Group Demonstrates 3,000 Km Electric Car Battery 363
Jabrwock (985861) writes 'One of the biggest limitations on lithium battery-powered electric cars has been their range. Last year Israeli-based Phinergy introduced an "aluminum-air" battery. Today, partnering with Alcoa Canada, they announced a demo of the battery, which is charged up at Alcoa's aluminum smelter in Quebec. The plant uses hydro-electric power to charge up the battery, which would then need a tap-water refill every few months, and a swap (ideally at a local dealership) every 3,000km, since it cannot be recharged as simply as Lithium. The battery is meant to boost the range of standard electric cars, which would still use the Lithium batteries for short-range trips. The battery would add about 100 kg to an existing Tesla car's battery weight.'
Re:haha. they call if "charging the battery" (Score:4, Interesting)
Battery trailers make more sense than swapping, IMO.
It's a real issue. (Score:5, Interesting)
I have an antique electric tractor. [wikipedia.org] It's 41 years old and runs great, with almost zero maintenance; it uses about 20 cents worth of electricity to mow an acre of grass. If I replace the motor brushes every 30 years, and periodically wash out and maintain the corrosion-prone battery compartment, it will last forever.
But the achilles heel of these machines is battery maintenance, which consists of watering the big lead acid batteries and properly charging them. There are no mysteries in this process, and no great difficulties - you just have to remember to do it, and the batteries simply will not forgive forgetfulness. Properly cared for batteries can easily last twelve years, but it's very common for people to ruin a $600+ set of batteries in two years or less, simply from a lack of mindfulness. That changes the economics of it, which are heavily front-loaded. If your batteries last ten years, the tractor is much cheaper to own and operate than a gasser, but if you destroy your pack in two years, you waste that huge upfront battery investment and take a financial beating.
The Toyota Prius's NiMH battery packs were designed with this human reality in mind; the intelligent battery management electronics are the key to that car's success. Tesla took it one step further; they not only have intelligent battery management that does not require functioning user brain cells, they also built a high cell count charging system that allows rapid charging without compromising battery capacities.
Depending on humans to do battery maintenance doesn't work, in practice, except in the case of engineering geeks who are not even slightly behaviorally representative of the species as a whole.
Read the Article! (Score:5, Interesting)
When I worked in one inner suburb of a medium-sized city, and lived in another, I commuted about 50km each way, 100km in total, and hence 3000km over the course of a little over a month.
I know it is Slashdot and the summary is misleading about it "adding 100kg over a Tesla battery" but if you actually read the article you would learn that the idea is not to replace the existing Li-ion battery but to have this as well as a reserve. As you point out most people only drive short trips for which a Li-ion battery is well suited. This is just to provide a power for long distance driving.
However, depending on the cost, since this battery is only 100 kg and the current Tesla battery is 500kg you could imagine completely replacing the Li-ion battery with five of these and having a 15,000 km range which would probably do most people for the best part of a year. This would only work if it is cheap to replace compared to the cost of a Li-ion battery which lasts for 100,000 km and costs $30k. So assuming the cost of electricity to recharge the Li-ion palances with the installation costs of the multiple aluminium battery packs you would require, the cost per aluminium battery would need to be $900. The cost of 100 kg of aluminium (which seems to be the principle component) is $180 for 100 kg so this does not rule out such a price.
Sadly the killer for this, and all electric cars, is that assuming an internal combustion car uses 6l/100km of petrol the price of petrol would need to reach $5/litre before it became more expensive than the cost of battery or about a factor 4 higher than it currently is in Canada. Still give it a few more years of declining battery costs and increasing oil prices and we will finally be there!
Re:haha. they call if "charging the battery" (Score:5, Interesting)
Bauxite, an aluminium ore, is the world's main source of aluminium. It consists mostly of the minerals gibbsite Al(OH)3, boehmite γ-AlO(OH) and diaspore α-AlO(OH), mixed with the two iron oxides goethite and haematite, the clay mineral kaolinite and small amounts of anatase TiO2.
Approximately 70% to 80% of the world's dry bauxite production is processed first into alumina, and then into aluminium by electrolysis as of 2010
Usually, bauxite ore is heated in a pressure vessel along with a sodium hydroxide solution at a temperature of 150 to 200 C. At these temperatures, the aluminium is dissolved as an aluminate (the Bayer process). After separation of ferruginous residue (red mud) by filtering, pure gibbsite is precipitated when the liquid is cooled, and then seeded with fine-grained aluminium hydroxide. The gibbsite is usually converted into aluminium oxide, Al2O3, by heating. This mineral is dissolved at a temperature of about 960 C in molten cryolite. Next, this molten substance can yield metallic aluminium by passing an electric current through it in the process of electrolysis, which is called the Hall-Heroult process
Re:haha. they call if "charging the battery" (Score:5, Interesting)
Smelting aluminum has actually gotten pretty efficient - despite the ore being relatively cheap there was a time it was more valuable than gold (hence the cap on the Washington Monument), and even today it's one of the most expensive common metals. Any improvement in smelting has great profit potential, so there's been a lot of advances aimed at improving the efficiency over the last century. The enormous energy inputs are getting pretty close to the minimums required to de-oxidize the aluminum (melting is incidental, and the thermal energy can mostly be recycled). There's a reason aluminum is nicknamed "solid electricity".
So the real question is how efficient the battery is at extracting energy from the oxidizing the aluminum. I too would like to know the actual numbers, but if it's capable of supplying power to a car without needing a large dedicated cooling system then that's pretty promising. And of course this is intended as an *auxiliary* power system only intended for use when the range of the primary batteries has been exceeded, so a much lower efficiency is acceptable - it exists primarily so that you never have to worry about being not quite able to make it home / to a charging station, though I could see it being nice for long road trips as well.
Given the inability to recharge them though, I do think I'd want 2+ batteries in the car, to be drained (and replaced) sequentially. I don't want my "emergency tank" anywhere near empty, but it's wasteful to recycle it while it's still 20% charged. So let me drain one completely while the next is still fully charged. Assuming I'm mostly driving on the primaries that also gives me a nice big time buffer as to when I replace the drained battery.
Re:haha. they call if "charging the battery" (Score:5, Interesting)
That's why you buy an EV whose primary, high-efficiency range is >= your normal daily usage. You add one of these just so that that isn't a hard limit - no need to worry about running out of charge a few miles from home because you ran a lot more errands than usual. Even if it cost 10x as much per Watt-hour as a primary battery charge that only mean only that, in the rare case when you exceed the range of the primary battery, your mileage costs increase 10x. Something to keep in mind, but if you only use the backup for a few % of your total mileage it won't significantly alter your operating costs.
Re:haha. they call if "charging the battery" (Score:4, Interesting)
The average car in the US travels approximately 20,000 miles/year. It's generally what they base warranties on and other things like leases .Some drive more, some drive less, but 20,000 average has held up for a long time now. (When you see those "160,000 mile/8 year power train warranty" - guess what!)
A battery that gets you 1800 miles per change would therefore require 11 changes a year, or just over a month's average driving.
You better hope that they have a regular battery in there and use the primary cell (yes, it's not recharging) as a range extender for those few trips that exceed the secondary cell capacity.
In this case, it'll be slightly better than those cars like the BMW and Volt that are primarily electric but tow a gas generator with them to offer extended range operations. This one keeps the existing simple low-maintenance electric drivetrain without having to add all the gas engine support components to the car.