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I have this scooter:

http://www.monstermotorscooter.com/e-500.html

It takes those big batteries all the scooters take. I was looking at these charger packs that have a 5v lipo battery in them:

http://www.ebay.com/itm/Ultrathin-50000MAH-2-USB-External-Power-Bank-Battery-Charger-Pack-for-Cell-Phone-/401033102413?hash=item5d5f6f844d:g:WpEAAOSwzLlXgRji

I was wondering if I could take a few of those and wire them together to be like 15 or 20 volts and hook that too the scooter? I could make it go 30+ miles I think with that much power. Would the batteries get hot or something? Would it be safe to wire them together for increased voltage? I think if I just hooked 1 to it it would go too slow, because only 5 volts.

Okay I reworded this for a more detailed example which will give me the same solution that I'm looking for.

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closed as off-topic by Dave Tweed Sep 1 '16 at 11:46

This question appears to be off-topic. The users who voted to close gave this specific reason:

  • "Questions on the use of electronic devices are off-topic as this site is intended specifically for questions on electronics design." – Dave Tweed
If this question can be reworded to fit the rules in the help center, please edit the question.

  • \$\begingroup\$ Impossible to tell without more specs for the drone. What battery is it supposed to take? Note that the power packs include "added components" of their own for charge/discharge. \$\endgroup\$ – pjc50 Sep 1 '16 at 10:23
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    \$\begingroup\$ 5V LiPo? Never heard of that before. Maybe you mean 3.7V LiPo with a built in boost circuit to raise it to 5V? Not sure how chaining those together would work - could get nasty with all that switching going on... \$\endgroup\$ – Majenko Sep 1 '16 at 10:28
  • \$\begingroup\$ Can't you just pull the batteries out of the packs though? and there isn't really a drone I'm just saying like ...hook it to a 20v motor, for example. \$\endgroup\$ – Wayne Filkins Sep 1 '16 at 10:29
  • \$\begingroup\$ I'd like to know how they managed to fit 50,000mAh into a small package like that. Best I can do is 15 18550 batteries in parallel, at 270mm long - considerably bigger. I haven't seen any batteries that kind of size with such a huge capacity, certainly not for such a low price. I suspect they are actually 50,000 mWh not mAh, which at 5V would equate to 10,000 mAh. \$\endgroup\$ – Majenko Sep 1 '16 at 10:49
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    \$\begingroup\$ Short answer : No. Even if they actually deliver the rated 50Ah capacity (highly doubtful) it'll be at such low power (like 1A for 50 hours) it won't even move a scooter. You need cells that can charge and discharge FAST. And ideally, ones that last more than a hundred charge/discharge cycles. Look for charge/discharge rates, AND lifetime (no. of cycles) in battery specs BEFORE you buy. This one says "circle time : 1000 times" but at unknown charge rate and unknown final capacity : no good. \$\endgroup\$ – Brian Drummond Sep 1 '16 at 10:49
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a) The battery spec from the scooter page is: "Nylon handled pack, 24V/10AH pack,(2) 12V/10AH valve regulated, rechargeable". The scooter is 500W, which requires 20A at 24V.

(You originally mentioned a drone, at 20V, and then changed the example!)

b) Ebay specs and Chinese battery specs are often unreliable to fraudulent. I have a pack of the same size that's 10AH not 50AH. Their quoted max output is 2A, let's choose to believe that for the moment.

You need 20A, the packs might put out 2A. So you need (at least) 10 in parallel. You also should be close to the 24V nominal voltage of the official battery. So you need to stack 5 in series.

This results in a "10P5S" pack of 50 powerbanks as the minimum requirement.

(Each of those packs is a Lipo prismatic/"pouch" cell with a nominal voltage of 3.8V and a small circuit board to do the charge/discharge voltage conversion.)

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  • \$\begingroup\$ And the capacity - even if honest - will be that of the 3.7V cell inside, so you'll see 37Ah (minus conversion losses) at 5V output. \$\endgroup\$ – Brian Drummond Sep 1 '16 at 11:17
  • \$\begingroup\$ I have a pack of the same size that's 10AH not 50AH. -- That ties in with my comment above about them mixing Wh and Ah on their specifications to make it look better. 10Ah at 5V is 50Wh. \$\endgroup\$ – Majenko Sep 1 '16 at 14:32

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