Electric car with massive range in demo by Phinergy, Alcoa • Hacker News Board

Re: Electric car with massive range in demo by Phinergy, Alcoa

#41

Post by marvin » Wed, Jun 04, 2014, 10:26 PM UTC

I hate being a naysayer - this is cool technology - but the energy economics won't work out for metal-air batteries if they're used as the main power source. Recharging a metal-air battery is grossly inefficient, and a big part of the advantage with electric cars is that they use less energy in every step of the process except initial manufacturing. This means that the general economics of metal-air batteries will not work out either, because the system requires a physical supply chain that is much more expensive to build out than the electricity distribution network that already exists. Add to this that range anxiety is for the most part eliminated with >60kWh electric vehicles, and this is a no-starter.

Where metal-air batteries could have a place, is as a trickle charging device that will be replaced only rarely, perhaps during an annual checkup, and used as a backup only on the few occasions where fast charging is unavailable or unwanted. But battery vehicle companies are onto this idea already - the Tesla Model S has space for what some suspect is in fact an upgrade slot where a metal-air trickle charging battery can be installed.

The problem is, most mainstream news articles writing about progress in battery-electric vehicles are already far behind the state of the art. Tesla's innovation and execution in this space has largely removed range anxiety for all but a small (<5%) number of trips, and already have a very strong quick charging presence in multiple countries. The future is electric and is already here - most people just haven't noticed.

Re: Electric car with massive range in demo by Phinergy, Alcoa

#42

Post by abat » Wed, Jun 04, 2014, 10:28 PM UTC

scythe wrote: post #23

So I've posted this before, but aluminum smelting is just plain old too hard for this to be as cheap as batteries. I mean, it's great if you're Alcoa, an aluminium smelter, but let's take a look at bulk prices: Aluminium costs $1.80/kg: http://www.indexmundi.com/commodities/?commodity=aluminum Alumina, the product of the aluminium-air reaction, costs ~$0.45/kg: http://www.indexmundi.com/en/commodities/minerals/bauxit…

The idea is it's a backup battery instead of a backup gasoline engine. Being "nearly as expensive as gasoline" could still be a win because it could be used in electric vehicles without having to add a backup generator engine. Also it could have other benefits like being safer (less combustible), producing fewer emissions on the road, and weighing less than gas.

That said, I'm not saying I'm believer in this tech

Re: Electric car with massive range in demo by Phinergy, Alcoa

#43

Post by trhway » Wed, Jun 04, 2014, 10:30 PM UTC

nardi wrote: post #35

trhway wrote: post #9

metal-air batteries (fuel cells), rechargeable and not, is the future. Having comparable to gasoline energy density, yet higher efficiency - 60-90% vs. 30% of gasoline, it will transform cars and especially planes (subsonic ones). You can imagine that it is absolutely not an issue to replace a 100Kg spent aluminum fuel cell block on a small plane at airport. It would also be better than gas turbine for bigger commerc…

But what's the efficiency of the Hall–Héroult process? [1] [1] http://en.wikipedia.org/wiki/Hall-Héroult_process

my bet actually is on potassium-air. The known and projected configurations of such batteries would most probably contain organic/aprotic electrolyte, so it is pretty nasty/flammable inside, yet they are rechargeable and availability and cost of components and efficiency seems to beat other commodity materials based schemas.

Re: Electric car with massive range in demo by Phinergy, Alcoa

#44

Post by marvin » Wed, Jun 04, 2014, 10:30 PM UTC

jff wrote: post #32

dojomouse wrote: post #13

Earlier quoted context omitted.

It's highly recyclable. Aluminium oxide (the result of the reaction in the battery) is one of the feedstocks for industrial aluminium smelting. Recyclable isn't necessarily the same as 'efficient' or 'a good idea' though. It's energy intensive (haven't checked the efficiency of 'recharging'), and additionally has, as a byproduct, massive amounts of CO2 even before considering CO2 emitted in generating the electricity…

This particular smelter uses hydroelectric power, mentioned in the article.

Moot point, unfortunately. Hydropower displaces fossil energy if the nearby energy markets are halfway deregulated and efficient.

