An e-bike or electric bicycle"Guide to e-bikes". Association of Cycle Traders. Accessed 1 May 2022. is a type of a motorized bicycle with an integrated electric motor used to assist propulsion. E-bikes, alongside bicycles and e-scooters, are types of micromobility vehicles. E-bikes are a quick and reliable method of transportation, a fun type of recreation, and also an adaptive technology for weaker, older, disabled, or inexperienced riders. An e-bike's electric motor helps riders cover greater distances and steeper hills without the need for high physical effort. E-bikes are sold in a large number of different form factors for different use cases and sporting purposes. E-bikes are generally not suitable for long-distance cycling as the battery usually lasts to per charge, depending on the power level used.
E-bikes generally fall into two broad categories: bikes that require the rider's pedal-power (i.e. pedelecs) and bikes that control the motor with a throttle such as a twistgrip, integrating moped-style functionality. Both retain the ability to be pedaled by the rider unlike electric motorcycles and e-scooters. E-bikes use rechargeable batteries and are typically motor-powered up to , some to .
In many places, e-bikes (especially pedelecs) are legally classified as bicycles rather than mopeds or motorcycles. This exempts them from more stringent laws regarding their certification and operation, such as licensing and mandatory safety equipment. E-bikes can also be defined separately and treated under distinct electric bicycle laws.
History
1890s
In the 1890s, electric bicycles were documented within various U.S. patents. For example, on 31 December 1895, Ogden Bolton Jr. was granted a patent for a battery-powered bicycle with a "6-pole brush-and-commutator direct current (DC) hub motor mounted in the rear wheel" (). There were no gears and the motor could draw up to 100 amperes from a 10-volt battery.
Two years later, in 1897, Hosea W. Libbey of Boston invented an electric bicycle () that was propelled by a "double electric motor". The motor was designed within the hub of the crankset axle, and use of the battery could be split depending on flat or inclined road use.
By 1898, a rear-wheel drive electric bicycle, which used a driving belt along the outside edge of the wheel, was patented by Mathew J. Steffens. An 1899 patent by John Schnepf () depicted an electric bicycle with a rear-wheel friction, "roller-wheel"-style drive.
1960s In 1969, Schnepf's invention was expanded by G.A. Wood Jr. (). Wood's device used four fractional horsepower motors connected through a series of gears.
Hub motors fell out of favor until around 2015 when they made a resurgence on inexpensive electric bikes.
1990s to present day
From 1992, Vector Services Limited offered the Zike e-bike. The bicycle included nickel–cadmium battery (NiCad) batteries that were built into a frame member and included an permanent-magnet motor.
Torque sensors and power controls were developed during the late 1990s. For example, a Japanese patent (6163148) was granted in 1997 to a team led by Yutaka Takada, for a "Sensor, drive force auxiliary device ... and torque sensor zero point adjusting mechanism".
American car executive Lee Iacocca founded EV Global Motors in 1997, a company that produced an electric bicycle model named E-bike SX, and it was one of the early efforts to popularize e-bikes in the US.
By 2007, e-bikes were thought to make up 10 to 20 percent of all two-wheeled vehicles on the streets of many major Chinese cities. A typical unit then required eight hours to charge the battery, which provides the range of , at the speed of around .
In the 2010s e-bikes attracted considerable traction in Europe led by government policies and environmental awareness encouraging sustainable technologies. Some countries such as Germany and Netherlands turned into significant e-bikes markets with the aim to reduce urban congestion and carbon emissions. Moreover, the evolution of lithium-ion battery (Li-ion) technology contributed to e-bikes adoption. They provided faster charging times, lighter weight and longer range in order to make e-bikes more efficient and practical for daily use. Additional advancements in hydroformed aluminum alloys and carbon fiber allowed manufacturers to reduce weight while maintaining frame strength. Bikes released in the 2020s featured improved microcontrollers with smoothed power delivery, torque sensors and brushless dc motors.
Definition and classes + E-Bike classes used in most US statesDefined in model legislation authored by the trade group People for Bikes: Model Electric Bicycle Law with Classes. Map of states using model legislation: Overview of Electric Bike Regulations Dimension / Attribute Class 1 Class 2 Class 3 Assist type Pedal only Throttle (optional pedal-assist) Pedal only (some allow throttle to 20 mph) Max assisted speed 20 mph 20 mph 28 mph Max throttle speed N/A 20 mph N/A (or 20 mph cap) Max motor wattage 750W 750W 750W Motor engagement Requires pedaling Propels without pedaling Requires pedaling Integrated speedometer Optional Optional Mandatory Typical minimum age None None 16 years old Helmet requirement Standard bike laws Standard bike laws Mandatory for all riders Paved bike path access Generally permitted Allowed; sometimes restricted Often restricted to roads/lanes Mountain bike trail access Allowed on multi-use trails Mostly restricted Prohibited on non-motorized trails
In the United States, many jurisdictions allow e-bikes up to "Class 3" to be operated without license.
many countries do not have quality standards for e-bikes, rules about who can ride them and where, or even a clear legal definition of what they are.
