Portable Ham Radio battery Pack DIY

[@OH8STN]

Parts list with all links is published on my blog: There are 26650 cells, BMS, 26650 cell holders, spot welder, a 3d printed enclosure, and info on the charge controller. 73 Julian oh8stn

[@alaricsnellpym]

What is the clear giant heatshrink stuff you put over the entire pack? I've never managed to find anything like it, which is why MY battery pack is contained within a crinkly mess of tape that I suspect will dissolve if it ever gets rained on... Thanks!

[@OH8STN]

It's a PVC heat shrink film 275mm flat opening. I'll try to find it and add to the parts list.

[@reidlanham2011]

Looks like I'm ordering parts again! I'm still using the 2 battery packs that you showed several years ago. These were the ones using 4 3812S headway batteries. Both are still going strong! Thanks! 73, K8JLW

[@OH8STN]

This is definitely the best comment of the day! My headway packs are also going strong. In fact, this is the reason there hasn't been any Builds on the channel for some time. Anyway, thank you for watching and for the kindness. It's greatly appreciated. 73 Julian oh8stn

[@permaculture3]

Exactly what I was thinking

[@woodgrainandwhimsey]

I’ve been tempted to build one of these packs since I saw your older pack. I discovered something this week and in the typical Julian ‘less is more’ style I felt compelled to share as it might be an alternate solution that meets my needs just as well if not better. It turns out that any quality battery charger pack with a proper Multi-voltage PD USB-C port good for 100 watts for powering notebook computers will power the IC-705 for quite a while and all it needs is a $10 cable from Amazon with a 12v output. I found one easily enough which already had the right plug to insert directly into the IC-705. Cheap. Easy. Compact. No soldering. No welding. The only gotacha right now is solar options aren’t as powerful as using a Genasun and a larger, higher voltage, solar panel. Finding a practical combo of USB solar panel and battery is my next challenge. See if I can’t find a combo that makes the kit sustainable for use over many days. I plan to pick up a second battery with a 20V cable for extending the battery on my POTA computer and do some testing to see how many days I can run without charging.

[@woodgrainandwhimsey]

I should add that 100w is overkill. The 12v spec on USB-C provides 3 amps.

[@andrewrobb633]

Hi Julian, I have watched this video a few times and read your blog post which was fortunate as I just bought a new to me IC703 to get me on HF for SOTA and now I need to build some batteries. Thank you for taking the time appreciate it. 73 Andrew VK2ZRK

[@OH8STN]

You're very welcome Andrew. 73 Julian oh8stn

[@thuff3207]

This is a good idea and I need a battery spot welder! Thank you for sharing! It does encourage us to get building.

[@OH8STN]

Very happy to read this comment. The more we build, the more we understand our own gear. I can't build an all mode all band radio, but a power supply is reasonable. 73 Julian oh8stn

[@KevinW8BRY]

Thanks Julian for this video. I genuinely mean this. Your channel provides great benefit to the community.

[@edframbes5296]

Thank you, Julian! You're the master of information! 73 de K8EAF

[@richardwhitcroftkc3rrw63]

great video.... always something to learn. My thought on building whatever you need.... if you build it you can fix it if or when it breaks. Thanks and 73

[@Auxrad39]

Thank you for showing us the usage of smaller battery packs for short field runs (pota and sota) keep it up 73

[@OH8STN]

You are very welcome. With these new energy-efficient radios we have coming out, the small battery packs are more practical now. Thanks for the kindness stand for watching. Much appreciated. 73 Julian oh8stn

[@nvrumi]

Julian, these videos are simply inspiring. Although I have several Bioenno packs, I would really like to build my own with an integrated charge controller. The A123 cells are a great size and larger packs can be built on the headway cells. Great material... thanks!

[@permaculture3]

Now I know what I’ll be building this winter…Great series Julian. Keep up the great innovative design and construction.

[@OH8STN]

You're too kind 🙏 73 Julian oh8stn

[@KevinMaxson]

Well done. I’m more likely to build this than your other monster batteries.

