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I don't know anything like enough in this field of EVs, so wondering if those smarter than me can help me work this out.

Tesla seem to be backing lithium-ion tech for the foreseeable future with the massive gigiddy factory, and most mainstream manufacturers seem to be taking (generally) the same route.

However on my G+ and twitter feeds I'm constantly seeing "new battery tech will revolutionise the world" "cars powered by fungi are the future" or other such incredible claims... but nobody seems to be really backing any other tech "full in" in the way they are li-ion...

What do you think the future holds, is there any kind of breakthrough likely within, say, five years?
 

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It's impossible to know what's coming in future because manufacturer's aren't exactly going to be too forthright with information about any significant progress in battery technology but if you look at past history you can say that progress is slow moving.

Along with comments like "new battery tech will revolutionise the world" and the fungi 'experts' you also often see people advising to lease an EV rather than purchase outright due to the fast moving battery technology. I've never been convinced about this. For example, the LEAF was first produced in 2010 so those that bought the first cars will be coming up to four years of ownership. So how far do you think battery technology has progressed in those 4 years ? The answer is very little progress at all and that remains the same for all manufacturers.

It's disappointing because we all want battery packs that give 500 mile range that can be charged in 5 mins but if you're thinking of buying an EV today I wouldn't let the threat of buying something that is going to be quickly obsolete put you off. It's clear to see that things aren't moving that fast and I'm guessing the answer to the question is YES :)
 

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No I don't think there's a wholesale change coming in five years. The theoretical energy density of lithium ion is some way off, so that's where the real research is focussed. There will be a slow transition to lithium air after that research starts drying up. Lithium air gets us to beating the (usable) energy density of liquid fuels quite quickly, and can then surpass that too, so the 300kg battery you find in a Leaf would be able to offer well in excess of 1,000 miles. I think that's 20 odd years away though.
 

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the LEAF was first produced in 2010 so those that bought the first cars will be coming up to four years of ownership. So how far do you think battery technology has progressed in those 4 years ? The answer is very little progress at all and that remains the same for all manufacturers.
If we use the often quoted 8% per year metric, and start with a 24kwh battery with 73 mile EPA range, then 4 years improvements give us 32kwh and 99 miles range, in a battery the same size and weight. That sounds like a realistic target for the majorly refreshed Leaf that goes on sale in 2016.

That same maths puts us on track for a 60kwh 185 mile Leaf in 2022. Still not exactly paradigm shifting, but getting there....!
 

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....you can bet Elon has thought a bit about this before signing off on the mega factory :)
 

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If we use the often quoted 8% per year metric, and start with a 24kwh battery with 73 mile EPA range, then 4 years improvements give us 32kwh and 99 miles range, in a battery the same size and weight. That sounds like a realistic target for the majorly refreshed Leaf that goes on sale in 2016.

That same maths puts us on track for a 60kwh 185 mile Leaf in 2022. Still not exactly paradigm shifting, but getting there....!
Wasn't it Renault who, late last year I think, said they were targetting 2020 for a 200-mile range car?
 

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I suspect that any new battery tech in the next five years or so will be Li-ion with different electrode or electrolyte material, rather than a completely different design. This means that a battery factory built today should still be doing well in eight or ten years. Further down the line there could be all sorts of interesting changes - but anyone who thinks they know what this will be is either a fool or a certified genius (I know which I would bet on ;))
 

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I don't know anything like enough in this field of EVs, so wondering if those smarter than me can help me work this out.

Tesla seem to be backing lithium-ion tech for the foreseeable future with the massive gigiddy factory, and most mainstream manufacturers seem to be taking (generally) the same route.

However on my G+ and twitter feeds I'm constantly seeing "new battery tech will revolutionise the world" "cars powered by fungi are the future" or other such incredible claims... but nobody seems to be really backing any other tech "full in" in the way they are li-ion...

What do you think the future holds, is there any kind of breakthrough likely within, say, five years?

You've touched on a huge subject area !!

Battery technologies like the aforementioned Lithium Air and similar have theoretical energy densities per unit mass of around 10 times that of existing standards. Their trick is that the bulk of the heavy internal chemical mix is replace by air flowing in/out which is much lighter, but there's huge problems with reactions between the battery internals and any incoming liquid like water !

