Will adding one more battery improve my electric bike's speed?

Browsing on the internet we have found a curious question about the battery and electric bike speed, someone is wondering if with an extra battery it's possible to get extra speed. So, let's talk about the relationship between the battery and the speed.

The electric bike battery gives power to the motor and the ebike get's the energy to move all around: the battery pack represents the "car fuel tank" where the electric energy is stored.

If you drive a common car, adding an extra fuel tank will make the car faster? There the answer it's more clear and easy to understand. In fact that means that if you add an extra power source you will not get "extra speed" from an extra battery.

So, unfortunately, adding an extra battery won't make your ebike faster.

The speed is determined mainly by the motor and controller power, but it's correct to say that the battery voltage can influence the bike power and speed, but the Voltage parameter is already chosen by the electric bike producer and you can't swap your battery pack with a different one.

The main kind of ebikes that you can actually buy, use the 36 Volts or 48 Volts engine and battery pack, those configurations offer a different power output and performance. Obviously a 48 Volt engine needs a 48 Volt battery pack and vice versa with 36 Volts.

Let's go deeper in detail about those two configurations explaining what's different between the two motors.

Batteries: 36 Volt or 48 V?

So, what is the difference between 36V and 48V motors for electric bicycles? It is one of the topics that most intrigues the more or less experienced riders that are looking for a new ebike.

If you don't have a master degree in Mechanical Engineering, we're sorry but you won't understand anything. It is not true! We are kidding because it can be easily understood. Even if the theme is not the easiest, we will try to explain it well in a way that everyone can understand.

Explaining it in simple terms, the performance of the electric engine has to be considered in the whole kit with the battery pack. In fact, the batteries have features to keep an eye on to better understand the underlying differences between 36V and 48V systems.

We have the following parameters:

-Nominal voltage (Volt) 36V or 48V
-Ampere / Hour (Ah)
- Capacity (Wh)

Inside the batteries there is a set of elementary cells that serve to reach the desired voltage (Volt) and current (Ampere) value. Both relate to the battery and the higher these values, the longer the battery life will be. Let's take a practical example: Ah (Ampere / Hour) are like the fuel tank of a car.

"Ah" means: the unit of measurement of the flow of electrons, or current, through a circuit.
Ampere-hour (Ah): unit of measurement of the energy storage capacity of a battery, obtained by multiplying the current in amperes by the discharge time in hours. For example: a battery that delivers 5 amps for 20 hours = 100 Ah of capacity.

The "Wh" value will tell you how much ranger you can get from the ebike. considering the same setup and motor, higher is Wh, longer will be the range in miles that you can ride.

Motor 36V or 48V

So let's get to what interests us most. A 48V motor has a wider range of use than a 36V one and can be exploited more at lower rotation speeds. It means that it has more torque and it will be more performing in situations that require a heavier motor load, like for example off roading and while climbing. In fact it's the most chosen in e-Fat bikes, to provide more torque and acceleration.

To achieve this, however, you need batteries capable of delivering strong currents without prematurely deteriorating the cells. The higher the voltage, the lower the current will be with the same power output.

Here we find ourselves dealing with prices. The cost of the batteries depends on the Wh therefore, in order not to exceed the market price) batteries of about 360 Wh (ie 36V and 10A) are proposed as basic models for city bikes.

A 48V motor would be able to climb even on slopes of 30%, but it would need a battery of at least 48V and 10Ah which in total increases the price of the bike.
With a 36V engine, on the other hand, although less powerful, you can easily travel on public roads without exceeding the speed and exceeding the permitted limits.

Our opinion is therefore positive for both, but it is necessary to know for which type of route you intend to buy an E-Bike. For an undemanding use, a 36V motor may be fine within the urban context. If you want to use your bike for road types with greater inclination (and therefore also Off-Road) a 48V motor is definitely preferable!

Are you loking for your first electric bike? Please, give a look to the brand new Meebike Gallop, a powerfull urban fat bike powered by a 48 Volts motor and high capacity Samsung 48 Volt battery pack.