A new full-sized folding bike with a 36 volt Lithium Ion battery pack is available in the U.S. for the first time. Named the EW-475-Li, it was introduced in late March 2011 and is currently on sale at High 5 Scooters. See pictures below:
X-Treme introduced a comparable full-size folding bike with a 24 volt Lithium Ion battery pack in September, 2009, called the XB-310Li which was very well received but it has been out-of-stock on since March of this year and is not expected to be restocked until early June, 2011. The EW-475 has a larger battery pack than the XB-310Li (36 volt and 10 amps vs 24 volt and 8 amps for the XB-310Li) and uses the super-stable extremely long-life LiFePO4 battery chemistry.
The EW-475-Li has 26" wheels, folds in half and comes with folding pedals. It is powered by a state of the art 300 watt hub motor combined with the powerful 36 volt lithium battery. This bike has it all including both front and rear shocks, disc brakes and a lightweight aluminum frame. And it is built with all top of the line components. It weights a lightweight 52 lbs which includes bike, battery and motor.
The EW-475-Li has an independent full twist throttle -- in addition to the regular 'pedal assist' mode. So, you can pedal with a significant boost from the electric motor or not pedal at all. The bike has a top speed of 20 mph* and up to 25 miles per charge using the motor only. There are really three modes operation: (1) You can turn off the power and pedal this bike like any other bicycle; (2) You can turn on the power and receive a strong electric motor assist as you pedal (this is when you'll feel like superman or superwoman!); or (3) You can use the variable-speed twist-throttle the entire time - no pedaling required.
More specifications and pictures can be found at http://www.high5scooters.com/productinfo/ew475.htm