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Maestro rechargeable battery packs

Mark Griffin
Mark Griffin Member ✭✭

I am considering a Flexradio Maestro. I realize you can power it by A/C. But I also know that you can install a battery pack in the back of the unit. Does anyone have any recommendations on a battery pack that will fit in the Maestro? Not sure if it can be charged while in the Maestro or not. But I don't have any problems with taking it out of the unit to charge it.

Mark KB3Z


  • Mike-VA3MW
    Mike-VA3MW Administrator, FlexRadio Employee, Community Manager, Super Elmer, Moderator admin
  • David Decoons, wo2x
    David Decoons, wo2x Member, Super Elmer Moderator

    Also Flex recommends charging the pack out of the Maestro. This is for safety reasons.

    Not all battery packs are created equal with charging requirements and is one reason no internal charging was available. Also as I mentioned, safety. Think hoverboards and the fires started by charging those.

    and last, when charging LiPo battery packs, do not leave them unattended just a precaution


    Dave wo2x

  • Martin AA6E
    Martin AA6E Member ✭✭✭

    Has anyone ever heard of a Maestro fire? :)

    I normally operate via ext 12v supply and only install my mogix when full portability is required. It's about battery management more than safety.

    It would be nice if Maestro had "full service" battery support. (Internal charger & battery charge indicator, switchable mains/battery operation, etc.) Some day...

    73 Martin AA6E

  • WX7Y
    WX7Y Member ✭✭✭

    All LiPO can catch fire, one thing to watch with the Maestro is that when the Battery begins to swell it will push on the back of the screen and cause black spots on the screen.

  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭

    New Maestros have not been available from Flex for roughly a year. Did you locate a used one? “A” or “B” model?

  • Mark Griffin
    Mark Griffin Member ✭✭


    I am thinking about ordering a new one. Online it says 4th quarter 2022. I assume there in a long waiting list.

  • Neil D Friedman N3DF
    Neil D Friedman N3DF Member ✭✭✭✭

    I suggest waiting until you receive the updated Maestro from Flex before buying a battery. It may have different requirements.

  • Mark Griffin
    Mark Griffin Member ✭✭

    I just placed my order. Time to just wait and see how long it will take.

  • Gord-VA7GP
    Gord-VA7GP Member ✭✭
    edited January 2023

    I found this 40W / 20,000mAh battery on AliExpress. I bought it based on the physical dimensions, and it easily fits inside the Maestro B recess. Published dimensions are: 141mm long, 66mm wide, and 16mm thick.

    I especially like that this battery-bank features USB-C charging - a personal mainstay since my Pixel 2 days (2017, 5yrs ago), and all my current Dell & Apple laptops, Kindles, etc. USB-C everywhere! The capacity-display is handy but I can only view it when this battery is outside the Maestro... when installed, the Maestro's built-in USB-A cable orientation forces me to turn the display inward.

    For $25 Cdn, I bought 2x of these, and they work well for me. In case the URL above dies, here's a screenshot to help guide others:

  • Gord-VA7GP
    Gord-VA7GP Member ✭✭

    Summary: I got burned 😮☹️

    My latest Aliepress 40Wh/20,000mAh battery seemed to charge fast. Very fast. Too fast.

    And in-use, the Maestro ran it down quite quickly. Hmmmm.... out came the Big Hammer:

    Yeah - tiny battery, couple of large metal plates to give it some "heft". Completely Fake.

  • Gord-VA7GP
    Gord-VA7GP Member ✭✭

    Here is another battery which seems to work (by this I mean it takes the expected 3hrs to charge, and has run my Maestro for at least 3hrs - at which point it was not fully depleted):

    This battery-bank fits beautifully into the Maestro,with the middle USB-A port lining-up well with the internal cable. It's too bad the orientation forces the "gas-gauge" paw-print to face inward, where it cannot show me the remaining capacity.

    There are a couple of excellent Off-Amazon reviews for this bank, which lend comfort after my AliExpress burn:


  • Butch
    Butch Member ✭✭✭

    I got a surprise this morning. My Maestro (A) was sitting doing nothing, plugged in but not turned on when I heard it make a snap noise. Turns out it's battery had expanded to where it popped the battery cover off! Thankfully no damage to my Maestro.

    I've been using the Mogix 10,000mah batteries in it for years. I bought 3 of them and have been cycling them regularly and being careful not to leave them on charge too long, plus making sure they are not warm or hot when I reinstall them.

    Someone please correct me if I'm wrong but when the Maestro is plugged in to AC, it "does not" apply charging current to its rear mounted battery, right?

    This is the 2nd Mogix battery that I've had pop open. The first one I managed to catch early and it barely popped open, but this second battery really expanded!

    I think for now on I'll be leaving my battery out of the Maestro while it's sitting doing nothing. And also leave its batteries in a fire proof pouch, just in case.

    Butch, KF4HR

  • David Decoons, wo2x
    David Decoons, wo2x Member, Super Elmer Moderator

    There should only be a single USB A cable in the Maestro battery compartment on type A and B Maestro which plugs into the 2.1 A port on the battery pack. This does not charge the battery.

    all battery packs should be charged outside the Maestro (that is why there is no charging cable). Also battery packs should be charged under supervision. You hear of all these deadly fires in apartments started by unattended charging of e-bikes.

    If anyone is interested I have one of the original Polanfo gold color 20000M battery packs that last just over 4 hrs in the Maestro. $20 and I will bring it to Dayton. Shipping is a pain as carriers don’t want to transport LiPo batteries.

    Dave wo2x

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