The range of an electric bike is usually understood as the distance traveled on a single battery charge . More precisely, it is the distance for which the electric assistance of the motor is provided before the battery runs out. This is a parameter that is influenced by many factors during normal riding, including the way the motor is regulated by the rider. However, for comfort on an electric bike, it is an essential parameter , because it actually indicates how far the bike will be able to assist you like a real electric bike before you need to recharge it or just pedal like on a regular bike (however, an electric bike is heavier than a regular bike).

Similarly to the fuel consumption of a car, some e-bike manufacturers indicate the range in the form of the number of kilometers traveled, with the lowest assistance level set and therefore the minimum consumption of the e-bike (e.g. "range 130km") or in a certain interval of kilometers as the usual ranges in which the range can vary (e.g. 80-110km), which is a less accurate expression.

What affects the range of an electric bike?

Let's take a closer look at what determines the range of an electric bike:

1. E-bike battery capacity

The main indicator for assessing the range of a bike is the battery capacity. This expresses how long the battery is able to provide a certain electric current. It is given in Ampere-hours. For example, 10 Ah means that the battery can provide a current of 10 Amperes for one hour or, for example, 1 Ampere for 10 hours, etc. In general, the higher the capacity of an electric bike battery (more Ampere-hours at a given voltage), the higher its actual range will be.

To assess the performance of a battery, we simply multiply the battery capacity (number of Ampere-hours, Ah) by the average battery voltage (number of Volts, V) at which the battery operates. This gives us the performance per time, given by the number of Watt-hours (Wh). For example, a battery with a capacity of 10 Ah and a voltage of 36V has a performance of 10x36, or 360 Wh (Watt-hours).

Riding an electric bike with the lowest level of assistance consumes at least 4 - 5 Wh per kilometer of distance (depending on other circumstances, described below)

E-bike range calculation

By dividing the number of Watt-hours by the energy consumption per 1 km, we get the number of kilometers the battery will help us:

With a minimum consumption of 4.5 Wh and a 10 Ah/36V battery, we get 360 Wh divided by 4.5 Wh = 80 km, as the theoretically possible maximum range of an electric bike.

For example, with a capacity of 16.5 Ah and a voltage of 36 V, this equates to 594 Wh/ 4.5 Wh = 132 km, as the nominal range of an electric bike, with minimal consumption.

For an achievable range of 120 km, the battery should have at least 15 Ah at 36V.

With a more comfortable higher level of assistance, when the rider "drives" more, the consumption on a regular e-bike (250W) can fluctuate between 5.5 and 10 Wh. When starting off, riding uphill or riding with direct engine engagement (if the bike has such a function), the consumption can climb to tens of Watt-hours per kilometer. With batteries with a larger capacity, it is likely that the total distance on one charge will not be covered in one go, but there will be breaks during it. If they last longer (1 hour or more), they will help the battery recover in the range of 5-10% and thus extend the total range even further.

2. Style and nature of riding an e-bike

It is logical that the range is significantly influenced by the weight of the rider, the nature of the terrain (rough surface, hilly terrain, frequent starting, headwind, etc. reduce the range) and the riding style - especially the selected assistance intensity. The range can be extended by switching off the assistance when riding on a flat surface or on a gentle descent, by pedaling more intensively (applies to the frequency sensor), by riding more smoothly, etc. If the battery is loaded with higher currents (high level of assistance), the chemical structure of the battery will not be able to release the same energy as if you were to discharge it slowly. The same applies to temperature changes. In frost or even at temperatures around 40 °C, lithium batteries have worse properties in terms of usable capacity.

Of course, the technical condition of an electric bike also has a significant impact on its range - the choice of tires and their inflation, brake adjustment, chain lubrication and wheel center adjustment, pedaling, condition of bearings, etc.

There are many e-bike models on offer, where the range is objectively extended thanks to a higher battery capacity, which can be up to twice as large (up to 25 Ah) for the same external shape. Thus, it is able to emit the same amount of energy for twice as long, and the real range on a low level of assistance then exceeds 150 km.

