Welcome to our second E-Bikes 101: Electric Bike School module! In our last article, we talked about the difference between mid-drive motors and hub motors. In this module, we will be talking about the importance of the equipment that powers these motors - the battery.
This may be a bit confusing at first, as when you start looking at battery statistics, you get a bunch of stuff coming at you like Ah, (Amp-Hour or Ampere Hour), V, (Voltage), and Wh (Watt Hour), which are important measurements of a battery’s charge, but might not mean much to someone who doesn’t know the significance. Well, we’re here to teach you!
AND NOW, FOR SCIENCE:
Here is some common battery terminology.
1. “Ah” is short for Ampere Hour, or “Amp-Hour,” and it is significant because it is a unit to measure a charge, not based on power output, but by time. Basically, how long a charge can be withheld for a certain amount of time. This type of measurement helps determine battery capacity.
2. “V” stands for “voltage,” or “electric potential difference.” Voltage is the measurement of electric potential of a unit of positive charge, from it’s start point to its finish point. (Think positive charge to negative charge on a AA Battery, usually at 1.5 volts). The longer the distance, the weaker the charge becomes, so you have to increase electric potential to make sure charge completes its run with enough juice to power something, without overloading it.
3. Watt Hour, or Wh, is what is calculated when you multiply “Ah” by “V.” Watt hour is the measurement of energy sustained throughout the entirety of a charge’s duration. Please note that this is not POWER calculation, (generated energy per second), but a calculated measurement of energy needed to maintain charge until it simply cannot. This is a measurement of a battery’s capacity can be before it needs recharging or replacing.
Phew! Science is hard.
So, that’s all great. But what does this have to do with electric bicycles?
Like it or not, every electric device we use runs by these units of measurements in some way. Your cellular phone, your batteries in your TV remote control, the massive batteries in your cars, the light bulbs in your house, all run on those same rules of electricity. The batteries on e-bikes work the same way.
BATTERIES ON E-BIKES:
The Biktrix battery for the Juggernaut Classic Series bike chassis.
As you can see, these batteries are a lot larger than some batteries you may be used to seeing. These particular batteries made specifically for the Biktrix Juggernaut series, come in 48V in terms of voltage, and have versatile and unique Ah levels custom to your needs (12Ah, 17Ah, or 20Ah).
If we go back to our little multiplication equation on how we get Watt-hour, (Wh), we can determine that there are varying batteries with varying battery capacities for an e-bike. An example would be that 12Ah x 36V would be a smaller battery in terms of overall capacity and in terms of weight, but a larger battery, like 20Ah x 48V, would maximize your ability to ride longer. This affects performance through enhanced longevity of the battery’s charge, affects the weight of the bike as a larger battery is on the frame, but opens up your ability to utilize maximum power, for longer, using the pedal assist feature.
These same batteries can power hub-motors, and mid-drive motors, respectively.
Thank you for reading article number two on our electric bike school modules. Next, we will be talking about battery maintenance, and steps you can take to get the most out of your battery.
About Robert Bryn Mann:
Robert Bryn Mann is a Customer Content Specialist at Biktrix. A professional writer, he is happy to be working with a company that shares his passion for greener transportation options. When he is not working with Biktrix, he is writing stand-up material and scripts for film and TV.