Posted on 12/13/2007 11:42:31 AM PST by Restore
I am thinking of converting a gas supermoto motorcycle to electric for around town. If I wanted a peak HP of 50 (38KW), average output of 12KW for say 1.5 hours, how many of these modules would I need?
This is from another source and for now it looks like Toshiba doesn’t plan on using it for automotive applications.
The only applications mentioned in the press release are electric bikes, electric motorcycles, construction machinery, and fork lifts with future plans for providing batteries for hybrids and full electric cars. Toshiba vice president Toshiharu Watanabe says;
Good grief. I meant to add “in the near future”.
You need to give us the AH rating of the battery...(how many amps the battery will provide at it’s rated voltage)
I think the other major consideration of battery powered vehicles is the cost of the batteries...
It says that one Cell puts out 2.4V and has a nominal capacity of 4.2 AH.
But the Module (10 Cells) gives you 24V, but only, again, 4.2 AH. Can that be correct? Shouldn't it read 24V and 42 AH?
I hope they get it down to the size for my cellphone.
I think the other major consideration of battery powered vehicles is the cost of the batteries...
++++++++++++
and they are hard on the earth. I never undestood why the greenes never mention that.
Do you suppose that means that one could not simply go out and purchase the modules and DIY up a bike or golf cart conversion?
No,because when wiring DC batteries in serial,the voltage increases,but the current stays constant.If you want the current to increase and the voltage to stay the same,you’d wire it in parallel.Ohms Law.V=IxR
So,if you wired in parallel,10 of the batteries,the voltage would stay at 2.5,but the current would increase to 42AH.
If they wire them in parallel, the the voltage stays the same and the amperage goes up by a factor of 10, to 42.
Either way, the energy stored is the same (multiply AH by Volts to get Watt-Hours).
I don't think so -- not if they're in parallel, which is what I believe is necessary to up the voltage through multiple cells.
It doesn’t sound like much of an improvement (if any) in power density, at 150 grams for 4.2 Ah @ 2.4 V. Actually, I think current soft-sided LiPo cells might better them for power density - but they have lousy recharge rates, typically requiring minimum 1 hour to charge, and that’s at a rate that will reduce their lifespan, plus they have a poor shelf life. The power density becomes a little less important when you can recharge so quickly.
24V * 4.2 A/h = 100.8 W/h. If you want 18 kW/h, you’ll need 180 modules.
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No, it’s correct. When the cells are in series you multiply the voltage but in parallel you multiply the amperage. Either way, you still get 10.08 watt-hours of power per cell.
I think it depends on how the cell is wired. If the batteries are in series, then you increase the voltage, in parallel (think jumping a car batt.) you keep the volts the same but increase the amps.
“In Toshiba’s press release, they say that the SCiB Module is 24V, 2000 grams (4.4 lbs.) and is 100x 300 x 45mm. (Read light and small.)
I am thinking of converting a gas supermoto motorcycle to electric for around town. If I wanted a peak HP of 50 (38KW), average output of 12KW for say 1.5 hours, how many of these modules would I need?”
Good question. Good math problem.
Peak power is an issue for Li batteries, but you can pair an Li battery with a supercapacitor to get some ‘instant’ power on acceleration. 12KW for 1.5hr is 18KWh.
Each cell/unit is 2.4V and 4.2 Ah. Watt = Volt*Amps, so is
10.08watts. Not much.
you’d need 1,800 of these to get to 18KWh.
At 150grams, that would weigh 270Kg or 500lbs.
Volume would be 137,826 ccs. or 137 liters.
Still way too heavy and bulky. You could build a car and use it though. 18KWh is about enough for 60 miles range in a car.
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