How Big of an E-Bike Battery Do You Really Need?

Written by: Rémy Rossi | April 7, 2025 | Time to read 7 min

Is bigger always better? Learn about what you really need from an e-Bike battery for a great ride.

When choosing an electric bike, considering the battery size is crucial in determining how well it aligns with your intended use and range requirements. Choosing the right battery size is critical for maximizing the range and ensuring optimal performance.

For example, if you have an electric bike battery with a voltage rating of 48V and an ampere-hours rating of 10Ah, the battery’s capacity is Wh = 48V × 10Ah = 480 watt-hours. The typical battery size for electric bikes is somewhere between 300 Wh and 750 Wh. Long-range e-Bikes can have batteries exceeding 750 Wh. For casual commutes and city rides, a battery capacity ranging from 300 Wh to 500 Wh is sufficient.

Extremely hot and cold temperatures can also affect battery performance and range. In cold weather, the chemical reactions inside the battery slow down, resulting in a decreased capacity and reduced range. But for winter riders, there are several ways to maximize e-Bike battery range in cold weather. In contrast, extremely high temperatures can cause the battery to degrade faster, leading to a shorter lifespan.

It’s a good idea to store your electric bike in a cool, dry place that’s away from extreme temperatures. Avoid leaving the bike exposed to harsh weather conditions, as this can negatively impact the battery's performance and overall health. If you plan to store your e-Bike for an extended period, remove the battery and store it separately in a more moderate environment.

If you rely on the higher pedal assist levels and prefer a more powerful ride, you’ll need a higher capacity battery to get the most mileage out of your ride. Riding via throttle mode or the faster assist levels will draw more power from the battery, draining energy faster.

Opt for a larger battery if you often ride in hilly areas. Riding uphill draws more power from the motor, which can drain the battery quickly. For longer and more intense rides, such as off-road adventures or hilly terrain, I recommend electric bikes with battery capacities of 500 Wh to 750 Wh. Electric mountain bike models often have larger batteries to keep up with the larger energy demands.

Heavier riders put more strain on the motor, which consumes additional energy. A larger battery can accommodate the extra power needed to support your weight. And if you frequently carry heavy loads, consider a larger battery size to ensure your electric cargo bike has sufficient power to transport the additional weight without a significant reduction in range.

Most e-Bike models come with a battery included as part of the system, so you need to choose an electric bike that offers the battery size you need. You can’t specifically choose the size of battery for any model, but keep the battery capacity in mind when comparing models that might suit your needs.

When shopping for an e-Bike, consider the following:

For flat terrain and light riders: A 200 Wh to 300 Wh battery capacity may be sufficient if you ride on flat terrain and are a lightweight rider. This range is typically found on lightweight e-Bikes, performance road e-Bikes, and sleek hybrids.

For hilly terrain or heavier payloads: If you frequently encounter hilly or demanding terrain or are a heavier rider, opt for higher battery capacity. This ensures you have enough power to tackle the inclines. Larger batteries may lead to a bulkier downtube or external mounting inside the frame or on the rear rack.

For long-distance riding: Lean toward higher capacity batteries if you plan to go on especially long rides. There are even some models that come with two batteries or the option to install a smaller secondary battery, often called a “range extender” that fits in a bottle cage.

How long does it take to charge an electric bike? On average, charging an electric bike with a standard charger from empty to full can take 2 to 6 hours. However, keep in mind that this can vary based on the following factors:

Battery capacity: Bigger batteries take longer to charge. Higher-capacity batteries, such as 500 Wh or 600 Wh, will generally take longer to charge than smaller batteries.

Charger speed: Chargers with a higher amp rating provide faster charging. Some bikes have optional faster chargers for quicker battery replenishment, reducing full charging time. For example, Giant e-Bikes come with the brand’s fast (4-amp) or smart (6-amp) chargers for optimal charging.

Battery health: As batteries age, their charging speed may decrease as overall capacity also falls. Regular maintenance and care can help maintain battery health and charging efficiency.

To get a more accurate estimate for your specific electric bike, refer to the manufacturer’s guidelines and specifications, as they will often provide information about charging times based on the battery capacity and charger provided with the bike.

At Upway, we offer a wide selection of high-quality used electric bikes for every budget. Our skilled technicians thoroughly review, test, and certify each bike to ensure it meets our rigorous standards.

Whether you’re searching for a basic commuter bike or a versatile electric cargo bike for family outings, Upway has the perfect option. Our range of affordable electric bikes caters to every rider, allowing you to make a conscious choice without breaking the bank.