The Smell of Molten Projects in the Morning

Ed Nisley's Blog: Shop notes, electronics, firmware, machinery, 3D printing, laser cuttery, and curiosities. Contents: 100% human thinking, 0% AI slop.

Wouxun KG-UV3D Batteries: Age and Cycle Effects

The first Wouxun (evidently pronounced “ocean”) KG-UV3D HT spent a month or two in my bike, lashed to a kludged version of the APRS+voice interface box and powered by its own lithium-ion pack. After I got the circuit worked out and built a duplicate, I picked up a second HT for Mary’s bike; as a result, that battery pack never got much use.

A pair of discharge tests shows the difference:

Wouxun 7.4 V Packs
Wouxun 7.4 V Packs

The 2011-03 battery has almost exactly the rated 1.7 A·h capacity, at least if you’re willing to run it down to 6 V, and the 2012-06 pack delivers 1.9 A·h. Electronic gadgets measure state-of-charge using the battery voltage, so the older pack “looks” like it has much less capacity: it runs about 100 mV lower than the newer pack out to 1.2 A·h, then falls off the cliff. Looks to me like one of the two cells inside is fading faster than the other; so it goes.

I’m still thinking of using these to power some LED taillights, because they have a nice form factor and built-in latches:

Wouxun KG-UV3D - battery pack latch
Wouxun KG-UV3D – battery pack latch

Comments

2 responses to “Wouxun KG-UV3D Batteries: Age and Cycle Effects”

  1. Baofeng UV-5RE: BL-5 Battery Overview | The Smell of Molten Projects in the Morning Avatar

    […] I mentioned I was thinking of repurposing the nearly unused lithium-ion batteries from the Wouxun KG-UV3D radios for a blinky light, Dragorn of Kismet introduced me to his Baofeng UV-5 radio. The radio itself […]

  2. Baofeng BL-5 Battery: Initial Capacity | The Smell of Molten Projects in the Morning Avatar

    […] that with the Wouxun batteries (plotted with Gnuplot, rather than a screen […]