Electric Bicycle - History

History

In the 1890s, electric bicycles were documented within various U.S. patents. For example, on 31 December 1895, Ogden Bolton Jr. was granted U.S. Patent 552,271 for a battery-powered bicycle with “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 (A) from a 10-volt battery.

Two years later, in 1897, Hosea W. Libbey of Boston invented an electric bicycle (U.S. Patent 596,272) that was propelled by a “double electric motor.” The motor was designed within the hub of the crankset axle. This model was later re-invented and imitated in the late 1990s by Giant Lafree electric bicycles.

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. Also, the 1899 U.S. Patent 627,066 by John Schnepf depicted a rear wheel friction “roller-wheel” style drive electric bicycle. Schnepf's invention was later re-examined and expanded in 1969 by G.A. Wood Jr. with his U.S. Patent 3,431,994. Wood’s device used 4 fractional horsepower motors; connected through a series of gears.

Torque sensors and power controls were developed in the late 1990s. For example, Takada Yutky of Japan filed a patent in 1997 for such a device. In 1992 Vector Services Limited offered and sold an electric bicycle dubbed Zike. The bicycle included Nickel-cadmium batteries that were built into a frame member and included an 850 g permanent-magnet motor. Despite the Zike, in 1992 hardly any commercial electric bicycles were available.

Production grew from 1993 to 2004 by an estimated 35%. By contrast, according to Gardner, in 1995 regular bicycle production decreased from its peak 107 million units.

Some of the less expensive electric bicycles used bulky lead acid batteries, whereas newer models generally used NiMH, NiCd and/or Li-ion batteries which offered lighter, denser capacity batteries. Performance varied; however, in general there was an increase in range and speed.

By 2001 the terms E-Bike, power bike, pedelec, assisted bicycle, and power-assisted bicycle were commonly used to refer to electric bicycles. The terms Electric Motorbike or E-Motorbike refer to more powerful models that attain up to 80 km/h (50 mph).

In a parallel hybrid motorized bicycle, such as the aforementioned 1897 invention by Hosea W. Libbey, human and motor inputs are mechanically coupled either in the bottom bracket, the rear or the front wheel, whereas in a (mechanical) series hybrid cycle, the human and motor inputs are coupled through differential gearing. In an (electronic) series hybrid cycle, human power is converted into electricity and is fed directly into the motor and mostly additional electricity is supplied from a battery.

The term "pedelec" generally refers to an electric bicycle that incorporates a torque and/or speed sensor with a power controller that delivers assist only when the rider pedals. On the opposite side, a Noped is a term used by the Ministry of Transportation of Ontario for similar type vehicles which do not have pedals or in which the pedals have been removed from their motorized bicycle. Finally, Assist Bicycle is the technical term for such a vehicle and Power-Assisted Bicycle is used in the Canadian Federal Legislation, but is carefully defined to only apply to electric motor assist, and specifically excludes internal combustion engines (though this is not the case in the United States).

Today, China is the world's leading producer of electric bicycles. According to the data of the China Bicycle Association, a government-chartered industry group, in 2004 China's manufacturers sold 7.5 million electric bicycles nationwide, which was almost twice the year 2003 sales; domestic sales reached 10 million in 2005, and 16 to 18 million in 2006. By 2007, electric bicycles were thought to make up 10 to 20 percent of all two-wheeled vehicles on the streets of many major cities. A typical unit requires 8 hours to charge the battery, which provides the range of 25 to 30 miles (40 to 48 km), at the speed of around 20 km/h.