[@エルネストムーアガルシア]

Outstanding, Julian; many thanks for this series. In addition to doing as you have done here for a 4S build, size considerations apart, there should be no reason why a KX-2 owner can't follow the same process to make a 3-cell battery that fits inside the radio (like the current Elecraft lithium-ion battery). There is a lot to explore here. 73

[@OH8STN]

Completely agree! The charge controller would still need to be outside the radio but that's an improvement for sure. I really wish I could craft would upgrade that charging circuit. Thanks for the comment and for watching. Much appreciated. 73 Julian oh8stn

[@sspence65]

3S would only give you 9.75 volts. The KX-2 has a 11v internal battery.

[@OH8STN]

I think he meant 3s diy lithium ion.

[@marcusjenkins]

This is basically what I have to give a boost for my IC705. It works perfectly, just the right size for my Decathlon soft lunchbox that holds the radio, cables, EFHW antenna, battery, logbook and even a multi tool and a Mini 60 analyser. 73 Marcus EA5HQ

[@OH8STN]

Agreed. Kind of amazing Icom didn't do a battery like this themselves. It's only slightly bigger than the internal battery on the 705, but double the capacity and of course much more current capable. 73

[@brandonharden1165]

Nice work brother! Also loved your article on the power grid! Semper Paratus!

[@janhenkins]

Thanks Julian, excellent stuff! You're inspiring me to get my backside in gear to make myself a proper battery for my X6100/FT817nd! Currently I'm lugging around a much bigger 6.4Ah LiFePO4 battery, which is overkill for my usage.

[@davem0udb]

Really enjoy these videos

[@OH8STN]

Thank you 🙏 73 Julian oh8stn

[@PatrickKQ4HBD]

16:34 Strain relief for the power cord? Just a big glob of hot glue is better than nothing. I can guarantee you that I would yank mine out eventually. With your interest in anywhere-anytime-any-conditions operation and that lovely view of the water, have you ever taken your kit out ON the water for greater mobility? Seems like a sailboat would be a good fit for what you're doing. Even comes with a mast! 😀

[@OH8STN]

Thanks for the strain relief tip. I'll add it tomorrow. I have been out on the water with a canoe and traditional row boat. Seriously thinking about an small rigid inflatable to explore the islands on the coast. Before that, a snowmobile for winter ops. Awesome advice and kindness. Thanks for watching and much appreciated. 73 Julian oh8stn

[@wjf213]

I really enjoy watching battery builds like this. Small compact but powerful enough to do the job, AND solar rechargeable. I hope you do a follow up video on charging this with solar. Do you think this would work with a Midland GMRS 15 watt radio just for daily use hiking around the ranch, or do you think it wouldn't be enough power? Thanks and keep up the great work.

[@OH8STN]

More than enough. I tested with an HF radio and small amplifier.

[@johnslaymaker]

Excellent vid, love the highly detailed, methodical style. Looking forward to the parts list. Cheers~

[@OH8STN]

Thanks John and you are very welcome. I just hope it's the part list on my blog, the link is in the description. KZbin is kind of funny about external links so I did it this way this time. Thanks for watching and for the reminder. 73 Julian oh8stn

[@L1mechanicstc]

Another great video. Super helpful. I picked up a spot welder, now I'm looking for a build. This helps. I'm thinking of building something for my G90. 73

[@OH8STN]

G90 🤔 I also tested the G90 but forgot to include the pic in the video doh! 73 Julian oh8stn

[@PatrickKQ4HBD]

Do you like your spot welder? Looking for recommendations.

[@OH8STN]

It works well enough. Would love a more powerful model.

[@roscoe1052]

Julian, do you links to sites selling similar batteries in europe? I'm not quite sure what the specs of these batteries should be. Thanks for the great videos.

[@stahpit1971]

Thanks for the video!

[@OH8STN]

You are very welcome.

[@Mottersmotters]

Fantastic video Julian. Great watch. I am yet to get into HF. I am thinking of the 817nd second hand and one of these batteries would be fantastic. Motters M7TRS 🇬🇧 73 👍🏻

[@DalenKruse]

I love your solar power and battery pack videos, Julian. Very helpful information. I have two questions I hope you can answer: 1. When using a charge controller without a load port (like the Genasun GV-10), can you have the battery connected to the radio (discharging) and to the charge controller (charging) at the same time? 2. Your blog has mentioned using a high-quality BMS for the battery pack builds. What are the things one should look for when selecting a quality BMS? Thanks again for the great content!

