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CATL has announced a new “condensed” battery with 500 Wh/kg

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Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#531

Earlier quoted context omitted.

To paint a rough and ready picture, aviation emissions are very heavily weighted towards richer, less populous countries, whereas electricity generation (and particularly fossil fuel generation) is (to a lesser degree) tilted towards where the mass of population is: https://ourworldindata.org/carbon-footprint-flying#:~:text=W... vs https://ourworldindata.org/grapher/carbon-intensity-electric... . Note that the colour…

I found some reference to Gatwick using 2.6 billion litres of fuel a year. If I follow the logic above I get circa 8 billion litres. I think most of this is because a Boeing 737 has a 3000nm range fully fueled which they wouldn't be using normally. In fact I suspect it's impossible to take off fully fueled and with a full complement of passengers (it certainly is for lighter aircraft). Between that and the efficiency…

That weight constraint cuts both ways though, right? An electric plane charged for a 500 mile flight weighs the same as one charged for a 2000 mile flight, and the max landing weight of (e.g.) a 737 is substantially lower than the max takeoff weight. That means the maximum passenger load of the electric plane can never be as high as one fuelled by an energy source that leaves the plane over the course of the flight. So yes it's more efficient in terms of direct energy use, but it's less efficient in terms of the ratio of work done moving the passengers to work done moving the vehicle, first because you can't stuff as many on, and second because the mass of the vehicle itself doesn't drop over time.

EDIT: unless, of course, you have removable batteries that let you carry less weight for a shorter flight. That might be the only way to make this practical, and would have some other benefits: you could charge them off-site, for instance. It creates a hell of a logistics problem, but no bigger than liquid fuel.

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#532
post #133

I just realized how much energy efficiency is being squeezed out of a Tesla. It's incredible. A normal diesel fueled sedan such as the Chevy Cruze diesel runs at about 31mpg, which is 13.2 km/l or 15.3 km/kg. Diesel has a mind-boggling 12700 Wh/kg energy density[1], which translates to an efficiency of ~827 Wh/km for the Chevy. By contrast, the Tesla Model S, has a ~540 kg battery[2]. At 272 Wh/kg (from the posted ar…

The big reason for this is thermodynamics. A conventional internal combustion engine car has to convert chemical energy to kinetic energy - the absolute best theoretical efficiency of this might be 70%, but in practice it's more like 30%. Electric cars have to pay the same thermodynamic penalty, but they pay it at the power station (In practice, thanks to renewables, not all the electricity used to charge a car will…

> Renewables change the picture though - once you have significant renewable generation the carbon intensity of electricity starts dropping, which means that remote powerplant vs local powerplant argument falls apart. That is when the real power of electric vehicles kicks in - they can take their energy from anywhere.

How close/far would you say we are as a society on "having significant renewable generation"?

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#533
post #276

Earlier quoted context omitted.

Well, they were already possible and being sold. But with relatively short but usable ranges. Those now more than double with this battery. Which makes those planes usable in a lot more scenarios. Consider the Eviation Alice, one of the 9 passenger prototype electrical planes that is currently undergoing test flights (i.e. it definitely works). The advertised range is 250nm. Not amazing. But far enough for a lot of r…

Just a naive question, would having 10 planes not also make personnel way more expensive - you’d need 20 pilots instead of 2? OTOH, security costs and airport fees could be cut I guess?

Also wondering this. A pilot’s salary divided 10 or 20 ways sounds like a lot to me.

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#534
post #110

Earlier quoted context omitted.

I’m afraid these bans get systematically sabotaged by well funded ice lobby groups. Just look at what happened to the EU’s ice ban for personal vehicles. Spoiler: while new gasoline burning cars are technically banned after 2035 it will be completely legal to sell new gasoline burning cars by labelling them e-fuel only…

Why would anyone want to use e-fuel in 2035 instead of electricity? (Except for "luxury" brands that just want to be special to distinguish themselves from the rabble.)

Well the FDP party which is in the coalition govt of Germany and torpedoed the EU ICE ban in the last minute and forced the inclusion of this e-fuel nonsense for the whole EU is run by a dude who likes to drive a Porsche and who is friends with the Porsche company. Porsche is the only major car producer in Germany that favors efuels. So uh, I think the FDP doesn’t like the ICE ban, because as a Laisser-faire party, they favor “open technology solutions” and want the “market” to decide on the best technological solutions for the climate problem.

