Ultramotor A2B Metro RC Lipo frame batteries

Ultramotor A2B Metro RC Lipo frame batteries

For e-bike geeks only: Here I show how I successfully installed two Zippy 10S 5800mah long lipos inside my A2B Metro frame. I bought three foot long aluminum bar stock two inches wide and an eighth of an inch thick from Home Depot along with a $25 big industrial pack of 2″ wide Velcro. I put a bend in the end of the aluminum bar to keep the batteries from slipping downward and then velcro’d the heck out of the aluminum bar and batteries to keep them in place and protected from chafing. I finished with two 6mm stop screws to keep the “trolley” in place once inserted into the down tube. I also had to extend the power and balance wires from the battery pack highest up inside the down tube.

Readers Comments (14)

  1. Can you share with us the battery specs to order and a good source to purchase them from.  Is there a cost savings involved with this solution over purchasing a stock battery pack?  Thanks

  2. I bought mine from a fantastic e-bike specialist in North London called Smartebike http://www.smartebike.co.uk – highly recommend! My battery is coming up to 4 years so its time for a change. What sort of range do you get with the Lipo batteries? I’m getting about 12 miles too at the moment. 

  3. im in north africa and batttery is dead is there a way i can fix it or maybe a workarround plz thnx

  4. Jan Hendrik Mangold December 18, 2020 @ 9:56 pm

    I also need to replace the original tube battery in my Metro. Apparently the Zippy 10S 5800mah is discontinued. Do you have a suggestion which other Lipo pack would work? Also, in your video the "switch module" wasn’t visible. Are you using the standard A2B one?

  5. the original battery packs for this a2b were rc type lipo or 18650 lion cells? thanks for a reply

  6. Sadly, I don’t know…

  7. where can you buy the stock a internal battery for the metro? I’ve been looking for weeks!

  8. I have an A2B Obree. The battery got bad and can’t find a replacement. Is attached to the rear wheel rack so, I don’t have those batteries inside the frame, just the controller and wiring. The battery have 2 pairs of cables going into the bike, any idea about them? Are 2 thick red & black and 2 tiny also red & black.

  9. I really like your hack. You did wire them up in parallel, right? When you speciify ‘long lupos’, I assume that you are referring to a specific configuration. I have  Googled the batteries you mention, but they look too thick. Could you indicate the aprox dimensions of the packs you used? Also, are you able to use the stock charger?

  10. The batteries are hobbyking zippy 5800 mah and are about $100 each which is far cheaper than stock. They are much higher output than stock, too.

  11. That’s good but why didn’t you just buy the battery pack that they make for it?
    Is there much difference in cost or performance or just did it out of curiosity?

  12. Thank you!! I would like to do the same,but not everybody know correctly how to do like you!! Do you can help me how to do this correctly?
    First, where to buy this battery pack, and how to connect the two battery to the bike.
    Thank you for your help!!

  13. crazyenergyprojects December 18, 2020 @ 10:32 pm

    The stock batteries have a very weak discharge rate as compared with RC lipos. I can accelerate a lot faster than with the stock batteries.

  14. Nice DIY battery!  I have that bike and am only getting 12 miles per charge.. Need a new pack… Was wondering if you had some details to share:

    What did you do with the relays and the bottom cap?  Thought the relays were needed to switch from A to B battery.

    How are you limiting the lower voltage cutoff?

    Are you charging one lipo pack at a time because i don’t know of any balanincing charger greater than 14s?

    Is that 10ga wire and 5.5mm bullet connectors?

    Great job buddy!

Leave a comment

Your email address will not be published.