Wednesday, June 5, 2019

Attachable 5AH LiPo "eBay battery" for mcHF

A number of eBay sellers have started making an attachable LiPo battery for the mcHF transceiver. The battery is listed as 5AH on eBay but is labeled on the battery itself as 6.8AH.



With included hardware, the battery attaches to the fold-out stand on the mcHF's housing and does not interfere with that functionality. In addition to the 12V output the battery also has two 5V USB plugs for charging a phone or other device.

The battery arrived poorly packed without sufficient packing material to keep it from shifting around in the box. It got worse from there.



Prior to charging the battery I opened it to have a look at the battery and supporting circuitry. As with the shipping package the battery was unsecured in the housing and would slide from side to side as the case was tilted.

Battery slides to the left...


...and to the right


The wires leading to the USB jacks changed gauge halfway there via a poor solder connection wrapped with electrical tape.

Battery, charger and hardware for attaching to mcHF


After securing the battery with double-sided tape, resoldering the USB connections and shrink-wrapping them, I charged the battery with my own charger, tossing the included one into the circular file.

Then I set up the battery analyzer to discharge the battery at 400mA - the receive current draw of the mcHF. This resulted in a measured capacity of 3.4 AH.

At a lower discharge rate, and if discharged to a lower voltage than I would prefer, the battery probably will give 5 AH of capacity so the advertising is correct although the battery's label is overly optimistic.

If you have a mcHF and are tempted to add a modular battery I'd recommend avoiding these eBay batteries like the plague.



A better solution would be to buy an empty case (if possible) and add a battery and protection circuits from a reputable manufacturer.
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UPDATE (26 June 2019):

A comparison of a lower discharge rate (100mA) shows little difference in battery capacity from the 400mA discharge rate.


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3 comments:

  1. Hello John, is there no protective circuitry in the charger like there is in the UV-3R Baofeng chargers? Well, most of the time the price says something about the quality. Sometimes you're lucky but in this case you're not. Thanks for the warning. But at least you can probabely build something yourself using the housing you got now. 73, Bas

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    1. GM Bas, the battery itself was not wired to any output circuitry to protect it from be discharged too deeply or too rapidly (as in the case of a short). I'll see how the battery performs with the mcHF and will then see what size battery I can fit into the case - maybe a series of 18650 Li-Ion cells.
      73 - John

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  2. I bought one, the battery was crap and swelled. So I put a 10pack AA holder in for 2500mah rechargables. I took out the charging gear and usb circuit. It works fine enough. I just open the case and pull the AA batteries out to charge them.

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