Portable AC Outlet

[OneWheel]

 

Just wondering if this portable AC outlet could charge the ninebot one P battery while it is turn on. Could this cause any potential problems?

http://www.newegg.ca/Product/Product.aspx?Item=N82E16875949298&cm_re=portable_outlet-_-75-949-298-_-Product

Thanks.

[dmethvin]

No, it won't work. The main clue that it won't do much for you is the small number of cells in the unit compared to the Ninebot.  The specs say it has a max of 85 watt output on the AC outlet and the Ninebot has a 130 watt charger. If you plug it in the charger will draw too much current and the AC inverter in the "portable AC outlet" will most likely shut down.

In any case, a charging process of "DC battery to AC to charger back to DC" is really inefficient. If you have a high-current DC source like a car battery you could use a DC-to-DC inverter, like mentioned here: http://forum.electricunicycle.org/topic/867-charging-in-a-car/?

 

[esaj]

Like dmethvin said, the charger will likely overload the AC-output side, and the protections will shut it down.

15 minutes ago, dmethvin said:

The main clue that it won't do much for you is the small number of cells in the unit compared to the Ninebot.

To continue on this, don't get fooled by the large mAh-numbers. Milliamperehours or amperehours are somewhat misleading, as they don't take the voltage into account.

For example, if you take the cells from a Ninebot E+ -battery pack (around 320Wh, 15S2P, 2900mAh cells), and wire them all in parallel, you get out "only" 3.7V nominal voltage, but the mAh -capacity of those cells will be 30 times the capacity of a single cell, so in this example 30 * 2900mAh = 87000mAh (87Ah). But the total watthours is still the same as with higher voltage: 3.7V * 87Ah = 321.9Wh , 55.5V * 2.9Ah * 2 = 321.9Wh  (the times two is there, because there are two packs in parallel, 15S2P). The amperehours in 15S2P is still "only" 2.9Ah * 2 = 5.8Ah (5800mAh).

There are 8 cells in that charger-pack you linked, 18000mAh / 8 cells = 2250mAh (2.25Ah) per cell. The total watthours for that pack is 3.7V * 2.25Ah/cell * 8 cells = 66.6Wh. So even if it would work otherwise, and the conversion to AC and back to DC would be lossless, it couldn't charge more than that into your wheel.

[Colestien]

  I bought a 115volt account unit that goes in my cigarette lighter.  I tried it.  I unplugged everything and didn't try again after the charger light started blinking.  It never blinks, always a steady red or green. 

  I'm sure there is one made that would do the job,   But they cost so much I could buy another Wheel instead.

[dmethvin]

Yeah, for the standard car inverters if you figure at most they can draw about 10 amps from the cigarette lighter plug that's only 10a*12v or 120 watts. Assume some losses in conversion and at best you might get 100 watts to an AC device plugged into the lighter without blowing the fuse. Some inverters come with clamps you can attach directly to a battery to pull more power but that would make them a pain to use.

[Rui]

Hi sir, try this. I'm not using it but it may help. I think you just have to change the terminal socket to fit in to the ninebot.  https://wheelive.com/store/product/portable-power-bankexternal-backup-battery-for-self-balancing-electric-unicycle/

 

 

[dmethvin]

13 hours ago, Rui said:

Hi sir, try this. I'm not using it but it may help. I think you just have to change the terminal socket to fit in to the ninebot.  https://wheelive.com/store/product/portable-power-bankexternal-backup-battery-for-self-balancing-electric-unicycle/

The Ninebot uses a lower voltage than many other EUCs, so external battery packs made for other EUCs should not be used. The manufacturer may be able to provide one that does work though.