Toshiba Corp exhibited a power-assisted bicycle that Cannondale Sports Group LLC manufactured by using a battery module based on Toshiba's quick-charging lithium ion rechargeable battery "SCiB" (See related article).
The bicycle was on display at the 15th World Congress on Intelligent Transport Systems (ITS), an automotive electronics-related event that took place in New York from Nov 16 to 20, 2008.
The SCiB features enhanced safety with the use of lithium titanate for the negative electrode. The battery module exhibited this time is composed of 10 battery cells connected in series. The cell each has an average voltage of 2.4V and a current capacity of 4.2Ah, measures approximately 62 x 95 x 13mm, and weighs about 150g.
The module has an average voltage of 24V, measures approximately 100 x 300 x 45mm, and weighs about 2,000g. The bicycle runs 20-30 miles per charge, according to Toshiba.
Cannondale plans to launch the bicycle in North America and Europe in early 2009. Although the details are not available at this point, it is expected to be priced at about US$3,000. However, the company is unlikely to release the bicycle in Japan at the moment because the current model violates the Japanese Road Traffic Law.
The ratio of the force generated by the rider's legs to the assisting force of the motor in Cannondale's bicycle is 1:2 while running. Meanwhile, the ratio of the leg force to the assisting force must be up to 1:1 under the Japanese Road Traffic Law. In other words, the assisting force from the motor must be within 1/2 the rider's pedaling force.
Correction Notice: Because of a reporting error, we incorrectly described the ratios of the leg force to the assisting force as 1:1 and 2:1 (in the order of appearance), which actually are 1:2 and 1:1. Also, the weight of the battery cell is not 15g but 150g.