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Adding Extra Battery and Power Bank?


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Hello all

So the time has come to attempt some mods for my 16in gerneric its called a Zip Wheel, Its not a bad low end model i get about 6 miles out of the battery and the speeds ok.

The other day i was enjoying a ride around my area and decided to push the limits and before long i noticed i only had one bar left and a hell of a walk :(.

I found that there is loads of space in this thing as its a 16in i want to add a second 60v samsung battery with a switch to change banks, easy enouth right? Then it dawned on me why dont i have a mobile/whatever 12v/5v output for those i forgot to charge my dam phone moments and possabley lights aswell, all from the second battery :). Im not to bad with a soldering iron or wiring i was just wondering if theres any reason why i cant do this?

Also anyone know of anyone else thats done this before?

oh and last thing a tracker will also be ran from the second battery as my last EU got robbed from me at knife point, they're not getting away with it TWICE!

Alesha.

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Assuming you are going to use a similar battery to the presently installed one, why would you not simply fit them in parallel rather than switch over. A switch is also a point of failure that could end up face planting you if it fails.

You would half the internal resistance, raising the voltage at the wheel, therefore lowering the current for a given power demand. I.e. You would go further on a parallel pair than you would on two single batteries. The charge connection could be parallel as well, it would just take twice as long to charge.

Are you aiming to buy a whole pack or build it from individual 18650 cells? What I haven't got my head around, and maybe someone can help, is how the packs keep the cells balanced, I.e. The individual cells in a pack won't all be exactly the same capacity so cell voltage can drift, resulting in an individual cell overcharging or being drained too low. Is some form of battery management circuitry incorporated to even the cell voltages? 

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Yes many members have done it. You can put a second battery pack in parallel if you have the extra space so that you do not need to swap batteries. Just remember to have both battery packs charged at the same level before combining them. You will need 2 Y connectors for this process. You may need a dc to dc step down converter for 12v/5v output. 

Here is a link to a cheap 2900 mah Samsung battery pack being sold by Banggood.com.

http://www.banggood.com/2900mAh-Electric-Unicycle-Battery-18650-16S-Lithium-Ion-Battery-60V-p-1006976.html

 

 

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16 hours ago, Keith said:

What I haven't got my head around, and maybe someone can help, is how the packs keep the cells balanced, I.e. The individual cells in a pack won't all be exactly the same capacity so cell voltage can drift, resulting in an individual cell overcharging or being drained too low. Is some form of battery management circuitry incorporated to even the cell voltages? 

Yes, there's a BMS (Battery Management System) -board inside the battery pack(s) that handles balancing of the cells as well as various protections (under-/overvoltage, overdischarge = overcurrent, short circuit, and sometimes temperature protection). The multi-pack configurations vary between wheels, for example Firewheels use only one BMS inside one of the packs, whether it's F132 (1 pack), F260 (2 packs) or F528/F779 (4 packs), and also the configurations are a bit exotic in those (16S1P for F132, 2  * 8S2P in series for F260, 4 * 4S4P in series for F528/F779). Some other multi-pack wheels might have a separate BMS in each pack. I've got 4 custom packs (16S1P) each with their own BMS, as I thought that'd be safer (a failure of a single pack won't mean complete power loss) and I can put them in and take them out individually, should I need to.

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  • 1 month later...
  • 1 month later...

Thanks for all the info. I have a TG-T3 ( http://www.banggood.com/132Wh-T3-Electric-Wheelbarrow-Balancing-Unicycle-15-20km-Endurance-p-949305.html)  and im looking for increase my kms....

 

I have a 132W battery. What its better. Another 132 W or increase to 174??view?usp=sharing

The only I need is the battery (http://www.banggood.com/2900mAh-Electric-Unicycle-Battery-18650-16S-Lithium-Ion-Battery-60V-p-1006976.html) and conectors fot batteries? Thank you for all 

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Thank you so much @Lovely! :D

Now I havn´t the battery, but its in my Wishlist. 

