Baofeng Battery upgrade to 18650 Lithium-ion cells

July 29th, 2018 No comments

It has been more than a month since I had checked in to my club net (http://www.gmarc.org/). So far I have had two Baofeng (UV-5R) and it lasted years! Eventually the speaker and microphone started giving up along with the battery going bad. One of my repeater friend gifted me with a nice Baofeng UV-82HP to keep on the air. Then I got busy with school and then the battery gave up. Unlike UV-5R model, the battery for UV-82HP is very different in its form factor. I thought of ordering a new battery, but then decided to upgrade the existing battery with what I can find from my scavenge bin. My goals were very simple

Goals

  • Changes Should still allow me to swap to a new Baofeng battery
  • Should be able to use the existing Baofeng charger

I knew I will be giving up the pretty look and it will have a dangling appendage. The best choice will be to use a 3D printer and do it the right way.

      Dismantling the UV-82HP battery

    The battery is labeled as a Li-ion 7.4V 1800mAh/13.3Wh battery. And the battery model UV-5XTP.

      Battery and Unity
        Opening the battery was pretty easy. Used a screwdriver along the notches at sides and pry it open. Luckily the pieces were not glued tight. Once got the edge of the screwdriver in, the unit just opened itself
        BaofengBatteryOpen

        The configuration is  a 2S (2 cell’s in series). The battery had a protection board. When I was opening the unit, I never thought of scavenging anything other than the battery shell. If the battery protection unit is functional, then no harm in reusing it.

        Breakdown

            The Upgrade

          I had the wires all cut of and scavenged the battery protection board. For the new cell, I looked into using a 7.4V 1000mAh battery that I had laying around. The 1000mAh rating will be a downgrade to what the previous capacity was.

          The next option was to use a 2 cell 18650 Li-ion holder and use it to power the unit. I can see the advantages this way. I can use my stand alone 18650 chargers and if pack it properly, I should be able to use the Baofeng’s stock charger.
          Before packing
          BeforePacking-noninsulation
          PackedAll

            Testing

            Now to test the hack job. The dangling appendage (the battery holder) may be better. At this point, I can use more 2S in parallel to get more talk time out of it. Before testing, I got to charge my cells. Could have used the Baofeng stock charger, but if I needed something to charge it quickly. I let Babushka take care of charging while I was dremeling and other things.

              Charging Battery
              And!…. now, it works!
              Working
              I haven’t tested how long it runs, but these cells carry more power than the stock batteries. Also, I have quite a lot of 18650 cells scavenged over the years. I can move on to make a new battery pack and make it last longer. But for now, this will help me get on the GMARC net for a start.