Battery Powered Tram Charges in 60 Seconds

SK writes to tell us that a new streetcar, powered by lithium battery, has been invented by the Railway Technical Research Institute in Kokubunji, Tokyo. The new transport is capable of speeds of 40 kph for 15 kilometers and can convert 70 percent of its deceleration energy into electricity which is then sent back to the battery which can recharge in under one minute.

Comments

Re:Correct me if I'm wrong...

[WiglyWorm]

Well, yes and no. Power delivery is not a problem at all. Look at the cable cars in San Fransisco, any modern subway... really most modern rail systems. However, if they can turn 70% of their breaking power in to electrical energy, accelerating the train back up to speed or, apparently, 15Km of crusing can be done absolutely for free. Lowering the carbon footprint to make it more environmentally friendly and cutting costs for the opperator all at once.

How much charge?

[mangu]

"Recharge in under one minute". Sure, but how much charge? Take how many kilowatt-hours of charge you want, multiply it by 60 and you'll get how many kilowatts of power you need to charge it in a minute. Now divide by the voltage to get the current. How big would the cable and the contacts need to be?

It seems we now have the ideal battery (also called a "capacitor"), now let's concentrate on creating the superconducting cables and contacts.

hopefully this time they will stay around

[DMoylan]

The original Drumm train was constructed in the Great Southern Railways workshops at Inchicore. The weight of the train with passengers was about 85 tons. There was seating accommodation for 140 passengers. The train could accelerate from standstill at about 1 m.p.h. per second and attain speeds of 40 to 50 m.p.h. with ease. The train was fitted with a successful system of regenerative braking, whereby an important fraction of the energy surge made available on a down-gradient or on de-accelerating at a station was returned to the battery. The Drumm Battery train operated successfully on the Dublin to Bray section of the line with occasional runs to Greystones some five miles farther on, from 1932 to 1948. As passsenger numbers increased two pairs of power units were joined under the control of one driver and later a specially wired coach was put between the two trains bringing its capacity up to 400 passengers. By 1939, four Drumm trains had been built but it became impossible to secure orders and raw material once the World War 11, 1939-1945, broke out. The Drumm Battery Company folded in 1940. The outbreak of the war made the Drumm trains invaluable as coal for steam engines was in short supply and inferior. With the war over, it was decided in 1949 to scrap the Drumm trains at a time when the promise of diesel locomotives pointed to the end of the steam era. The Drumm trains, minus their batteries were sometimes used as ordinary coaches. http://chem.ch.huji.ac.il/history/drumm.html

Awesome Lithium Tech

[Bryan Ischo]

If its battery is anything like lithium ion batteries used in laptops, then after a year it'll only go 5 km on a charge instead of 15. Also it will do weird things like indicate that it has enough charge to go another 5 km but just suddenly use up its last 20% in under a minute.

I am not a big fan of lithium ion tech. It seems very gimmicky to me; allowing manufacturers to claim that their laptop batteries last N hours when in fact that will only be true for less than 6 months, as the charge capacity of lithium ion batteries always rapidly deteriorate.

My Panasonic Y2 battery started at 6+ hours per charge, and is now, after not even three years, down to about 2.5 hours per charge.

So if the streetcar in question uses similar tech, then I would expect its range to diminish rapidly with recharges. Since it will be recharged much more frequently than any laptop would, can we even expect its battery to last a whole year before becoming basically worthless?