A doubt that I have is not whether the two batteries (connected in parallel) can be charged at the same time (via connector unicycle) or if I have to charge the batteries separately.
I'm looking to increase my autonomy kms !!!

Thanks

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When you will have these two 132wh equal battery packs, just charge them on your unicycle, separately first time and when it's done they should have about the same voltage. Then connect them together in parallel. If both battery packs are brand new and fully charged, then its ok to connect them together in parallel, so they will balance each other.

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42 minutes ago, Óscar Ramos Melero said:

And when I have to connect it, the voltage will be aprox the same... but how many is te "aprox" difference? 10 volt? 1 volt? 0.1 volt? 0.01 volt?

I'd say aim for less than 1 volt of difference, the smaller the difference, the better. The batteries will "equalize" once connected, but if the voltage difference is large, there will be a large current rush between the batteries, which can cause overheating. Also the connectors shouldn't spark (at least as much) the lower the voltage difference is when connecting them.

You can charge them through a single charge port as long as the current isn't too high, just parallelize the charging wiring also. If you are unsure about things, look around the forums or ask questions, the packs can be really dangerous if the connections are made wrong.

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You will need something like this, on the picture. Check your connections also. It would be good if somebody could confirm this! Yes, as esaj said, be very careful when working with the batteries! Also, if you will short plus and minus, by mistake, even for less than a second, there can be quite impressive fireworks and the connections can be destroyed in one click, and the melt, red hot metal could drop on your table or somewhere else. It is the best final, actually..

Parallel-Battery-Pack-Connector.JPG

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Hace 1 hora, precioso, dijo:

No soy un especialista, Pero por Lo que sé, si ha Conectado Estas Baterías 132wh paralelo, se podria cobrar Como el paquete De Una Batería, Solo El Tiempo de carga Dębe Ser Más Largo.

I buyed cables but not battery.

I buyed this:

http://es.aliexpress.com/item/T-Converter-Plug-2-male-1-female-with-16AWG-Silica-Gel-Cable-L100mm/628941751.html

and:

http://es.aliexpress.com/item/1-to-2-RC-XT60-Dual-Extension-Parallel-Battery-Connector-Cable-for-DJI-Phantom/1840790605.html

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3 minutes ago, Lovely said:

You will need something like this, on the picture. Check your connections also. It would be good if somebody could confirm this!

Yes, a parallel-connector like that is needed. Check that the connectors are the right kind (XT60 in the pictures is pretty usual, as far as I know).

 

3 minutes ago, Lovely said:

Yes, as esaj said, be very careful when working with the batteries! Also, if you will short plus and minus, by mistake, even for less than a second, there can be quite impressive fireworks and the connections can be destroyed in one click, and the melt, red hot metal could drop on your table or somewhere else. It is the best final, actually..

You mean like this:

MVubVBq.png

I had earlier measured some currents with my multimeter, and forgot the measuring probe in the 10A -hole. Then I decided to check the battery voltage, shorting the plus and minus through the meter... BMS cut the power, didn't even blow the fuse on the meter (but it did melt the other probe and weld pieces of metal inside the connector as the probe head exploded into shrapnel). Yeah, these things pack quite a punch... luckily the shunting wire from the packs was already cut at this point.

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10 minutes ago, Óscar Ramos Melero said:

I need XT60 and T-plug. 

Electic unicyvle  XT60 male
                          T-Plug male
BATERY 132 XT60 Female
                     T-plug Female
NEW BATERY 132 XT60 Female
                     T-plug Female

Sounds like you then got the right connectors already. Just take care to check that the polarities on the batteries are right for the connectors (they should be, but it never hurts to check), and that the voltage difference is minimal before connecting them.

 

8 minutes ago, Lovely said:

Yes, absolutely ! That's what I mean! Look at this one as well !  :D 

IMGP6689.JPG

Haha, looks like I'm not the only one to do that mistake :P  Sure taught me to check the wiring first before plugging the probes anywhere ;)

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