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#535

Earlier quoted context omitted.

The Cruze is way better than that anyway, you'd need to be in an excruciating traffic jam to get that low mileage. Well, my 12 years old (gas) Honda Fit does +40MPG being very "pedal happy" and near 50 driving normally, and my dad's 20 years old (diesel) Citroen Xsara Picasso does around 60MPG

20 years ago was kind of a sweet spot for diesel automobile fuel efficiency. Emissions were terrible though. Then they tried to clean up the tail pipe emissions and lost most of the efficiency gains.

Yep, although they're becoming better again. Not that I'm a diesel apologist, I hate it, but I guess we're used to smaller and more efficient cars in Europe (even with the SUV craze)

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#537

500 Wh/kg means Sulphur cathode, which also explains the solid electrolyte. Roughly speaking, it'll be 3x as energy dense but only a 1/2 as volumetrically efficient (so, a given capacity battery will weigh 1/3 less but take up twice as much space). There are other approaches to Li-S (and Al-S and Mn-S) which will be less expensive. Grats to CATL for bringing this to market, but the race for sure isn't over yet.

Maybe volumetric inefficiency is where "condensed" part of the announcement comes in? Just spitballing here, would love to know more details.

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#538
post #133

I just realized how much energy efficiency is being squeezed out of a Tesla. It's incredible. A normal diesel fueled sedan such as the Chevy Cruze diesel runs at about 31mpg, which is 13.2 km/l or 15.3 km/kg. Diesel has a mind-boggling 12700 Wh/kg energy density[1], which translates to an efficiency of ~827 Wh/km for the Chevy. By contrast, the Tesla Model S, has a ~540 kg battery[2]. At 272 Wh/kg (from the posted ar…

The big reason for this is thermodynamics. A conventional internal combustion engine car has to convert chemical energy to kinetic energy - the absolute best theoretical efficiency of this might be 70%, but in practice it's more like 30%. Electric cars have to pay the same thermodynamic penalty, but they pay it at the power station (In practice, thanks to renewables, not all the electricity used to charge a car will…

>It's much easier to build highly efficient hydrocarbon power stations - typical efficiencies range from 40-60%.

Just to expound on this. Power stations turn fuel to heat, and heat to electricity via steam turbines.

In ICE cars, that heat is the main loss of power. Whole systems in cars are built to get rid of that excess heat in the engine.

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#539

Earlier quoted context omitted.

ICE cars also have to often go out of their way to the fuel pump, while most EVs are charged at home/office. There must be small impact of that as well to the CO2 calculations.

I mean, it's like, 50 yards out of the way? You stop at whatever gas station you're driving past. I don't know anybody who makes a specific trip to go fuel their car.

The existence and popularity of sites like gasbuddy.com suggests that some number of people are willing to go out of their way to find the lowest price. I personally know people who will make a run to Costco for gas, even if they're not going to go in for groceries, because the price is good. There are at least a half dozen gas stations on the way to Costco.

Re: CATL has announced a new “condensed” battery with 500 Wh/kg

#540

Earlier quoted context omitted.

I found some reference to Gatwick using 2.6 billion litres of fuel a year. If I follow the logic above I get circa 8 billion litres. I think most of this is because a Boeing 737 has a 3000nm range fully fueled which they wouldn't be using normally. In fact I suspect it's impossible to take off fully fueled and with a full complement of passengers (it certainly is for lighter aircraft). Between that and the efficiency…

That weight constraint cuts both ways though, right? An electric plane charged for a 500 mile flight weighs the same as one charged for a 2000 mile flight, and the max landing weight of (e.g.) a 737 is substantially lower than the max takeoff weight. That means the maximum passenger load of the electric plane can never be as high as one fuelled by an energy source that leaves the plane over the course of the flight.…

Also, one factor to take into consideration is that the 9GW figure assumes that the refuelling is uniformly distributed throughout the 24 hours. That won't be true, I could believe peak usage being double the average. If that's true, the worst-case 9GW isn't what you need to work to, it's 18GW peak. If we go with the 2.6 billion vs 8 billion L ratio as telling us the true power requirement, that gets us back up to 2.925GW average, 5.85GW peak.
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