[@OH8STN]

Q1 Absolutely! Connect the controllers battery port and the load in parallel. Q2 BMS specs depend on your chosen battery chemistry. I always try to find BMS board with balancing, shut circuit protection, low voltage cutoff, over voltage protection, and solder pads which are actually big enough to carry the current you're trying to get out of your pack. Hope this helps 73 Julian oh8stn

[@dougdaniels]

Great instructional build as always. If you were to recommend a spot welder other than a "cheap Chinese" one, what would it be?

[@OH8STN]

Thanks for the feedback Doug. There were a couple of DIY kits from Germany on KZbin couple of years ago. I haven't started researching yet, but I'm hoping one of those still available.

[@christophercobb4317]

Thinks I been watching you for 3years this is one of the best if you have time to tell what kind of charger you use for this pack

[@christophercobb4317]

Please share

[@OH8STN]

Did you check the link in the description? oh8stn.org/blog/2022/07/18/diy-lifepo4-battery-pocket-portable/

[@jameshall5835]

Julian, if I may ask, what heat shrink tubing are you using for your battery packs ? I’m building the 10Ah QRO pack with the Headway cells and have found that the thin stuff sold at Amazon is total crap. The heat shrink used specifically for battery packs looks to be too thick. Trying to get a gauge on measurements as well - most have a length of 12” - seems too long. Thanks de WB4YDL Jamie

[@OH8STN]

Yes agreed. I have not had much luck with Amazon heat shrink. The one I use is called PVC heatshrink, 250mm-350mm wide. It comes in various thinknesses but it hard to find. It almost always come from China via eBay. There is no consistant listing, so you'll just have to search. Makes you miss the old days of quality electronics shops one could walk in to. 73 Julian oh8stn

[@garroyo7533]

Is it possible to build something like this for a hand held radio ? That i could carry on my waistline. I work in a steel mill and we must have radio on us at all times. My battery will last half a shift before i have to replace it. Could this be possible? Thank you

[@OH8STN]

Sure! Same battery as here, we just add a voltage regulator and connector to plug in yo your work radio. Keep in mind though, your work radio battery is probably damaged if it only lasts a few hours. I'd try replacing it first.

[@jjamison3859]

With the Peovi Full wrap and front cover Will it still fit in the maxpedition 12-inch x 5-inch bottle holder ?

[@OH8STN]

It does, it is a tight fit but Perfect fit. There is also a microphone, packtenna EFHW or CHA EF40 and the battery pack. I'll post pics to instagram and the community tag shortly. Great question! 73 Julian oh8stn

[@jjamison3859]

@@OH8STN thanks J KE8AKU

[@tombaffa9374]

Great build! Thanks

[@OH8STN]

Thanks for watching Tom, much appreciated. 73 Julian oh8stn

[@tombaffa9374]

@@OH8STN always useful info. 73s W0GEO/4

[@cyrilb7011]

Hi Julian, Hi to the community ! My Xiegu G90 manual specifies a 13.8V minimum voltage input to guarantee the performances. Here I see 13.4V "only" ;) . What would be the solution to operate with a voltage range from 13.8 to 16.5 V, as the G90 requires it? Maybe having 5 cells in serie, but do such BMS exists ? What about a 8-40V to 13.8V DC-DC regulator with 14.8V tor24V battery ? Thanks for your suggestions !

[@OH8STN]

The g90 doesn't require 13.8 volts it's a wishful number. Here's an example, you're sitting in your car with the motor off, your g90 is operating off of the automobiles battery. What's the voltage of the battery when the alternator isn't spinning? My g90 operates anywhere between 11 volts and 16 volts without any issue at all. The only reason the battery pack says 13.4 volts, is because it isn't charged to full capacity. Hope this helps. 73 Julian oh8stn

[@cyrilb7011]

@@OH8STN Thank you for your message Julian, If you have the opportunity, I'd be glad to know the voltage ramp through the discharge. Your videos are top quality, you helped me so much time to choose and tune my portable setups, many thanks !

