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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

#281

Post by tpmx »

iSnow wrote: post #261
cultureswitch wrote: post #204

Earlier quoted context omitted.

The timelines for ICE bans within a decade are ridiculous from a technology and market standpoint and terrible for the environment. The best car technology is the one you don't use much. And we already have decades of cars in good enough condition to be driven weekly rather than daily. EVs will barely scratch the surface of environmental issues with transportation. And they will create a new range of supply problems…

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.

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

#283

Post by theK »

geysersam wrote: post #202
theK wrote: 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.)

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

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

#284

Post by rcxdude »

2OEH8eoCRo0 wrote: post #258
leoedin wrote: post #189

Earlier quoted context omitted.

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…

ICE converts chemical energy to mechanical energy but an electric vehicle still has to convert electrical energy to mechanical energy.

This is a much more efficient process: somewhere between 75 and 95% efficiency, depending on the motor and the exact speed and torque (and of course they try to optimise for the best efficiency around the common operating points)

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

#285

Post by xnorswap »

spacebanana7 wrote: post #229
grosun wrote: post #212

Earlier quoted context omitted.

The UK may be the most confusing; fuel is sold in litres, but fuel efficiency is expressed in MPG, and furthermore the gallons aren't the same as US gallons. I guess at least the miles are the same!

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.

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

#286

Post by numpad0 »

walrus01 wrote: post #250
leoedin wrote: post #189

Earlier quoted context omitted.

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…

> A modern series hybrid like a Toyota Prius is effectively an electric vehicle and a gas generator (which means it has the same efficiency gains due to regenerative braking). That gets 52 mpg, which is about 493 Wh/km. Wait, does a new prius or something like a hyundai ioniq (also 52-53 mpg) not have the internal combustion engine mechanically coupled to the transmission and drive wheels anymore?

No, it’s just reframing. Prius is still that transverse mounted engine going into the torque splitter gear with two motors sandwiching it.

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

#287

Post by littlestymaar »

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…

> which is ~27% of the energy required to run a normal car!

This is because you're not comparing the same things: going from thermal energy to mechanical energy has a much lower efficiency than going from electricity to mechanical energy. But that electricity has to come from somewhere, and most of the losses happen at the electricity generation place instead of in the car.

> It just wouldn't have been possible to run cars on batteries without this efficiency bump.

Electric motor have always been far more efficient than ICE ones, even in the 19th. In fact, the difference was even bigger, because combustion engine sucked hard back then, whereas electric engine didn't make as much progress as combustion engine ones (that doesn't mean that they didn't make progress, they did, but there's far less of a difference between an electric engine of 1920 and the one in a Tesla, than between an ICE engine then and now).

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

#288

Post by sidewndr46 »

2OEH8eoCRo0 wrote: post #279
robnado wrote: post #271

Earlier quoted context omitted.

The battery converts from chemical energy to electrical energy and the motor of the vehicle converts from electrical to mechanical energy.

Ah. My point was more that there are losses assocated with these conversions and you can't move all of it to the upstream power plant. ICE vehicles burn fuel and create rotational mechanical energy which other than gear reductions doesn't require conversion. Electric does chemical -> electrical and then electrical -> mechanical with losses at each step here right?

Not entirely true, most transmissions have a system of torque converters and clutches. The torque converters convert rotational energy into fluid pressure to gain a kind of mechanical advantage. The clutches slip and make heat, usually to allow other parts of the transmission to interact without destroying gears.

Once you get to cruising speed the transmission usually engages something called a "lockup" that bypass all that to get as close to the 100% number for energy transfer as possible.

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

#289

Post by sidewndr46 »

rimliu wrote: post #267
walrus01 wrote: post #250

Earlier quoted context omitted.

> A modern series hybrid like a Toyota Prius is effectively an electric vehicle and a gas generator (which means it has the same efficiency gains due to regenerative braking). That gets 52 mpg, which is about 493 Wh/km. Wait, does a new prius or something like a hyundai ioniq (also 52-53 mpg) not have the internal combustion engine mechanically coupled to the transmission and drive wheels anymore?

I've got Civic e:hev, which has kind of similar setup. ICE does drive wheels in some situations (high speed, much power required), but mostly is just EV. It does not even have a gearbox, so there is only direct coupling from ICE to the wheels that can be engaged or disengaged (this is done automatically, you have no manual control over this). I really like this setup, because it gives economy, but also a range and I…

Isn't Honda the dark horse of hybrids? I remember riding in one and the owner explained that apparently Honda chose a hybrid architecture that was different that everyone else. The car's transition from electric to ICE was quite noticeable.

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

#290

Post by chemmail »

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.

My house alone makes 12-14kWh of electricity a day. Do that to some land near an airport and it will be almost free.
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