Power Needs of an Electric Bike

For riders who dream of rolling hills and endless coasting, an electric bike can take the sting out of the inevitable uphill pushes. These bikes use a battery to store electricity to provide a little boost when you need it, giving you the opportunity to extend your cycling commute or daily ride. The power supply for these bikes varies from model to model, but all of them use a battery to store the motor's electric charge.

  1. Pedaling Power

    • The most common type of electric bike is known as a pedelec. A pedelec adds motor assistance to your natural pedaling stroke, adding more or less depending on your cadence and effort. A pedelec's motor is always running when you're pedaling. Other electric bikes use a motor that can be turned on and off at the discretion of the rider using a throttle on the handlebar. Because of motor vehicle restrictions, a throttle-activated electric bike can only activate its motor when the rider is pedaling. Both types of electric bikes usually get about 10 to 20 miles per charge, but this distance can vary depending on how much assistance you provide through pedaling.

    Juiced and Amped

    • The battery used to store the charge of an electric bike usually falls into two categories. The most modern and most common battery type is a lithium ion battery. There are several variations of this type of battery, but their hallmark is a long service life and a great ratio between weight and energy storage. A lighter battery makes for a faster and more convenient bicycle, so these batteries are slowly replacing the second most common battery type, the nickel metal hydride battery, or NiMH. A NiMH battery has a predictable life and is well-proven, since it's the type found in most cars. Lithium ion batteries generally get between 700 to 1000 recharge cycles before they are spent. In comparison, NiMH batteries get around 500 to 700 charges.

    What A Charge

    • Electric bikes use an electric charger that plugs into your home's outlets to recharge the battery. It is extremely dangerous to use any charger other than the one that comes with your electric bike, since manufacturers charge their batteries at different rates. Usually, a full charge takes between six to 12 hours, depending on the model of electric bike. A regular charge after your commute can take much less, since you might not fully drain the battery. Lithium ion batteries take less time to charge than NiMH batteries, sometimes charging in as few as two to six hours.

    Maximum Power

    • A number of factors can affect the amount of power your battery can supply to your electric bike's motor. Batteries are essentially chemical reactions between a cathode, an anode and a liquid called an electrolyte. This means that especially cold temperatures can slow the rate of reaction, giving you less power when you need it. Storing your bike indoors when it's cold can improve the performance of your battery. With enough charge cycles, your battery will eventually lose capacity or fail completely; expect to replace your battery at some point during its operative life.