[@OH8STN]

Lithium iron phosphate packs have a flat or rather hockey stick style of discharge curve. There is a sudden drop from 14.x to 13.6 to 13.8, then it stays relatively flat for 90% of it's discharged. After 90% of drops pretty rapidly. Let's Google be your friend. This is a well-explored topic about lithium iron phosphate batteries. Just search lithium iron phosphate discharge curve.

[@taldeus4008]

Am I missing the parts list?

[@OH8STN]

Thx, couple of hours

[@ericescobar4588]

Any all in one solutions you'd recommend before you next next video comes out? I missed out on the lightsaver max and it's been out of stock for quite a while

[@OH8STN]

I really needed dto think about the right answer to this question. There is the BAT500 soon to be released from DIY599. @Powerfilmsolar is also working on a new version of the LSM. It should hopefully be released later this year. The reason I am building is there is nothing I could recommend which is right here, right now. 73 Julian oh8stn

[@jimw7ry]

Very cool! But... All the links for parts on your blog are busted... Thanks, 73 Jim W7RY

[@OH8STN]

They were good when the video is published. Sadly, every time I do a video like this, parts go out of stock. I can't keep up with chasing links, So you'll have to do some research.

[@TheDaveho]

Hi Julian, do you have a video of adding the GV-5-MOD? Thanks 73 Dave - N1DCH

[@OH8STN]

I'll add one if you think it's useful. There's only a few connections. Very often people want to connect it up in different ways. I can do a short video on how I did it.

[@TheDaveho]

@@OH8STN thanks I’m interested in how you did it. From looking at the board it seems like there could be options. 73

[@OH8STN]

Yes, I'll get it done. What I actually did was remove the connector block, took the pins off, and soldered my wires directly to the solder pads. This made the charge controller practically flat. No ribbon connector to get in the way. You have to have a steady hand and with my eyes magnifying glass. Needless to say it worked extremely well.

[@chrissewell1608]

Julian, where can we find your blog at? So we can refer to the parts list on this build, and other fun info. Thanks, Chris - KE4WRN

[@OH8STN]

Direct link In the description oh8stn.org for main site

[@elanpaim33]

hi great info tnx btw what bike do you have there please MANY THANKS VY 73 ELAN

[@OH8STN]

Thanks :-) here's a post about the bike from my blog. oh8stn.org/blog/2022/06/17/fat-bike-portable-ops/ 73 Julian oh8stn

[@keithfrost1268]

Love the content. I just got thru getting a small battery for a little DMR radio I was going to keep in my pack when riding dirt trails. I noticed a lot of Lipo batteries for RC cars come up in my searches. they are kind of pricey, but seem to pack a lot of charge in a small package. would they be usable? can they be charged off a solar panel?

[@OH8STN]

Many RC batteries are LiPo which have higher energy density but are volatile is misused. They also lack the internal battery management board to balance to indivudual cells making up the pack. If you use them in the field, then balance charge then at home, they can be a nice option. I don't use them as I like to combine my batteries wth a solar charge controller and solar panel for extended field comms. No reason why you couldn't use them. 73 Julian oh8stn

[@ericescobar4588]

Love the video! Can’t wait to see the charge controller

[@OH8STN]

Thanks Coming soon! There are a couple of different options. The GV5MOD LFP is a tiny board, RF quiet, and practically flat. There are other boards which are larger but not so "pocket portable". 73 Julian oh8stn

[@OH8STN]

Take a look at this blog post: oh8stn.org/blog/2022/07/18/diy-lifepo4-battery-pocket-portable/

[@jakep5121]

Love it 😀

[@on2vhf83]

Hi Julian, the pack is finish 😂, but no sun for charge via my pannel lol 😅, please info for charger model for charge into my home, 73 de laurent on2vhf

[@OH8STN]

Well done! 💪👍 I use a 16-19 volt laptop charger with no more than 3 amps charging. This charger goes into the solar charge controller solar panel input. 73 Julian oh8stn

[@on2vhf83]

Hi Julian, the BMS is burning lol 😢, i am user power supply for laptop, 19v and 3.42 amp, is too high power, please support, 73 de laurent

[@manofthecroc]

Excellent video as always!

