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Salt Water Car

Posted: Sat Oct 04, 2014 3:54 pm
by GIThruster
This is a staggering claim. They waited until the end of the pice to give the range, so I was thinking this has a range of maybe 30 miles. Turns out its 373 miles. This is astonishing. I keep waiting for the other shoe to drop. I have to wonder if the system also uses another reactant or catalyst that needs to be purified afterward and so the cost is really not that of salt water. Certainly though, this needs some examination.

http://themindunleashed.org/2014/09/mov ... power.html


Note they followed Elon Musk's lead in putting the technology first into an expensive, limited run car. Just noting, this kind of power density is capable of lifting both fixed wing and rotary aircraft, so there are plenty of other high tech, high cost, early applications for this.

Re: Salt Water Car

Posted: Sat Oct 04, 2014 4:08 pm
by TDPerk
Yeah. Which salt are they using? The Vanadium cell is the only one that I know of that could make this possible, and there's not that much vanadium cheaply available.

I've long thought the aluminum/air cells were cool, but the infrastructure isn't nearly there to quickly replace discharged cells which go to re-manufacture.

Re: Salt Water Car

Posted: Sat Oct 04, 2014 4:19 pm
by choff
How would this differ from an Aluminum Charcoal salt water battery powered electric car, the knock on being the cost of production/recycling of the Aluminum.

Re: Salt Water Car

Posted: Sat Oct 04, 2014 5:58 pm
by D Tibbets
Some up to date (?) information on flow batteries:

http://en.wikipedia.org/wiki/Flow_battery
On the negative side, flow batteries are rather complicated in comparison with standard batteries as they may require pumps, sensors, control units and secondary containment vessels. The energy densities vary considerably but are, in general, rather low compared to portable batteries, such as the Li-ion.

The limitations seem to be the complexity, and weight (?) and the low energy density compared to other batteries. If this has been overcome, it will be interesting, mostly I think due to the possible quick recharge/ fueling possibilities, and that such capability will require a large infrastructure to be developed- a new type of gas station. These gas stations would need tanks to store the reactants and the electrolyte (salt water in this case?) and waste tanks to collect the spent materials for disposal and/ or recycling. This is more involved than simple one tank reactants (gasoline), with atmospheric air serving as the other ingredient and also serving as the disposal medium for the spent/ burned fuel.

And of course, the energy cost of making the reactants is a consideration. If you need to burn coal or other fossel fuel to make the reactants with the associated inefficiencies you are not gaining anything other than local pollution considerations. If you use coal with CO2 sequestration you might claim better enviormental costs, but I'm uncertain. Just like with hydrogen schemes, you are not gaining much, and possibly may be loosing ground- because of the multiple stages, each with it's inefficiencies. Only with cheap, non carbon fossil fuel energy sources* at the beginning of the process are you making real gains. This might include thorium nuclear reactors, or solar/ wind, or obviously practical fusion.

* The stored energy in Carbon fossil fuels are derived from Solar- Sun fusion energy. That it is available as stored hydrocarbons that can easily be collected is the key. Thorium or Uranium are also a stored 'fossil fuel'. It is derived from other older large stars before the Solar system formed. Fusion fuels, depending on the fuels chosen are derived from older stars, or from the Big Bang energy.

Dan Tibbets

Re: Salt Water Car

Posted: Sat Oct 04, 2014 6:10 pm
by RERT
I think the 'Salt Water Car' is more PR than anything else, the website just says this is a flow-battery using 'metallic salts'. It is recharged by taking the used fuel and recharging it off-line.

Worth noting is that the 373 miles is with 2X200 litre fuel tanks, presumably one for fuel and one for spent fuel.

The price of $1.7m is actually quite a bit less than the Bugatti Veyron: I guess that's the opportunity for them, to apply outrageously expensive technology to produce a 'green' supercar!

This will have real impact if there is some kind of dramatic decline curve in the price of the tech. Otherwise it's just good PR for electric cars.

Re: Salt Water Car

Posted: Sat Oct 04, 2014 6:21 pm
by Skipjack
Just chiming in to say that an electric car, even if the power comes from a coal power plant, is still more environmentally friendly than a gasoline powered car.

Re: Salt Water Car

Posted: Sat Oct 04, 2014 6:22 pm
by RERT
RE: D Tibbets

Refuelling a flow battery at a 'gas station' would involve loading an expensive charged chemical, and unloading and expensive uncharged chemical. If you deposit the spent fuel with the gas station, the net cost is the cost of the charging, plus some unknown factor for inefficiency. You don't actually use the chemicals up, at least to first order.