The range of an electric bike can be significantly extended if a more skilled rider maintains the cruising speed of the electric bike above 25 km/h for a long time (when the motor assistance is disconnected by itself) or switches off the assistance while riding and pulls the bike more with his own power (If you ride mostly without a motor, you can travel several hundred kilometers on a single charge). Such an approach leads marketing staff of some, even renowned brands, to give distorted or unrealistic range values. For the parameters we provide for all electric bikes sold, the range values ​​are therefore corrected to a real, but still optimistic value. The basic standard of minimum consumption is 4.5 Wh (watt-hours) per kilometer of assisted riding, as mentioned above, in which the rider is assisted by the electric drive. This standard corresponds to the average consumption when riding, when the electric bike still helps you at least minimally most of the time.

3.Electric assistance technology

Other, although significantly less significant, variations in the bike's range are the result of differences in the control systems used, the efficiency of the motor and the type of battery. Here, it is necessary to mention, for example, the difference in the behavior of assisted pedaling sensors, where there is a difference between frequency (it senses the pedaling speed) and torsion (it senses the torque when pedaling and "doses" the motor's assistance accordingly). In connection with a specific riding style, minor differences in range can be achieved. For example, only light pedaling with minimal force leads to the dosing of more current with a frequency sensor and thus more significant assistance (with a shorter range) than with the same riding style with a torsion sensor. Conversely, choosing a higher gear (smaller wheel), i.e. slower and more intense pedaling, will lead to less strain on the battery with a frequency sensor.

The motor concept (in the middle of the pedaling/in the middle of the wheel) also shows slight differences in range for different riding styles. In the middle of the pedaling drive, there are additional losses in the chain transmission compared to the electric motor in the middle of the wheel, which can be up to 10%. However, the motor mounted in the middle of the pedaling works in a narrower and more favorable speed range than the motor in the middle of the wheel, thanks to the derailleur, which partially compensates for the losses in the gears.

As practice confirms, a slight extension of the range can also be achieved by recuperating the braking force used to recharge the battery in bikes equipped with a recuperation system. However, due to the small momentum of an electric bike and the losses, these are units of percentage and the advantages of recuperation in the case of electric bikes are more of a marketing argument.

E-bike batteries

The first generation of e-bikes were equipped with lead-acid batteries, which were cheap but increased the weight of the e-bike by 10-20kg. The total weight of the bike often approached 40kg, which was one of the main disadvantages given the small capacity and short lifespan of Pb batteries.

Today's standard is lithium-based batteries, originally constructed from lithium-ion cells, later lithium-polymer (better performance/price/safety ratio) and also lithium-iron polymer, which have a higher weight but can handle higher discharge currents.

The lifespan of batteries in e-bikes is indicated in the number of charging cycles, and for lithium batteries it reaches up to 1000 cycles.

What brand of battery cells is the best?

Today, only a few global manufacturers of original cells are established in the world, from which thousands of companies then assemble batteries. The most widely used li-ion cells for e-bikes include Panasonic and Samsung with capacities of 2.6 to 3.5 Ah, in the new Tesla dimensional standard (21x700mm) even over 5.5Ah, LG and Sony cells are also used in e-bikes. Some battery producers of Asian origin also use cheaper, non-branded cells with lower service life and capacity. In the offered lines of branded cells from Samsung, Panasonic, etc., there are always types suitable for e-bikes by their purpose, especially in terms of discharge characteristics, life cycle and shock resistance.

Due to similar parameters, it is not possible to clearly choose which cell is the best. Samsung and Panasonic cells are in a close battle of parameters, with Samsung being more affordable. LG cells have begun to build a reputation in recent years by penetrating the products of several renowned German brands. With Sony cells, it is possible to find types that can withstand higher discharge currents than are normally needed. However, for an electric bike, where the current is limited by the control unit, such a feature is rather irrelevant. The cells then have a higher price and can withstand fewer charging cycles.

To obtain more detailed information about battery properties, we recommend visiting www.baterie-servis.cz

The most frequently asked practical questions about batteries and their lifespan can be found here:

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