[@OH8STN]

🙏👍 73 Julian oh8stn

[@Stevenfclark]

Julian, you may have already shared this however where are you purchasing your cells and other components? 73 de N1AD

[@OH8STN]

Battery hookup oh8stn.net/batteryhookup

[@OH8STN]

Use my callsign for a discount 👍

[@TheNoCodeTech]

Fantastic!

[@OH8STN]

Thanks. Baby steps but we know what we're doing now :D 73 Julian oh8stn

[@mattghoward]

Nice video Julian - I now have a range of packs to suit a range of deployments from 10Ah up to 100Ah - next on the list is something like this :-) - It might be useful at some stage to explain the function of the "balance" BMS

[@thed8229]

Heck yeah! More of this please. I am very diy batt pack curious, this helps a lot. K0ATV

[@OH8STN]

More incoming. I am quietly working on the battery and solar power series. 73 Julian oh8stn

[@t.m2933]

Outstanding as always! Thank you for sharing with us... KN6PWH...73

[@OH8STN]

Thanks for watching and for the kindness. Much appreciated! 73 Julian oh8stn

[@amham48]

i don't think the plastic separators will contribute much in the way of cooling given that you are wrapping the entire battery in shrink wrap plastic. No air circulation there...however they do make for a neat build. Of course the Anderson Powerpole (I won't digress into how awful they truly are) connection is also the charge/discharge port.

[@OH8STN]

In this case they really act to separate the cells, preventing any hot spots between them. As for the connectors, I generally prefer XT60, but for interoperability with other group members, the powerpoles are fine.

[@mikemiles3068]

Good video Julian 👍73 KV5P

[@OH8STN]

Thanks Mike. 73 Julian oh8stn

[@Gordonseries385]

👍

[@OH8STN]

Thanks /3 Julian oh8stn

[@edwatters6377]

Nice job..... KC2ORP

[@petemillis4666]

Excellent content Julian. 73 de M3KXZ

[@OH8STN]

Thank you Pete much appreciated. 73 Julian oh8stn

[@gsummers1150]

⭐ p̾r̾o̾m̾o̾s̾m̾

[@longrider42]

Its Bio-Enno, not what you said. Okay, so maybe english is your second language? Any ways, as a legally blind Ham Radio operator, I find stuff like this interesting to watch/listen too. But due to my bad vision, and lack of funds, I would never be able to make something like that.

[@OH8STN]

I speak two languages reasonably well and a third poorly. Some words are spelled the same in various languages, while pronounced differently. Deal with it! Previously you mentioned riding a bike and buying a commercial battery. A pre-built battery is probably the best option for someone who has no vision. However, this is a very simple build. If you can ride a bike, you can definitely build this battery. 73 Julian oh8stn

[@bigphil6980]

hi Julian is this pack big enough to run my Xiego G90 for a POTA day or would i need to build your larger Battery's 73 Phil 2E0FJQ

[@OH8STN]

I Phil. It'll definitely run the G90. For how long is a great question. Depending on duty cycle, I imagine you could get at least six hours out of this pact with the g90. That's especially true if you have a solar panel connected as well.

[@metroatlantahamradio334]

Devil Dog Shock Troop!! Let's go with it!! 73 DE K4KHO

[@OH8STN]

👍🙏 Semper Fi

[@on2vhf83]

Exellent, Nice video, 73 de laurent on2vhf

[@on2vhf83]

hello, what charger do you use? with 100w solar panels? thank you, 73 from laurent on2vhf

[@on2vhf83]

Hi, i am buy all item for build this nice pack battery for portable activity, 73 de laurent on2vhf

[@OH8STN]

Genasun GV10L or Victron 75/15 73 Julian oh8stn

[@on2vhf83]

hello, to charge the batteries at my home? which charger to use, thank you, 73 from laurent on2vhf

[@on2vhf83]

@@OH8STN hi Julian, charge controller mppt 75 | 15 , is ok for charge other battery ??? 73 de laurent on2vhf