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By Jerome, August 18, 2010 4:51 pm

So I got my batteries and my charger. It took 6 days. I still paid $57 of shipping!!! ( I was a heavy package, around 4kg (8.8lbs) )  That charger is huge. I can charge four 22.2V(6S) battery at once! That is really nice! My 250W can give 13A at 12V. I will measure with my multimeter see if the charger can deliver that much. I have to be careful because the fuse of my Fluke is 10A!

I just tested the scooter with one battery and I am more then happy with the speed! I hit 30km/h (18-19Mph) which is perfect!

I have a nice video and great data. I am writing a post about it.

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By Jerome, July 23, 2010 6:00 am

When I was in Calgary doing my intern at Solarbotics, I when to this store called Power in Motion that specialize in urban electric transportation.  They had this neat demo wheel of the inside of a hub motor.

Here are the hall effect sensor. There is 3 sensors.

Here you can see the slot inside the shaft where the wires can travel.

There was also this neat battery. 48V 10.5Ah lithium battery. It weight 3.4Kg (7.5Lbs)

That could fit in my scooter. The only draw back of those specific battery is the continuous current discharge. It is very low. I think it is 2C so 20Ah… the motor consume about 4Ah with no load and I get surge current of 70Ah.

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By Jerome, June 19, 2010 1:38 pm

The guys working on the Phoebus project, which is a 100% electric car, are testing these batteries.  I was able to grab some pictures and informations on them. The Phoebus project is a final engineering project done by mechanical and electrical engineering students at the University of Sherbrooke. I know a few guys on the team.

Those are LiFePO4 lithium battery. They are very big.  They have a nominal capacity of 14Ah and a continuous discharge rate of 10C ( 140Ah) which is not a lot.

Yep, those are big! Will not fit in my scooter! They are too wide for my scooter.

Model number is F014 and it is manucfactured by EIGbattery.

The maximum discharge rate of those battery is very low, 10C. Normal RC lithium battery are now in the 30 to 40C. That is 40 time the nominal capacity, so when you have 5Ah that is 40*5=120Ah continuous discharge!

If I choose the EIG battery, I would use the C008 , C015 or F010. The other models are very long (20cm) and large (15cm).

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By Jerome, September 7, 2009 1:13 pm

I order some lithium battery for my scooter.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=9177

Spec.
Minimum Capacity: 5000mAh
Configuration: 4S1P / 14.8v / 4Cell
Constant Discharge: 20C 20 x 5 = 100A constant discharge
Peak Discharge (10sec): 30C 30 x 5 = 150A burst
Pack Weight: 536g
Pack Size: 148 x 49 x 33mm
Charge Plug: JST-XH

I got 2 of those battery, when charged a battery like this equals to 16V. In series I will get 32V. I plan to have 4 battery like this. No not 64V it will be 10Amps at 32V. I only bought 2 for the moment so I could test it out first.

Choosing the battery voltage was hard. I could of bought 18.5V, so once charge that would o around 20V, so this mean I would have 40V in serie and my motor can got up to 39.5V. This was sort of perfect. I could of seen the real maximum speed I can get with my scooter ( one of the major goal of this project ).

I choose 14,8V for a couple of reasons. First, all the cheap charger I found, would only charge 14,8V packs. Second, I could use those 14,8V pack in future project like a segway and 3kg sumo robots ( The motors I am looking for run on 14V ). Third, I would of needed to buy a separate cell balancer because my current charger does not have that. And also, if I decide to make a other scooter and get lower wattage motor, they all seem to run at around 30V and lower.

One day, I might and would love to try at 40V, the max rating of the motor. I hope I could get a sponsor for the battery, that would help.

I also got some cheap charger, the charger I got has built in balancer. Balancing the cell mean that each individual cell are check to be sure that they all have the proper voltage before been used. This prevent damaging the pack if one cell could be discharge to much, below the recommended voltage.

http://www.hobbycity.com/hobbycity/store/uh_viewItem.asp?idProduct=2055

I also bought some wire extension for the balacing cable. I will be able to only get the cable out of the scooter to make easy charging. I bought 2 charger so I could charge both battery at the same time! I might have a charger on board of the scooter. The only drawback is that the charger works only on 12V, so I need a power adapter to get 12V. At home, that is not a problem since I use a old computer power supply. If I bring my scooter at school, I might need a adapter for the 12V on board.

Since the beginning, I am think about a version 2 of this scooter. The main modification would be using inflatable rubber wheels. Going 36km/h on 5inch plastic wheels is pretty cool but makes a lot of noise and breaks the wheels. In Québec, the roads are not pretty, so I need other kinds of wheels. I order from AllElectronics.com and I did receive my order. The wheels are cheap but the gearbox are pretty nice.

The gears you see are planetary gear box on your left  and a roller bearing on your right hat only spin in one direction. Like the pedals on your bike. They both match perfectly and I already have ideas how to use them. It is going to be really easy! Can’t wait to start that project.

I also added a Donation button, I have seen website that had those and said, why not? So if you love what I am doing and would love to help me buy more battery, please make a donation!