So, limited availability of ingredients for the chemicals might not be an issue. You just need enough for half a tank in every vehicle, which would be, say 300,000,000X200 = 60bn litres in the US, say 60M tons, most of which will be water.

Same comment applies to energy usage to make the chemicals: depends on lifetime/inefficiencies, but is not so huge.

Re: Salt Water Car

Posted: Sun Oct 05, 2014 1:56 am
by kunkmiester
I've heard of a new electrolytic method for refining titanium, they were planning to apply it to vanadium for pilot plants before going for titanium. It could make it as cheap as aluminum though.

Re: Salt Water Car

Posted: Sun Oct 05, 2014 7:13 am
by RERT
Looks like Vanadium is about $25 per kg and global demand a few years back was 61,000 Tonnes.

Re: Salt Water Car

Posted: Sun Oct 05, 2014 12:14 pm
by paperburn1
Once again we are back to the main problem. We do not have the available infrastructure to support such a device. Even something as simple as running a car off natural gas or propane was unable to be done not because of technical ability or feasibility but the fact that we did not have the support infrastructure in place. Even though this battery looks very promising on the outside. The cost of materials the availability of materials, and the cost production will probably limit it from becoming easily available or standard for automakers.

Re: Salt Water Car

Posted: Mon Oct 06, 2014 12:05 am
by Tom Ligon
We got our Prius from Daytona Beach FL to Manassas VA using slightly over one gallon of gasoline last week.

A shame you can't take the AutoTrain to more places.

"Salt Water Car" took my mind back to Hatteras NC and our 1956 Willys Jeep wagon. Hurricane 6 engine (basically six Briggs and Stratton lawn mower engines in one L-head straight block). Been nice if it ran on salt water. On a good day it got 8 mpg. And rusted fast.

Re: Salt Water Car

Posted: Mon Oct 06, 2014 2:42 pm
by GIThruster
paperburn1 wrote:Once again we are back to the main problem. We do not have the available infrastructure to support such a device. Even something as simple as running a car off natural gas or propane was unable to be done not because of technical ability or feasibility but the fact that we did not have the support infrastructure in place. Even though this battery looks very promising on the outside. The cost of materials the availability of materials, and the cost production will probably limit it from becoming easily available or standard for automakers.
Actually it is very common to have cars run off methane or propane. Trouble is though, the lack of infrastructure limits them to local use. Local public works vehicles that never leave their municipality, as well as some taxis use methane. We looked at this as a fleet solution back in the late 70's, but our fleet was passing through the tunnels into NYC and they don't allow bottled gas in the tunnels.

Point is, this is not a new solution, but it is a continuing problem--infrastructure--and tis is why I am always reminding folks that think they have an economical launch solution that if it requires $10B investment into infrastructure, it does not matter how efficient it is to launch with such a solution, as it will never be built.

Re: Salt Water Car

Posted: Tue Oct 07, 2014 6:33 pm
by Asterix
It's worth noting that the much-trumpeted 0-60 number is largely due to the large supercapacitor bank, not the flow cell output itself. It's also that capacitor bank that contributes to the high price of the car.

Re: Salt Water Car

Posted: Wed Oct 08, 2014 9:41 am
by RERT
[oops. VFB seems to need 2 different electrolytes, so I'll modify my guess on the 2X200L tanks to one for each!]

Speaking of infrastructure for this, it isn't clear whether spent fuel can be turned into unspent (charged) fuel simply enough that you might be able to have a fuel re-former on-board which plugs into the mains. Or keep a second tank at home to charge off your solar panels and fill you up quickly once a week. The infrastructure issue may be little different to that for EVs.

Speaking of supercapacitors, I see new abstracts every day which discuss enhanced energy density supercaps. The current highest claims are about 10X commercial. I would be very surprised if supercapacitor energy densities didn't rise rapidly over the next 10 years. Power density is another issue, but is currently huge. Of course, if costs don't fall it will all be for nought, but unfortunately not much is said explicitly about that.

Re: Salt Water Car

Posted: Wed Oct 08, 2014 4:23 pm
by Tom Ligon
"Supercap" may suggest limited thinking. The problem is affordable rapid charge/discharge energy storage with sufficient capacity. Conventional thinking is to use electrochemical cells and ultra-efficient charge storage devices. But when you need a huge increase in capacity or decrease in cost, maybe the smart money is something with radically different physics.

If I knew what, I'd be rich. I'm counting on some high school science student to show up at a science fair with it.

Room temperature superconductor storage? Some bizarre spin physics? Molecular springs? Pumping energy into the vacuum? This business of flow batteries is a departure from conventional thinking, although a somewhat old departure.