Introduction: Daily Driver E-Bike

About: I am Undergrad Electrical Engineering student who is DIY enthusiast and like to share information.

My Goal is to convert a $99 bike to e-bike with a budget less than $700 and use my bike as my daily driver.

Since I am focusing on battery life cycle, I want it to last much longer as possible. I am using BMS(Battery Management system) and a charger that was able to charge the battery at 80%.

Any suggestions and comments are welcome.

Thanks

IK

Step 1: Parts Needed

Step 2: Battery Design

The battery I am using is Samsung 25R 18650 2500mAh 20A Battery

Specs (I got from IMR.COM)

  • Nominal Capacity: 2500mAh
  • Nominal Voltage: 3.6V
  • Protected: NO, UNPROTECTED
  • Dimensions: 18.22mm x 64.80mm

Weight: 43.71g

My Motor

  • Voltage: 48V
  • Power: 1000W

I need at least a battery pack that supply 48V. I decided to go with 52V setup. 14S and 5P.

In Theory, I am getting

3.6v*14s= 50.4V

2.5Ah*5p=12.5Ah

and single 18650 has 3.6V*2.5Ah=9Wh. Therefore my overall Watt Hour will be:

Watt hour =Amp hours of cell *nominal voltage of the cell

Wh = 50.4V*12.5Ah=630Wh

Step 3:

Step 4: The Overall Design

Step 5:

Step 6: Testing the BIke

Step 7: To Be Continued...