There's also significant energy density gains to be had in the future by the development of Nanotechnology and Graphene based solutions, leading to tenfold increases in energy density or more, often cited as being on a par with energy density of petrol - that would be amazing, and I believe it will happen in the next decade or so. I also believe it will be throttled back by big oil and indirect government taxation methods ...

But commercial application of any of this is years / decades away because no matter what gets developed it will need a significant amount of validating / testing / refinement before its safe and cost effective for wide consumer use.

Besides advances in energy storage within EV's a lot can be done to lighten car structures whilst retaining strength, and other developments like load-levelling power demands with ultra capacitors or similar that extends the life of the main energy store.

Combine the proverbial battery advances of 8% per year (and the odd step change) with vehicle design and the rate of progress is probably more like 15-20%.

It also begs the question of what is the ideal range of an EV. We could theoretically have an EV with 1,000 mile range that sits outdoors harvesting all available solar energy, has regenerative shocks, and more efficient motor regen etc etc. But who actually needs to lug that much capacity about ? There's a balance point somewhere between 250 and 500 mile range where you just don't need much more for just use by the EV.

However, I quite like the idea of distributed energy storage where an EV is capable of storing energy for general use and that the EV can then be plugged back into the house when you're at home. An existing Tesla Model S can hold enough energy to power a conventional house for 3 to 4 days. If 10 million such 'mobile energy stores' were in use within the UK we could significantly reduce the need for national grids, building giant hydro storage schemes, and storing intermittent renewable energy that's often available when its not in demand and simultaneously build out masses of renewable energy harvesting systems because of the availability of a storage solution.

One downside at present is that most Lithium packs suitable for use in EV's have a low'ish number of charge cycles before capacity degradation, which is one reason why Tesla wont (yet) allow existing cars to have bi-directional power. But with 1,500-2000 cycles on the Model S before a mere 20% loss in capacity, the Model S is good for 300-400,000 miles. Blimey. Not many car reviewers have understood that.

I also believe that Tesla is pre-empting the forthcoming boom in distributed energy storage systems when planning the Gigafactory(s). This will be a huge growth area over the next 10 years...


Check out V2G links and ideas (Vehicle To Grid) :-

http://en.wikipedia.org/wiki/V2g

http://www.magicconsortium.org/research_partners.html
 

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An existing Tesla Model S can hold enough energy to power a conventional house for 3 to 4 days. If 10 million such 'mobile energy stores' were in use within the UK we could significantly reduce the need for national grids, building giant hydro storage schemes, and storing intermittent renewable energy that's often available when its not in demand and simultaneously build out masses of renewable energy harvesting systems because of the availability of a storage solution.
Yeah this aspect excites me too. If you have a car that has say 150kwh on board you'd barely notice 10kwh coming and going to feed the grid. Once all cars (30 millionish in the UK!) are EV's and a high proportion are plugged in during the day not moving we can absorb a truly massive amount of solar power. Let's be conservative and say only 10% are plugged in and free to charge/discharge to the grid, and only have 6kw charging systems. That's 18 gigawatts and we can store 30gwh. There's enough there to bang in 18gw of solar panels and turn off every coal plant in the country. If you legislate this, make it mandatory, and you get 75% of our 30 million cars plugged in and power buffering with 10kwh (not normally seen by the user, but does still act as an emergency "reserve tank" if needed) you have 225gwh and 135 gigawatts, triple (!) the entire grid demand. You could run the whole country off our cars for 5 days. In the scenario of all renewables, that means no sunshine and no wind (don't want to be in that world!) for 5 days and nothing changes. Realistically these would end up as almost seasonal buffers, getting up to the full 10kwh by the end of summer and running down to empty by the end of winter.
 

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Something that is reaching trial stages is Phinergy/Alcoa aluminium Air battery. That would not replace the li-ion battery but supplement it, providing long range when required. Since they have to be changed when depleted, the car would still need a conventional rechargeable battery for shorter trips. For my driving pattern, that would probably mean 1 or 2 changes a year as I rarely drive long distance.

That's a few years away but if that proves cost effective, that would completely rewrite the rulebook of the EV and make the weekly ICE refuel look as archaic as taking a delivery of charcoal to heat the house.

http://www.green-energy-news.com/arch/nrgs2014/20140016.html
 
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