Electric Bikes - E-bike introduce & advice from engineer

I make up a PPT file ,but it's too large.So i need to post again and again.

I am an electronic engineer, designed the controller before. Here I will show the base knowledge of the E-bike include the whole, battery, controller, motor and charger. And tell you what we should care when we build a e-bike. Any questions or need help, don’t hesitate to send me email. I will try my best to answer.

1.mini e-bike
Someone calls this type e-scooter. It’s very light and low speed. U can pedal while the battery is off. Maybe it’s the girls' love. It's well on the plat road but not on the mountain road. It's the folding type too so easy to be taken away.

2.e-bike

This model is very similar to the bike, and this is the e-bike we refer to commonly. It can be pedal while the battery is off. Based on the bike, there are folding type, mountain type, mini type and so on.

As the pictures below, used the Li+ battery, folding type, the whole weight is 20kg and the max-speed is 30km/h, the range is near 40km. The price in China is about $400~500.

2.e-bikes:li+ battery

3.E-motorcycle

This model is more comfortable for the rider and faster than the e-bike. It use the lead-acid mostly for more capacity. So it's very heavy. It can't be pedal. U will be embarrassed when the battery is off or in failure.

This type's whole weight is over 100kg I'v seen, the max speed is 80Km/h, the motor is 2Kw, disc brake. But mostly used on road is 500~800w, speed is about 40~50Km/h.

4.E-trike & E-vehicle

5.Segaway

1.Lead-acid Cell

Eg.(17Ah)
Normal voltage: 12V
Capacity: 17Ah
Dimension (mm): 77*167*187
Weight: 6.5 Kg

Lead-acid package

Voltage:12V/Cell(11~13.8V)
24v: 2cells in serial;
36v: 3cells;
48v: 4cells

Lead-acid Package chart(36V)

2.Li+ Cell

Eg. 10Ah
Nominal voltage: 3.7 V
Capacity: 10 Ah
Dimension (mm): 18*66*133
Weight: 0.38 Kg

li+ package

Voltage: 3.7V/cell(3~4.2V)
24V: 7 Cells in serial
36V: 10 Cells in serial

li+ pacakge

Li+ Package chart(36V)

li+ balance & protect board schematic(typical).

As the above, the lead-acid battery is simple than the Li+ battery. There are not PCBs. Usually, the lead-acid has more capacity but heavier. For example, as the 36V/10Ah, the lead-acid battery's weight is 13Kg but the Li+ battery's is 4.6Kg.

There are several cells in both Li+ and lead-acid package. If one cell is done, the whole package is failure. As the li+, if the protect board is broken the package is in failure too.

When select the battery, we should care about the voltage, the capacity, the max discharger current, the cycle life.
1) Voltage idecide the controller and motor. For example, if the battery is 36V, the controller and the motor selected must be 36V. And the charger is 36V too.
2) Capacity decide the range. Higher capacity gets more range. We can measure capacity used the power resistor approximately.
3) Max discharger current decide the load. If the current over this max value, it maybe cause danger. Especially for the li+, it will make the protect board broken.
4) Cycle life decide the battery life. It must be the whole package's life not the cell.

We should charge the li+ battery every 2~3 months, lead-acid battery every month even not used. If install alarm system, it must be short.

The li+ battery is more popular. When select this, we must notice that the charge connector is different from the discharge. If exchanged, it may make the protect board broken. Balance board can make the cells work at the same voltage so the battery will work at max capacity. Some package doesn't use the balance board.

Some guy build the battery with 18650(another li+ model, used in laptop, 2.2Ah). This model can't work on the high current. To get more capacity, the cells must be in parallel connection. But more cells take more chance of unbalance and unsafe.

Hub motor(brushless)

Every motor base on the voltage and the power. For high efficiency, it should be used at the rated. The type of M3 is the gears inside. It can supply big torque.

Brush motor is used in the e-trike mostly. It can work at the high current and the controller is simple and safe.

The gear outside type motor is used few beacuse the noise and difficult install.

I'm guessing that English isn't your first language? You should have someone proof-read for you. With a highly technical subject like this it's important to be accurate in what you're saying, and even small mistakes make it very hard to read.

You should also pay more attention to your presentation. Put at least one space in between sentences if not two, and put spaces in between paragraphs when you change subjects.

On a more general note, I don't really understand what the point of your presentation is. You give a few vague general descriptions of different types of E-vehicles, list a few battery specs without giving a brand, type, or link to where to get it, and then throw up a wiring diagram for a controller without explaining it. You never really give any advice or say anything that isn't already part of the links in sticky threads.

If you put more work into your presentation, it might end up being very informative.

ToJakcBeNimble (http://www.bikeforums.net/member.php?u=77275):
You are right.I am from China,and sorry for my English.All the e-bikes and batteries I refered are the typical mode and the PICs copied form web.Actually, there are many many of types I can't describe in one topic.I try to explain the base knowledge for everyone.Maybe most reader just ride not DIY.

Thanks for ur advice.I would try my best to improve.

Hi Similor,

Remember to type one space after each period and one space after each comma. That would make your writing easier to read.

Thanks,
Ambrose