Batteries for Portable and Field Radio

 Batteries for Portable and Field Radio

When we go portable or operating in the field with radios, what batteries do we use? Well if it is a handheld radio or the radio comes with its own battery installed chances are that is the battery you will be using in the first instance. If you intend operating for any length of time or are preparing for an emergency situation chances are you will have auxiliary or backup battery or power supply.

Myself, when in the field or up in the hills and mountains I currently work exclusively of battery, though I will be adding some solar panels to that mix shortly. But lets concentrate on batteries at this time. New Zealand being the antipodes of just about anywhere suffers a lack of range and choice that our fellow radio operators in USA, Europe and even Australia can often take for granted. With batteries specifically, it comes down to the regulations regarding shipping of some of the new technology lithium ion and phosphate batteries, which are light weight and have greater endurance, that we are missing out on. So, we have to make do with what we can get our hands on. I have seen field operators using battery packs for cordless tools or radio controlled cars. But in most instances these need some circuitry to step down voltages and stop overloading the radio equipment. Personally I have stuck to the more traditional batteries. The picture above shows the batteries that I have, and use, or hope to use most commonly when out with a radio. Listing them from top left they are……

DiaMec 12.0V/9Ahr Gel/Lead Acid 2490 gr 87.8 oz

PowerTech 12.8V/12Ahr Lithium 1415 gr 49.9 oz

DC1298A 12.6V/9.8Ahr Polymer Lithium Ion 250 gr 8.8 oz

Kaiser Baas 5-12V/10Ahr Lithium Polymer 317 gr 11.1 oz

Powertech  5-20V/20Ahr Lithium Polymer 413 gr 14.5 oz

Powertech 5-20V/20Ahr Lithium Polymer 493 gr 17.3 oz

Promate 5-20V/20Ahr Lithium Ion 713 gr 25.1 oz

And then there is one more battery, or possibly more appropriate, power source that I use from time to time in the field.

It is a car jump starter. I can tell you little about it other than it is a Mechpro that I bought for $120 about 8 to 10 years ago, and for powering the Yaesu FT-891 radio that draws a current of 9 Amps….it just works. I power it off the 12 volt lighter socket. You can still purchase these jump starters in New Zealand but only of a bigger size. Their specs are - 12V 1800 Amp Jump starter 40 Ah Sealed AGM Battery. If your mobile operations revolve around a vehicle this can be a very viable option. I have no idea how long it could power the FT-891 as I have never done any tests on it, though I have used it in an activation for a total of 2 hours operating at 80 watts. One other aspect I like of it is that it is built to be permanently plugged in on charge so it is always ready for use. Very good in an emergency or even when you just lose power. It can also be used to charge handheld radios, cell phones and tablets. It is a useful item to have when the grid is not available.

However, over 90% of my excursions into the field to operate radio are without the backup of a vehicle so anything that I take with me has to be capable of being carried in a pack, so weight and size are everything.

When I started taking the Xeigu G90 into the field I needed a small battery that could provide at least 5 amps. There was not much of a choice of LifePo4 batteries in NZ or at least not at a price I was able to afford so the sealed gel batteries were the only choice. The DiaMec served the purpose but weighing in at 2.4 Kg it is a little ’Pig’ to be carrying up hills, plus I could only guarantee 2 hours output from it before it was flat. I know that the battery is rated at 9 Amp hours so either I was heavy on the transmit cycle or the  specs were optimistic. 

Then with the advent of a Xiegu x6100 and an Icom 705 into my collection, LifePo4 batteries became more plentiful and at a price I could now afford. While both radios have an internal battery, which I have used in my operations, they are restricted to 5 watt output and X6100 realistically only gives over an hour's use and I have used the IC-705 out to nearly 2 hours but reports suggest that 3 hours isn’t unrealistic. I might have to put that to the test one day.

The PowerTech LifePo4 battery pictured above, while is a little larger than the previous sealed gel battery it is over a kilogram lighter and was rated at 12 Ahrs. Both of these radios only draw a maximum of 3 Amps and while I have only used this battery for a continual total of 4 hours before charging I feel that they could quite possibly go out to near 6 hours.

