Ebike Battery: Everything You Need to Know

While the electric motor is the most vital component of an ebike, the battery is close. Your choice of battery can impact travel range (on a single charge), rider weight, comfort, and – in terms of battery placement – appearance.

Unfortunately, batteries come in various types and capacities, and there’s a lot of terminology to learn, making shopping a headache-inducing experience. Understanding what goes into an ebike battery can help you make an informed purchase.

What is a Battery Pack?

A battery pack, made up of smaller battery cells, is stacked in a specific way to store and deliver electrical power to the motor, propeling the ebike forward. The two most common types of battery packs are lithium-ion and lead acid.

Although lead acid batteries are cheaper and more powerful than lithium-ion, they have a shorter lifespan, take longer to charge, and are prone to combustion, making them less safe. These days, lithium-ion is the go-to standard for electric bikes.

FURTHER READING: Heybike E-bikes Certified with UL 2849 Standard

Electric Bike Batteries Explained

What’s the first step to choosing the best electric bike battery? Read, read, read. Learn as much as you can about what goes into them. This information will help you separate fact from fiction and make an informed choice. If you’re wondering how does a long range ebike work, read on to learn more about the battery.

Watts (W)

Watts is a unit of measurement that determines the amount of energy consumption. It is a combination of volts, which refers to how fast electrons move, and amps, which refers to how many electrons can pass through at once. Multiplying volts by amps gives you the total watts amount. There are two watts ratings: continuous (nominal) and peak. Continuous is the maximum output sustained over a given period, while peak is the max output in a short burst.

The average watts range for an ebike motor is 250w to 1000w. More powerful electric motors can exceed 1000w, but these ebikes fall under a different category where the rider and vehicle must be licensed and registered.

Watts Per Hour (Wh)

Watts per hour is an important metric. It determines how much energy an ebike battery consumes continuously for an hour. It is one of the most accurate, infallible ways to tell how far a battery will go on a single charge. For instance, you can expect a 500wh battery to deliver about 500 watts for 1 hour, 250w for 2 hours, and so forth.

That said, most ebikes don’t deliver the same continuous power for a whole ride, so these figures are still estimates. However, they are close enough without getting too technical. The main takeaway is that, for the most part, the larger the battery capacity, the longer the battery goes on. This travel range, of course, depends on how hard you use the motor.

The average Wh range for an ebike motor is 250Wh to 1000Wh.

Amperes (Amps)

Amperes, or amps, is a unit of measurement that describes the intensity of an electrical current. If voltage refers to how fast electricity travels, then amperes is how powerful the force of that electricity current is. The higher the amp count, the more electrical current (power) an electric bike battery will supply to the motor.
Most ebike manufacturers do not list amp ratings alone but instead list Amps-Hours (Ah).

Amp-Hours (Ah)

As you can probably guess already, Ah measures how many amps a battery can deliver to a motor over an hour. The more amps a battery can transfer per hour, the more power the motor can generate. The result? A faster acceleration and a higher top speed.

The average Ah range for ebike batteries is 12.5Ah to 18Ah. If the battery of an ebike has a 15Ah specific, it can provide 15 amps for one hour or 7.5 amps for two hours.

While this metric is useful, it doesn’t tell the whole story. Many factors influence an ebike’s travel range: riding against the wind, up steep hills, on rough terrain, and with excess weight. All these factors can decrease the motor’s performance, forcing the battery to work harder to maintain the same speed.

Battery Management System (BMS)

All electric bikes have a built-in BMS, or a battery management system, to charge and protect the battery. The BMS monitors the level of charge for each battery cell, managing the charging process to prevent overcharging and limiting the electric flow to stop overheating. Aside from protecting the battery from damage, the BMS also helps prolong battery life.

Follow these charging practices to prolong your ebike battery’s lifespan:

• Re-charging your battery before it fully dies
• Unplugging the charger once done using it
• Only charging when the battery pack is warm or at room temperature (not cold or freezing)

What is the Range of an Ebike Battery?

Want to know how far can electric bikes go on a full charge? You’re in the right place.

Calculating the range of an ebike battery is easy once you know the basics. While your calculation may not be 100% accurate, it can serve as a guide to help you choose a battery that suits your needs. However, you can factor in a few variables – average speed, throttle use, wind – to make your calculation more accurate.

Here is a sample calculation for estimating e-bike battery capacity.

1. Calculate Wh Rating

Remember, this is your watts-per-hour rating. If you don’t have this number, don’t worry. Refer to the manufacturer’s specifications to find both the voltage and amp-hour rating. Let’s say your ebike battery has the following specifications:

• Voltage: 48V
• Amp-hours: 15Ah

With these figures, you then perform the following calculation: 48v x 15Ah = 720Wh.

2. Calculate Miles Range

Next, calculate the number of watt-hours your ebike uses per mile. Now, this part is tricky, as many factors influence this figure. Typically, a 500w ebike riding at about 20mph on mostly flat terrain will use about 25Wh per mile.

From there, perform the following calculation: 720Wh ÷ 25Wh/mi = 28.8 miles range.

3. Consider External Factors

But what if you are riding in more challenging conditions? The Wh/mi count will be higher. Consider factors like increased weight, faster wind speeds, and steeper elevations. Factoring these in will make your calculation more accurate.

Let’s say that during your ride you carry a backpack, ride up steeper hills, and on rougher terrain. Therefore, you need to rely on the throttle and pedal assist more to get where you want to be. As a result, your watt-hours per mile might be 35Wh/mi, so 10 points higher than the previous calculation.

Based on this new information, your calculation would look like this: 720Wh ÷ 35Wh/mi = 20.57 miles range.

Understanding E-Bike Batteries, More Informed Choices

As you can see, there is a lot to consider when you choose a battery of an ebike. Above all, though, what matters is that it fits your needs. For casual ecycling, consider choosing a lighter and smaller battery. Why? Most ebike riders don’t travel further than 20 to 25 miles each day. Therefore, you may never fully utilize the benefits of a higher-capacity battery anyway.

Another thing to keep in mind is the size and weight. The higher capacity the battery, the heavier and larger it will be. That means the battery may be too bulky on your ebike frame, and it may not look very appealing either. You may also have a harder time carrying your ebike up the stairs and placing it on bike racks.

Of course, if you’re an off-roading enthusiast and don’t mind the extra weight, go for a higher-capacity battery. If you want to attach a trolley or bike rack pannier bag, then you may need the extra charge to ride further. Ultimately, be sure to do your research and compare your options until you decide. Explore the full range of Heybike electric bikes to find your ideal ebike today.