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Lithium or hydrogen bike? Choose your steed

Sanyo's new eneloop hybrid bicycle recharges while it's being pedaled; Iwatani showed off a fuel cell bike that runs on a hydrogen fuel cell stack.


More and more electric bicycles are being developed in Japan to give riders a little help when commuting or going grocery shopping. They're a common sight on the hilly streets of Tokyo, where "mamachari" bikes with baskets and kid seats over the wheels are the norm.

Sanyo recently unveiled a new series of two-wheel drive eneloop electric hybrid bicycles whose lithium ion batteries can recharge while the bike is being pedaled on level terrain. Previous models relied on braking or downhill energy to re-power.

The Eco Charge Mode featured on the SPL series gives you more recharging opportunities while the bike is in use. It reads foot pressure on the pedals, as well as pedal torque and the revolution speed of the dynamotor on the front wheel, and charges the battery along flat roads, on downhills, and during braking. When the rider comes to an uphill gradient, the motor assist function kicks in automatically.

The Eco Charge Mode increases driving distance per charge by 53 percent compared with just biking in a high power-assist mode; Sanyo says the new SPL bikes can travel about 34 miles per charge.

By traveling 1 kilometer (1,093 yards) on flat ground in Eco Charge Mode, you can generate enough electricity to go about 300 meters (328 yards) in Power Mode, which provides lots of power assist. A power reserve function stores an extra bit of juice for those times when the battery runs out before you arrive at your destination.

To be released in Japan in April, the 26-inch CY-SPL226 and the 24-inch CY-SPL224 will have a price tag of about $1,700.


Meanwhile, industrial products maker Iwatani recently showed off a hydrogen-powered electric bicycle at FC Tokyo, a gathering of companies in the fuel cell business.

Developed last year, the motorized hydrogen bicycle has a 60W polymer electrolyte fuel cell (PEFC) stack, a 26V lithium ion battery, and a hydrogen cartridge that's located in a cargo carrier over the back wheel.


Battery power drives the bike's motor to help with pedaling. When the battery power runs low, the cartridge automatically supplies hydrogen to the fuel cell to recharge the battery, but the system can still provide pedaling assistance during the recharge. It eliminates the need to take out and recharge the battery--much more convenient than charging an e-bike for five hours.

The bicycle weighs about 68 pounds and can provide power-assist travel for about 28 miles, depending on road conditions, or a continuous power supply for three hours.

Iwatani has been showing the bike off at Kansai International Airport and various events like FC Tokyo. It's a great concept, but Iwatani won't be commercializing the bike anytime soon because the PEFC's output is too weak.

"Depending on driving conditions, it sometimes cannot supply the bicycle with enough electricity," the company told Nikkei Monozukuri magazine, adding that it plans to make the PEFC system more powerful.