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> But Goodenough is equally dismissive of such tinkering and its measly 7% or 8% a year in added efficiency.

7% extra efficiency per year means electric cars will have twice the capacity in 10 years...and then double up again in 10 more years...and so on. That's a far greater rate of improvement than for gasoline-powered cars, even if we're impatient and we want our $10,000 500 mile on a charge EVs now.

> But the path he has chosen involves one of the toughest problems in battery science, which is how to make an anode out of pure lithium or sodium metal. If it can be done, the resulting battery would have 60% more energy than current lithium-ion cells.

I don't know how "real" its technology is, but SolidEnergy promises a 50 percent increase in energy density using an "ultra-thin metal anode". The company promises commercialization for phones in 2016 and for EVs in 2017.

http://www.solidenergysystems.com/technology.html

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> I don't know how "real" its technology is

He's got an amazing track record.

> but SolidEnergy promises a 50 percent increase in energy density using an "ultra-thin metal anode". The company promises commercialization for phones in 2016 and for EVs in 2017.

The problem with battery tech is that it is a bit like solar: every year there are 10's of announcements like that, usually not from parties that have had such breakthroughs in the past. As is noted in the article since better battery tech is such an absolutely incredible breakthrough there is no shortage of those that would use this to their benefit absent any actual science.

So for battery and solar breakthroughs my personal hurdle is 'show me', until then I will happily wait by the sidelines (not as if it would matter in anyway if I didn't). But I'll give this particular scientist a break and I'll say that I will be much less surprised if he's going to the the one to nail the next substantial increase in battery efficiency. I hope the result will be as safe to use as Li-Ion or LiPo. We're getting to the point where chemistry of explosives and chemistry of batteries is quite comparable and that's one reason why this is such a hard problem. Making a better stable battery is the hard challenge. And LiPo is pushing it there, those are not batteries I'd want on my person or in a spot where they can cause a lot of damage when they go.

> 7% extra efficiency per year means electric cars will have twice the capacity in 10 years...and then double up again in 10 more years...and so on.

An example of the dangers of extrapolating.

CPU speeds kept going up - until they didn't.

Battery tech is not going to keep going up 7% each year. Although perhaps his 60% improvement will show exactly at the right time to effectively be 7% better than the previous year.

CPU speeds stopped increasing because the market stopped focusing on CPU speed (coincidentally to this discussion, the change was largely to reduce power demands). Transistor count has kept plugging right along;

http://i.imgur.com/FvVrnn4.png

I think it is misleading to say it was due to reduce power demands. Rather it was due to needing to cool the damned things. If you were to have a 500W TDP chip, you would either need a crazy huge cooling system or a much bigger surface area. Consumers want light and thin, so Bob's your uncle.

Even if consumers were fine with big heavy things (and except for maybe phones, I don't think the CPU weight/size are an issue for consumers), light travels roughly 1ft/ns. You want fast, you have to be small.

I think it's the other way? That is, market stopped focusing on CPU speed because they hit the wall and clock speed could no longer be used as a differentiating factor.

Yes, market would be more than happy to have 100GHz CPUs by now, it would make scaling everything much easier.

Surprised by the negative reaction.. More technically, processor speeds required far more electricity to increase clockspeed which required much more energy to disappate in the form of fans and heatsinks.

We are actually not so far away from hitting the ceiling with batteries. There are fundamental physical reasons for why you can't put much more than 1eV per atom in a battery. That equates roughly to 850 Wh/kg, if memory serves, and we are currently pushing Li-ion towards 300 Wh/kg. So we can only keep growing at 5% for another couple of decades or so. Regardless of battery chemistry.

What people often do to hide this fact is talk about energy density, Wh/L, where growth can continue for longer, at the expense of making batteries heavier.

Gasoline manages 12kWh/kg, and I'm sure I've heard people talking about batteries at least approaching that density before, even if only on a theoretical basis.

Leaving aside how safe I'd feel with a supercap of that density under the hood, are you sure about the 800Wh/kg limit? I'd be very interested in seeing a reference.

Found this article discussing some limits http://chargedevs.com/features/three-of-a-kind-polyplus-reac...

The 1eV per atom is really a rule of thumb, but easy to understand: At that value you are getting dangerously close to the ionization energy 13.6 eV for hydrogen, 5.4 eV for lithium), so you can no longer have a chemical battery. Note also that this is average eV for all atoms in the battery, so those actually providing electricity will be carrying atound 1.5 - 2 eV.

See e.g. here: http://www.ohio.edu/people/piccard/radnotes/radioactive.html

SolidEnergy also looks like it has a solid team behind it as well.

http://www.solidenergysystems.com/people.html

Having done a little science myself, usually there both are small incremental improvements with small but predictable gains and large leaps with big potential gains but very unpredictable outcomes. The former are optimizations around a current local optimum, and the latter try to escape it towards a better local optimum. For that reason the incremental gains tend to saturate over time, and I suspect that is what Goodenough is dismissing.

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