Re: Electric car with massive range in demo by Phinergy, Alcoa

#45

Post by trhway » Wed, Jun 04, 2014, 10:34 PM UTC

scythe wrote: post #23

So I've posted this before, but aluminum smelting is just plain old too hard for this to be as cheap as batteries. I mean, it's great if you're Alcoa, an aluminium smelter, but let's take a look at bulk prices: Aluminium costs $1.80/kg: http://www.indexmundi.com/commodities/?commodity=aluminum Alumina, the product of the aluminium-air reaction, costs ~$0.45/kg: http://www.indexmundi.com/en/commodities/minerals/bauxit…

>The cost of a 3000km battery with 100kg of aluminum is therefore $135, or roughly 44 cents per kilometer, or 70 cents per mile.

$135 / 3000km = $0.04 , not $0.44

That is the beauty of metal "burning" in fuel cells instead of gasoline - gasoline is expensive because it is too little of oil on our planet compare to any common metal.

Re: Electric car with massive range in demo by Phinergy, Alcoa

#46

Post by greglindahl » Wed, Jun 04, 2014, 10:38 PM UTC

marvin wrote: post #41

I hate being a naysayer - this is cool technology - but the energy economics won't work out for metal-air batteries if they're used as the main power source. Recharging a metal-air battery is grossly inefficient, and a big part of the advantage with electric cars is that they use less energy in every step of the process except initial manufacturing. This means that the general economics of metal-air batteries will no…

Huh, the article addresses this issue pretty directly -- did you read it?

  Because the car would still rely on its regular
  rechargable lithium-ion battery most of the time and
  would switch to the aluminum-air battery as a backup only
  if the lithium-ion battery ran out, and because most car 
  trips are 50 kilometres or less, Alcoa estimates the 
  aluminum-air batteries would only need to be changed 
  about once a year.

Re: Electric car with massive range in demo by Phinergy, Alcoa

#47

Post by akouts » Wed, Jun 04, 2014, 10:39 PM UTC

I worked at a large automotive manufacturer in near Detroit a number of years ago when they were considering whether or not to design and manufacture an electric vehicle. The had engaged in full "well to wheels" analysis of potential designs as well as that of competitors and concluded that the energy economics never made sense. That analysis considered how "carbon expensive" it is to spin up manufacturing, manufacture, service and operate a vehicle going all the way back to raw materials sourcing. They felt more optimistic about diesel hybrids but also chose not to pursue that. I find it unfortunate that we don't see a more standardized process for conducting full "well to wheels" analysis that takes into account the full life cycle of a designs, manufacturing and product lifecycle. Would be awesome if a consumer watchdog group existed that had the access and technical competence needed to audit these technologies.

Re: Electric car with massive range in demo by Phinergy, Alcoa

#48

Post by trhway » Wed, Jun 04, 2014, 10:42 PM UTC

stcredzero wrote: post #30

scythe wrote: post #23

So I've posted this before, but aluminum smelting is just plain old too hard for this to be as cheap as batteries. I mean, it's great if you're Alcoa, an aluminium smelter, but let's take a look at bulk prices: Aluminium costs $1.80/kg: http://www.indexmundi.com/commodities/?commodity=aluminum Alumina, the product of the aluminium-air reaction, costs ~$0.45/kg: http://www.indexmundi.com/en/commodities/minerals/bauxit…

Aluminium is not going to get any easier, barring massive breakthroughs in fusion energy and/or the Second Coming. How about vast solar thermal plants in the Sahara?

that would lead to even better thing - silicon-air cells :)

Re: Electric car with massive range in demo by Phinergy, Alcoa

#49

Post by trhway » Wed, Jun 04, 2014, 10:44 PM UTC

pjc50 wrote: post #37

rpedela wrote: post #19

Earlier quoted context omitted.

Something that requires 1,221 F (660.3 C) doesn't seem like something you would want to sit on or pump without serious protection.

Slurry, not molten. This (aluminium powder suspended in a liquid) was considered as a rocket fuel at one point.

Russian super-sonic solid fuel anti-ship missiles burn aluminum based fuel in their ramjet engines :)

Re: Electric car with massive range in demo by Phinergy, Alcoa

#50

Post by lotsofmangos » Wed, Jun 04, 2014, 10:49 PM UTC

abalone wrote: post #39

Doesn't aluminum smelting use crazy amounts of electricity and emit significant greenhouse gases? So not only would we be doing that, we'd also have to ship these 220 lb modules back to the smelters every 1,000 miles? Is there anybody advocating for this besides aluminum smelters?

Read article. The smelter they are using is hydroelectric and the 1000 miles air battery range is only used on long journeys as mostly the car runs on lithium.