Portable Off Grid Power for Amateur Field Communications

Hello Operators.
Today's topic is Portable Off Grid Power. I know this video may seem out a sequence, considering so much has already been done on the channel with this topic. With three DIY LiFePO4 builds published, field testing of solar panels, and an extensive amount of other information supporting the off grid ham radio operator, it was time to publish the introduction for the series.
In this video we finally start tying everything together. The interaction between the solar panels, the use of lithium iron phosphate cells, the importance of picking the right charge controller, and how we deploy it all in the field. So, today's video is titled, Portable Off Grid Power for Amateur Field Communications.

Video URL:

Currently there are 3 LiFePO4 builds on the channel.
DIY 5Ah A123 26650 build QRP+
DIY 10Ah Headway build QRP+
DIY 10Ah Headway build QRO+
There are several more incoming, including one QRO LiFePO4 pack, using 18650 cells. You'll find all of those build videos on the series playlist.

It was important to publish the build videos, some deployment videos, do some field testing, and get some experience under my belt before publishing this video. That is why this video is out of sequence.

Be sure to check the video description for all the links, and other supporting information.

73
Julian oh8stn

 

Been following and enjoying these videos.

I don't think it matters what order things are done, they are enjoyable just the same with each new video.

One challenge I have with my own setup which is considerably very much the same as yours is consolidating all my portable equipment into one Pelican carry case.

So far, I am still carrying folding solar panels, feed line and portable antenna equipment separately inside a separate military carry bag, but i'm figuring out ways of getting everything smaller and easier to carry. For example, I figured out a way to get an entire SOTA link dipole packed nicely inside a VCR tape cassette storage case.

This portable "antenna kit" is now placed inside the Pelican case with the rig and other equipment.

Another thing I did was use pvc pipe with capped ends as a convenient way of storing solar panel cables, adapters, power pole extension cords, power pole Y adapters ... and other things made out of "wire" similar to that.

I even thought about constructing a LiFePO4 battery inside a large diameter pvc pipe with caps on both ends. Something to think about if you want extra rugged battery packs.

Some pencil cases are rugged with tough zippers and are great for holding rig user manuals, log books, pens, paper etc. Some of these somewhat oversized pencil cases are even waterproof as an extra bonus.

Keep these great videos coming.

 

Very nice video. I'm glad to see that someone is getting the word out about LiFePO4 batteries. I run a 100 watt rig on them for Field Day.

I've built dozens of LiFePO4 batteries. From 5AH to 100AH batteries.

From the video, it looks like you're using a dual port BMS which has separate charge/load leads.

If that's the case, you probably don't need the solar charge controller. The BMS boards in my batteries do the job of the controller, and cut the charge from the battery when the battery is full.

Try it without any equipment hooked up. If your BMS's work the same as mine, you'll see with a volt meter when the BMS turns off the charge. Might save you some space in the case.

John - kb8uhn

 

Great but cannot import lithium batteries to Hawaii?

 

While it's true you can get away with charging up the battery using the built in battery BMS circuit and without using any charge controller, it needs to be understood an MPPT charge controller does more than the internal BMS does in terms of actually improving solar panel charging efficiency, especially when the solar panel is operating in low light, or less than ideal conditions.

So using a good quality MPPT charge controller can actually maximize solar panel throughput, improving charging efficiency and that extra 10-30% more power it can harvest from the sun is a good reason to use one.

For example:

 

I really appreciate the videos and the details you provide. This year I intend to improve my solar capability - and your information is pivotal.
73, Dan WD4NG

 

Thanks for all the great information keep it coming I work qrp on the lake shores of Lake Michigan very helpful info looking into the products you are using at present time I am using a Deltran battery 12v 26-35 AH 96 Watt Hrs LCA 480 but have no way of charging when in the field no solar charger as of yet for this unit may have to go to what you are using any help would be greatful will keep watching your input Bud W8BUD

 

Very much enjoy your videos. Will be setting up QRP rig and was looking for alternative, dependable power supply for field use. I am anxiously awaiting delivery of a new product called Water Lilly. It produces power from wind or water flow. I really appreciate that you are sharing your knowledge and experience. It is inspiring.

73

 

Wow, such amazing comments, I don't know where to start.
Happy Easter operators. I'll come back to the comments tomorrow.
73
Julian oh8stn

 

Julian I am very interested in your solar panel you have on the top of your car in video can you give me some info on it thanks Bud W8BUD

 

Your videos are very helpful. Than you for posting them. I have built several lifepo4 battery packs with the Headway 10ah batteries but I would like to build one with 2 rows of 4 for 20ah. Do you have a suggestion as to which BMS I would use for this? 73 ~Ron

 

I have thought seriously about adding LiFePO4 batteries to my portable operation. Right now I just have a SLA/AGM battery box that I keep charged with a folding solar panel. Unfortunately, the CC that came with it isn't compatible with lithium batteries. If I built a LFP pack with BMS that would tolerate input from that CC, that would be ideal. Otherwise, I'm looking at replacing the CC with one that'll do both AGM and LFP.

I'm also concerned about putting everything in a box. I am building a 2m/440 go box and I could just throw a Bioenno battery in it, but that limits it's usefulness for other radios. Another option is to have separate power-only box with a good charge controller, and then I could power more radios simultaneously.

I'm open to thoughts on any of this.

(Oh, and I've already watched nearly all of your YouTube videos multiple times, Julian. Good stuff.)

 

I also have a couple of folding solar panels (US military issue) I use with LiFePo4 battery packs inside a Pelican case / transportable station.



The battery is easily removed by releasing a simple velcro strap. Everything requiring power is on Anderson power poles, so this makes it easy to disconnect the battery and reattach it to any other pieces of equipment with Anderson power poles.

You can certainly get away charging the battery using the BMS and without any solar controller whatsoever.

I have done this myself on multiple occasions, however a primary advantage of using a Genasun MPPT controller is not about the idea it's compatible for charging LiFePo4 batteries in itself , but rather it's about the fact an MPPT controller maximizes and squeezes every ounce of solar energy from your solar panel to charge the battery up to 15-20% more efficiently.

So the BMS inside the battery is not going to do that for you, and it might take a little longer to charge a battery, but it will definitely get the job done.

Another thing I like about the Genasun controller is it's one of the very few controllers on the market that's actually FCC certified. It won't make any noise in your radio receiver.

 

While not portable there are a few scrap yard Tesla S battery packs powering homes these days with more to come.

Carl