E-bikes are classed according to the power that their electric motor can deliver and the way the power is controlled by the rider. Bikes with highly powerful electric motors are considered to be mopeds or motorcycles in some areas. The classification of these e-bikes varies greatly, even across local jurisdictions.
The classification of e-bikes is sometimes decided by whether the e-bike's motor assists the rider using a pedal-assist system or by a power-on-demand one. Definitions of these are as follows: With pedal-assist, the electric motor is regulated by pedaling. The motor augments the efforts of the rider when they are pedaling. These e-bikes – called pedelecs – have a sensor to detect the pedaling speed, the pedaling force, or both. With power-on-demand, the motor is activated by a throttle, usually handlebar-mounted, more closely resembling motorcycles or scooters than the original pedal bicycle.
Pedelecs
The term "pedelec" (from pedal electric cycle) refers to an e-bike with mandatory pedalling, a relatively low-powered electric motor and a limited top speed using the motor. Pedelecs are legally classed as bicycles rather than low-powered motorcycles or mopeds.
The most influential definition of pedelecs comes from the EU. EU directive for motor vehicles EN15194 considers a bicycle to be a pedelec if: The motorized assistance over a speed of only engages when the rider is pedalling, The motor cuts out once is reached, and The motor produces maximum continuous rated power of not more than (the motor can produce more power for short periods, such as when accelerating or climbing a steep hill). An e-bike conforming to these conditions is considered to be a pedelec in the EU and is legally classed as a bicycle. The EN15194 standard is valid across the whole of the EU and has been adopted by some non-EU nations including the UK, and the state of Victoria in Australia.
Pedelecs are used much like conventional bicycles yet increase average speeds, especially when the rider is climbing or struggling against a headwind. Pedelecs therefore expand the areas and groups capable of regular cycling, making them popular for bicycle commuters, older riders, younger riders, and those with disabilities.
S-Pedelecs More powerful pedelecs are sometimes dubbed S-Pedelecs (short for Speed-Pedelecs). These have a motor more powerful than and less limited, or unlimited, pedal-assist, i.e. the motor does not stop assisting the rider once has been reached. S-Pedelec class e-bikes are therefore sometimes classified as mopeds or motorcycles rather than as bicycles. In Switzerland the motor power is limited to , the speed without pedalling to and under motor to . In the United States, many states have adopted S-Pedelecs into the Class 3 category, limited to of power and speed. In Europe they are likely to be classed as mopeds, requiring a registration plate and a licensed rider. In Australia, they can only be used on private property.
Power-on-demand Some e-bikes have an electric motor that operates using power-on-demand; the motor is engaged and operated manually using a throttle, controlled usually with a handgrip as on a motorbike or scooter.
With power-on-demand e-bikes the rider can: ride by pedal power alone, i.e. fully human-powered. ride by electric motor alone by operating the throttle manually. ride using both together at the same time. use instead a pedelec controller, if this is fitted.
Some power-on-demand only e-bikes are very different from, and are often not classified as, bicycles. For example, the Noped is a term used by the Ministry of Transportation of Ontario for e-bikes which are not fitted with pedals.
Popularity
E-bike usage worldwide has experienced rapid growth since 1998 as the technology matured and got more affordable. China is the world's leading producer of e-bikes. According to the data of the China Bicycle Association, a government-chartered industry group, in 2004 China's manufacturers sold 7.5 million e-bikes nationwide."China's Cyclists Take Charge", By Peter Fairley. IEEE Spectrum, June 2005 domestic sales reached 10 million in 2005, and around 17 million in 2006."Cheap and green, electric bikes are the rage in China" , by Tim Johnson. Originally published 23 May 2007 by McClatchy Newspapers. In 2016, approximately 210 million electric bikes were used daily in China.
According to trade umbrella body CONEBI, electric bike sales in the EU were over 5 million in 2021, up from 2 million in 2016,Black, Forbes. "The State of the Electric Bicycle Market", Electricbikereport.com, 19 September 2016 700,000 in 2010 and 200,000 in 2007. In 2019, the EU implemented a 79.3% protective tariff on imported Chinese e-bikes to protect EU producers. In 2022, electric bikes continued to grow market share in the EU, rising to 57% of bike sales in the Netherlands, 49% in Austria, 48% in Germany and 47% in Belgium.
In Australia e-bike usage significantly increased through the first half of the 2020s, especially in major cities.
Motors and drivetrains
DC motors are commonly used in electric bicycles, either brushed or brushless. Many configurations are available, varying in cost and complexity; direct-drive and geared motor units are both used. An electric power-assist system may be added to almost any pedal cycle using chain drive, belt drive, hub motors or friction drive.
Brushless hub motors are the most common in modern designs. The motor is built into the wheel hub itself, while the stator is fixed solidly to the axle, and the magnets are attached to and rotate with the wheel. The bicycle wheel hub is the motor. The power levels of motors used are influenced by available legal categories and are often, but not always limited to under . Hub motors are usually located in the rear wheel only but front hub and dual motor bikes also exist. Hub motors were common in 19th century electric bicycle designs but fell out of favor until their resurgence in the 2010s. The hub-motor design is more common among more affordable and less-established e-bike brands. Hub motors are also common for conversion kits and speed-focused custom builds.