ but it doesn’t cost as much either.
For solar I got the Bioenno Power 100 Watt Foldable Solar Panel (BSP-100-LITE). Its too big to take hiking but is a great size to carry in the back of the car and use for a field-day or to charge the battery on a sunny day when the power is out. I wanted enough wattage to give a decent amount of power to a battery but still be foldable and easy enough to move around. For the price I could have gotten 2 aluminum framed panels with twice the wattage, but they would not have been very portable. At some point I will probably buy those panels, but for now the foldable panel will do.
My mains power supply is a SamlexPower SEC-1235M with the Fan and Powerpole mods documented by Phil Salas – AD5X. I have also upped the voltage it outputs to 14.6 volts which the Bioenno battery prefers.
Modifications to the Box
I removed the top PowerPole connecter on the MEGAbox, took the connectors out and replaced them with Yellow and Gray connectors, Yellow for Solar input and Gray for power supply input, and they run to the Epic PWRgate which also has the battery and “load” plugged into it. I use Velcro to hold the battery in place along with the PWRgate and PWRcheck+. That keeps the outside of the box clean and offers a decent amount of water resistance.
Day-to-day the box sits under the ham shack desk plugged into the SamlexPower power supply keeping the battery topped off. About once I week I leave the power supply turned off and run on battery power until it gets down to around 11 volts, at that point I turn the power supply back on. It works great. I take it outside every now and then to plug in the solar panel to get used to using that setup and learn how it works in the field. The solar panel is ok, but not amazing.
I am very happy with my Battery Box solution; it has already been tested in an outage where it kept my son’s tablet charged until the power came back on. I look forward to using it in an upcoming field day to really test it.