View Full Version : Only have a 30min SI but still need to charge the scooter?
No prob... Charge the scooter to 80% in 1 minute. :supz:
I can't wait until someone makes the first battery for dive use with these babies...
http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm
DeWayne
03-30-2005, 10:39 AM
Cool deal 8) Did not Guy ? (creator of the monster?) set up his commercial scooter to use Lion batts? Whatever became of that, I have not seen anything on them since talking to him at last year's CDS seminar :?:
Signal 20
03-30-2005, 12:15 PM
No prob... Charge the scooter to 80% in 1 minute. :supz:
I can't wait until someone makes the first battery for dive use with these babies...
http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm
you need a scooter to worry about that in the first place ;-)
curtschu
03-30-2005, 01:00 PM
I notice alot of the lights using NicMetal Hydrid batteries has anyone tried Lithium Polymer batteries? They are used by the model airplane guys in the park fliers, They charge fast are VERY powerful based on weight.
Genesis
03-30-2005, 02:07 PM
Lithium based chemistry batteries have some special problems.
1. If overcharged or shorted they will burst.
2. Lithium + H2O = Hydrogen, Lithium Hydroxide, and Heat - lots of it. In other words (given that there will be an airspace in there originally), BOOM! :lol:
3. If overdischarged they are destroyed - thus, they must have a "hard off" circuit in the pack that prevents that from happening.
These characteristics mean that you need circuitry in each pack so that they charge in parallel but discharge in series - this permits the charger to sense each cell separately, which is necessary to prevent the burst + BOOM problem. You also would get little or no warning before you lost your light (or scooter) when the low charge warning went off on you.
Ever notice how the Lithium Polymer batteries used in phones, laptops and cameras aren't bare cells - they're always packs of some kind? That's why - the circuitry necessary to make them (reasonably) safe by charging in parallel while discharging in series, plus overdischarge protection.
I think the "BOOM" risk could be quite severe - a short in a cannister (or scooter) caused by water intrusion could easily lead to a runaway situation with really bad consequences.
Genesis,
Those are easy enough to fix. Just dont get it wet... :-D
Genesis
03-30-2005, 03:18 PM
Not necessarily.
There have been defective packs in laptops that have caught fire without getting wet. Water vapor in the air is enough.....
Not necessarily.
There have been defective packs in laptops that have caught fire without getting wet. Water vapor in the air is enough.....
Thats not an issue down here... :wink:
curtschu
03-30-2005, 08:07 PM
We do enough crazy already why not add explosives to the mix :twisted:
Great info G I know the model guys take special care charging. Mostly putting them in a pyrex measuring cup but these are single cells I think so they just have circuitry in the charger. I did not see the work Polymer in the article that was posted but I suspect that is probably a Li-Po battery.
normblitch
03-31-2005, 06:55 AM
No prob... Charge the scooter to 80% in 1 minute. :supz:
I can't wait until someone makes the first battery for dive use with these babies...
http://www.toshiba.co.jp/about/press/2005_03/pr2901.htm
Tegg,
Genesis has already made sone great technical points; allow my to put it via some bit more basic and practical notes...
Ahr and WattHr IN must ALWAYS exceed those OUT...while I am not familiar withthe current/voltage specs on today's scooters, what I envision is a charger with, lets say, 4 gauge wire to handle the current (Amps) needed to accomplish such a rapid charge..and just WHAT kind of B+ power supply will this require? I see a Generac on a trailer here...<g>
Cost is going to be another annoyance...Ask any greybeard solder-head what they were paying for NiCads (both wet and dry) as early-adopters...until the batteries you cited (BTW, THANKS for the Link! it is a GREAT read...) and mass-market for Autos and the like, the Cost/AHr is going to be DREADFUL, IMHO.
Now what gets MY attention, is the technology where the battery "sandwich" is formable and can actually be used as the exoskeleton of a vehicle...don't remember the name of this technology, but it is being studied...Genesis?
Norm
curtschu
03-31-2005, 08:05 AM
When did this become the Techno Geek Forum????? :-D Bahh Technology.... :evil: Just kidding guys as Tegg found out this week I'm a Computer Geek too. What is it with Cave Diving it seems to attract Techno junkies? and Cops?
normblitch
03-31-2005, 09:05 AM
When did this become the Techno Geek Forum????? :-D Bahh Technology.... :evil: Just kidding guys as Tegg found out this week I'm a Computer Geek too. What is it with Cave Diving it seems to attract Techno junkies? and Cops?
(Thread now officially Hijacked)
IMHO, this is a natural effect from the needed multi-disiplinary science ed needed by today's tech diver...believe me, the Internet (thus the XPTR Geek) has made the promulgation of Tech info MUCH more full than in the pre-WWW days)...the Law Enforcement angle MAY be an outshoot of Police Divers, or just the legasy of Henry N...
This phenomonon is not limited to Divers...Many Ham Radio ops share Model Railroading and Gun Lust...go figure...
73 de Norm KE4GAH
Genesis
03-31-2005, 11:42 AM
Norm - there is nothing particularly difficult about forming the electrodes/plates in most chemistries that don't use a liquid electrolyte to whatever shape. The cylindrical shape used by most common batteries is a matter of convenience and economy of space (and thus cost, since the case costs money too)
normblitch
03-31-2005, 12:18 PM
Norm - there is nothing particularly difficult about forming the electrodes/plates in most chemistries that don't use a liquid electrolyte to whatever shape. The cylindrical shape used by most common batteries is a matter of convenience and economy of space (and thus cost, since the case costs money too)
(Unless it is the PNO2 talkin')...I could SWEAR I had seen a report (maybe SPACE.com) about a high Watt/Hr density dry/paste electrolyte battery style that had STRONG possibilities for forming...the idea was to use aircraft skin (think of the sq foot of a WING) or the outer shell of a satillite AS the battery...the TRICK is to use a low mass plate, so as NOT to invent a gel-lead acid battery sheathed Dirigible (see also; Led Zepplin)
So sorry, could NOT resist...
Norm
ethan_brodsky
03-31-2005, 06:34 PM
Toshiba's been doing a lot of cool stuff lately. They also have miniature fuel cells:
http://www.toshiba.co.jp/about/press/2005_02/pr2801.htm
100 mW (presumably at 3-5V) out of a 2.2 cm x 5.6 cm x 0.5 cm module. Or, including a 2cc methanol fuel tank good for 20 hours burn time, 2.2 cm x 5.6 cm x 0.9 cm.
Assuming your scooter pulls 10 A @ 24 V, that's 240 W. You'd only need 2400 of these fuel cells, along with a 5 L tank of 99.5% pure methanol, and probably some air too, to make a scooter with 20 hour burn time. The energy storage module would weight approximately 20 kg (50 lbs) and occupy 27 L (1 cubic foot) of space. You might need to run some water through it to keep them cold, but we're only talking about 1kW or so of waste heat, so that's not too much (perhaps you could run it through your suit for added warmth). You'll also need to find a way to get rid of the combustion - that might be the biggest problem underwater. Perhaps a small compressor that pumped them overboard? Would a scooter that bubbled be DIR?
The biggest problem is that these babies probably cost $1000 each right now, and probably will cost $10-100 when they are commercially available.
Then again, we could always just get power from the decomposition of hydrogen peroxide. Then all you would need would be a tank of high-purity hydrogen peroxide, a small pump, a catalyst, and a turbine. You could probably build a scooter that would pull you at 50 knots or more - it works in torpedos.
Just dreaming,
Ethan
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