KX2 battery replacement

Saw this on ebay earlier. Curious if anyone has tried one yet? Says rated at 3400mAh. Looks like it will fit in the KX2 as well ?? Should be able to charge with the Elecraft charger.



Todd KH2TJ

image Hey Todd,

Yes, it will fit in the KX2 and you can charge it with the Elecraft charger.

I bought a similar pack from eBay for $15. It’s designed to be a battery for some BIONET medical device. It’s rated 2600mAh, and has been good. I charge it with a LiPo battery charger - it gets charged up to 12.6V. I can get 2 activations out of it before the KX2 kicks down to 5 watts, and it will keep going at 5 watts for a few hours. I’ve had it for 2 years, and it has lost maybe 10% of it’s capacity after MANY cycles.



I built my own KX2 replacement battery using Panasonic 3400mH 18650’s and BMS board. The BMS board is abut $1.50 from China and the cells are usually $20-$25 for 4 of them. You can build one yourself for $30 or less. They are great cells and last a long time in the KX2. Thats what I use for SOTA.
Tim - K5DEZ

Hey Tim - I built one too! I used some Samsung cells that I harvested from an old laptop battery. Works fine, but for $15 shipped to my door I couldn’t resist the ‘Bionet’ battery. It’s been a great battery. No idea what the cells are in there, but they have held up well. All I had to do was cut the weird connector off and put the right one on.


So a quick look on the various webpages (epay, alibaba, amazon etc etc) I came up with the cheapest being $10.99 plus shipping for 2200mah, from China. Couldn’t find the bionet battery, but do recall seeing that one several years back. In fact, think I first saw it on AE5X’s blog on aftermarket KX2 batteries. Most of the links on he provided are no longer good. I could buy the parts/pieces to build my own, which will be a fun project, and bring the cost for a 3400mah battery at just around $35, maybe a bit less. All depends on shipping/Kalifornia taxes :wink:

For the time being, I pulled the trigger on the one I first ref’d. Came out at $29.99 + Gavin’s share of $3.22, but free shipping…

Should be here Thursday afternoon. Let you know how it works out…

Thanks for the info/replies…

73, Todd KH2TJ

Hey Josh. It was a fun, easy project…twice. The first time I put it together with wires, solder and electrical tape to hold it together. Then after I finally bought a battery welder from the auction site I took it apart and re-did it with welded solder tabs and heat shrink tubing. Although the first one fit fine in the KX2 the second version fit much better. Plus now with the welder it is a “piece of cake” to make battery packs now.
Tim - K5DEZ
P.S. and Tnx for the recent chases

That battery pack looks like the one in my HB-1B cw only rig it works fine I have a couple packs of them. The Wall Wart charger is a filthy thing it causes lots of shack qrm while charging them up.
Ian vk5cz …