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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

#331

Post by svnt »

leoedin wrote: post #189
msravi wrote: 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 is a sign of the success of the oil industry that this analysis always takes the cost of electricity generation back to the source, but assumes that fuel stations pump from a perfect source of naturally refined/distilled hydrocarbons.

It is surprisingly difficult to get numbers on how much oil is used to extract, refine and transport oil.

The best I found was this:

https://www.speakev.com/threads/energy-required-to-refine-oi...

Does anyone have better numbers?

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

#332

Post by lil_cain »

xnorswap wrote: post #285
spacebanana7 wrote: post #229

Earlier quoted context omitted.

I suspect the British fuel system is designed to hide the cost per mile of driving, at least tacitly. At present it's difficult to work out without some external tool.

We only switched to selling by the litre in the early 90s (presumably for the sake of EU alignment), it was sold in Gallons until then. Expressing efficiency in MPG is just something that had "stuck" by then.

UK was legally obliged to by the EU. See the "metric martyrs" for how weirdly controversial this all was.

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

#333

Post by pawelk »

AdrianB1 wrote: post #325
pawelk wrote: post #127

Earlier quoted context omitted.

Isn't it break even point, considering >60% of the gasoline energy is dissipated as heat, and <40% to make the wheels spin?

No, the number for gasoline is missing one zero; with the correct number, gasoline is still 6-8 times more energy dense per kg.

Thanks. I should have fact-checked the number before doing the math :)

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

#334

Post by crote »

theK wrote: post #283
geysersam wrote: post #202

Earlier quoted context omitted.

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.)

The core of the matter is this: They are only LABELED as e-fuel cars. You can run them just fine with classical fuels. EDIT: emphasis

A lot of gas stations have differently-sized nozzles for regular gasoline and diesel, and the fueling opening in the car is sized so that a diesel nozzle does not fit in a gasoline car. They should do something similar for e-fuel so people don't "accidentally" fuel them with classical fuel.

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

#335

Post by xxs »

msravi wrote: 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…

>runs at about 31mpg, which is 13.2 km/l or 15.3 km/kg

The measurements outside North America are reciprocal, e.g. 7.7L/100km (which is awfully inefficient for a diesel, normally it should be around 5L)

So converting gallon to liter, and mile to kilometer is the wrong way to present it.

As for the efficiency in general - of course electric engines have a very high efficiency (in the 90s), unlikely diesel which can barely hit 35%.

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

#336

Post by elihu »

idontwantthis wrote: post #4

Why does 500wh/kg make electric aircraft possible? 6x less than kerosene. Is that the break even on cost if you can source very cheap electricity? Seems like it would still annihilate the payload/range.

The point isn't necessarily to equal or beat kerosene in terms of weight and range, but rather to be good enough that electric aircraft are usable for many or most use cases.

Planes tend to be very expensive to operate, due to maintenance and fuel costs. Some people would be happy to trade range for dramatically lower operating costs.

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

#337

Post by jaystraw »

tpmx wrote: post #281
iSnow wrote: post #261

Earlier quoted context omitted.

I haven't heard of any country that wants to ban existing ICE cars.

The urban greens in the previous Swedish government coalition wants to ban fossil-based petrol from being sold starting 2030 - which economically speaking is kind of the same thing.

not if existing ICE vehicles can be sold -- unless they can't, that'd be an incredible waste

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

#338

Post by xxs »

mnw21cam wrote: post #218
msravi wrote: 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…

Maths check - 31mpg is 11km/l. (31mi/gal * 1.60934mi/km / 4.54609l/gal) Having said that, my 13-year-old normal sized diesel car does 60mpg in normal use.

Yeah but nobody actually uses kilometers per liter.

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

#339

Post by audunw »

krasin wrote: post #19
idontwantthis wrote: post #4

Why does 500wh/kg make electric aircraft possible? 6x less than kerosene. Is that the break even on cost if you can source very cheap electricity? Seems like it would still annihilate the payload/range.

Let's consider Cessna-172S ([4]). Its characteristics: - 130 kW engine, Lycoming_O-360 that weighs 117 kg. For comparison, an electric motor of this range would weigh 11-13 kg (at 10-12 kW/kg, [2]). That saves 100+ kg weight immediately and we can put 50+ kWh batteries instead. - It carries up to 200 liters of kerosene ([3]), which weighs 164 kg. We can place 82 kWh of batteries instead. - The engine consumes around…

For a direct conversion you could just look at the Alpha Electro

https://en.wikipedia.org/wiki/Pipistrel_Alpha_Trainer#Alpha_...

324 nmi range for the regular variant. Around 65 nmi for the electric version.

This is with older batteries, probably with very bad pack-level energy density. The battery pack can even be swapped. Great to avoid having to wait for charging, but probably terrible for weight.

If you design the aircraft for electric flight from the ground up (see Maxwell X-57 for how you could do that), with a structural battery pack, and with 300-500wh/kg batteries, I'm willing to bet a 2-5 times increase in range is viable.

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

#340

Post by frankfrankfrank »

VulgarExigency wrote: post #203
maccard wrote: post #194

Earlier quoted context omitted.

Even more confusingly, what the US calls a gallon isn't the same as what other countries call the gallon. It's about a 20% difference.

Not that confusing, only the US measures fuel in gallons, isn't it? Everyone else just uses liters.

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