Just an aside here. The first LifePo4 battery that I purchased and tried was a smaller 7 Ahr Powertech. It was smaller than the 12 Ahr and literally weighed half the weight again at only 770 gr. It kept going flat on me and refusing to charge. The suppliers were very good to me and replaced it for another but the same thing happened to that one as well. The only conclusion that we collectively came to was that either I was using it in too harsh conditions for it - it was being operated sitting in snow and ice - or they had a batch with a faulty Battery Management System. Whichever, again the suppliers were good in giving me a good price on the 12 Ahr version and I have had no problems since. 

Now a little diversion here. The odd battery out. Now I have to confess here, I have not actually used this battery as yet. 

This battery was on Aliexpress for some ridiculous price of $17 NZD. It is supposedly 12V 9.8 Ahr and comes with its own charger. I have actually charged it and measured the voltage and it gives 12.8 V. I need to get a different connector to use it on my radios and in the interim, moving QTH I have misplaced the charger. So this is going to be a project in progress. If indeed it does deliver what it promises it will be one of my goto batteries only weighing in at 250 gr or 8.8 oz. I will do a follow up post when I find the charger and get another connector fitted.

Next up, my move into Cell Phone Power Banks. I happened to see a video by Steve, KM9G, on his Youtube channel demonstrating the use of a cell phone power bank and Power Delivery cable to deliver 12V 3 Amps to his IC-705.

Now until I saw this video I didn’t know what a power delivery cable was. My basic understanding of it is that cell phone power banks are often capable of delivering a higher rated charge than the nominal 5 volts delivered to the usb outlets. All you need is a cable specifically wired to request the higher power to deliver it to your device. At the time that I discovered this though, it still wasn’t that easy, in New Zealand at least. Do you think that I could find a power bank that was capable of delivering 12V/3A. I couldn't find one anywhere in NZ and there is a restriction on outlets like Amazon shipping them here. In the meantime I found that I actually had a power bank I had bought some 6 years earlier that could deliver 12V1.5A. So I thought I could at least try that at least and as luck would have it I found a power delivery cable on Amazon that would connect to my uSDX+ so I ordered it.

It works a treat and makes a brilliant combination with a mini tuned EFHW to just chuck in a bag when you are flying off somewhere and want to try a bit of radio.

Some months later power banks with the capacity to deliver 3 Amps at 12 Volts started appearing on the New Zealand market. I was quick to take advantage of this and now I have three power banks and a PD cable from the link to Amazon from KM9G’s video that I use to power my X6100 and IC-705 in the field.  I now have a power banks that can deliver 5V/3A, 9V/3A, 12/3A, 15V/3A, and 20V/5A if you only have the correct cable connected between the power bank and the device. 

From right to left, Promate Power Mine which delivers a whopping 38000 mAhr and two Powertech delivering 20000 mAh. Between them I believe that I could keep either my X6100 or the IC-705 powered up for the best part of 24 hours. I have to admit, since putting the power banks into service I haven’t used the LifePo4 batteries and will be recycling them into a field solar panel project that I have on the boil.

The other advantage of the power banks, more so the Promate that can deliver up to 20V/5Ah is that it can be used to charge tablets, computers and handheld radios, and of course cell phones, as well as powering your QRP rig. What’s not to like? They bring with them some real versatility and can be recharged from a socket outlet or from a solar panel….but more on that at a later time.

Here is the Promate charging my Uniden handheld, which requires 12 volts. Incidentally, the Uniden can be left on while charging, but that is another post altogether. But with the PD cables I can charge all of my handhelds, Yaesu, Baofeng, TYT, and GME’s in the field or in any grid down scenario. They really make powering QRP rigs and radio appliances just so easy and I can fully recommend them.

Anyway, that is my journey on powering radios in the field. The next chapter will be solar power in the field. What is your journey so far? We would all love to hear it.

Cheers

Phil ZL3CCI