CATL has announced a new “condensed” battery with 500 Wh/kg • Hacker News Board

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

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Post by dclowd9901 » Fri, Apr 21, 2023, 2:13 PM UTC

cfiggers wrote: post #403

svnt wrote: post #331

Earlier quoted context omitted.

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-t…

> It is surprisingly difficult to get numbers on how much oil is used to extract, refine and transport oil. Damn, I've never thought about that before. In hindsight that feels like an obvious thing to consider but this is the first time I'm aware of that thought entering my brain. Thank you for provoking the thought. What would be the equivalent consideration on the other side? Would it be something like inquiring in…

It’s not something we often consider because, again, the energy density of carbon fuels _is a couple of order of magnitudes higher_ then batteries. It seems trivial because a fuel hauling truck is an _absolutely immense_ source of energy compared to the energy it consumes to move.

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

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Post by marcosdumay » Fri, Apr 21, 2023, 2:14 PM UTC

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…

> A conventional internal combustion engine car has to convert chemical energy to kinetic energy - the absolute best theoretical efficiency of this might be 70%

You mean thermal energy?

Both cars are converting chemical energy to kinetic. The theoretical maximum for this is 100%. But one uses a thermal intermediate step, that reduces that maximum.

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

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Post by nayuki » Fri, Apr 21, 2023, 2:14 PM UTC

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?

Note how almost every diesel locomotive has electrical generators and motors as an intermediate step because they decided that it's cheaper, more efficient, and/or lighter than having a huge gearbox. Electrification has some real advantages. https://en.wikipedia.org/wiki/Diesel_locomotive , https://en.wikipedia.org/wiki/Diesel%E2%80%93electric_powert...

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

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Post by Consultant32452 » Fri, Apr 21, 2023, 2:15 PM UTC

zamnos wrote: post #399

osigurdson wrote: post #345

Earlier quoted context omitted.

Most power generation facilities are natural gas fired, using large aero derivitive gas turbine engines (essentially the same engine that is in the 747 - LM6000 vs CF6 for example) with a combined cycle steam turbine to capture the energy from excess heat. This arrangement has a thermodynamic efficiency of 60%. Even with electrical transmission losses, the efficiency is still far better (1.7X) than having the power p…

Not to mention, policing one large facility for compliance with emissions is much easier than trying to monitor every single one of millions of cars on the road.

It's much easier to regulate millions of nobodies with no power than it is to regulate a single wealthy donor.

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

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Post by osigurdson » Fri, Apr 21, 2023, 2:15 PM UTC

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…

This is definitely not an apples-to-apples comparison. With an EV the ball is already at the top of the hill and merely needs to be rolled down, with an ICE car, the ball has to be pushed up the hill first. The power plant does all of the heavy lifting for the EV.

Not a mark against EVs of course - it kind of just makes sense. I'm sure future generations will laugh that every vehicle used to have its own on-board power generation facility. It's too bad the dumb power-plant-under-hood way is still so much cheaper than the EV approach of course.

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

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Post by oblio » Fri, Apr 21, 2023, 2:16 PM UTC

imiric wrote: post #244

oblio wrote: post #162

Earlier quoted context omitted.

> Electric planes could recharge using solar or wind. As efficiency increases with these technologies, it would mean planes wouldn't require carrying the same watt-for-watt energy as fuel. Those are pipe dreams :-))) Solar recharging for electric cars is not realistic, let alone for electric planes. Wind charger... maybe there's something there, but the fact that nobody has tried it probably means it's not good enoug…

Planes have a much larger surface area to carry solar panels, and they fly above clouds, so have clearer access to sunlight than cars do. Wind charging is more of a pipe dream, but there's no reason a plane couldn't glide for a period of time to get some energy back, similar to regenerative breaking. There have been experiments in both areas, and while it's certainly unfeasible today for any large aircraft, the techn…

> Planes have a much larger surface area to carry solar panels, and they fly above clouds, so have clearer access to sunlight than cars do.

And the energy they require for flying is an order of magnitude than that required to drive stuff on the ground.

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

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Post by oblio » Fri, Apr 21, 2023, 2:17 PM UTC

bb123 wrote: post #264

oblio wrote: post #142

Earlier quoted context omitted.

That's about the same efficiency as every modern EV. This is not Tesla specific. Electric motors are very efficient, regenerative braking helps, EVs are designed to be super aerodynamic, etc.

That is not quite true - you’re right that it is not Tesla specific but many current EVs are far less efficient: https://insideevs.com/news/567087/bev-epa-efficiency-compari... Particularly German made ones, for some reason.

For US models :-)

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

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Post by the_third_wave » Fri, Apr 21, 2023, 2:18 PM UTC

XorNot wrote: post #422

the_third_wave wrote: post #400

Earlier quoted context omitted.

You are pointing at a single year, I am pointing at a trend [1,2]. The trend had been for the average global temperature to rise up to 2012 to 2016 - depending on which measurements you look at. After that period the average global temperature has declined by 0.06°C per year up to 2022. This change in the trend made the "global warming" moniker easily attacked "because the temperature are clearly going down". This is…

Wow didn't even wait before busting out "what if CO2 doesn't cause global warming" and very obviously didn't read your own links. Running the denialist playbook as usual: slip in a insinuation that the issue has stopped without evidence, then drop a bunch of articles which don't support it while continuing to say "what if all the data supported me?" And then started alluding to a conspiracy with language choices like…

Climate cycles are natural [1].

Please refrain from using terms like denialist, it does nothing to help the discourse. Also, that 'bunch of articles' I sent does support what I said, this being a break in the rising temperature trend. You seem to want to hear much more in what was said, why is that?

As to the 'conspiracy with language choices' I think you realise that this is no conspiracy but a simple fact - what used to be called 'global warming' is now called 'climate change'.

As to 'tone policing' I'd suggest reading your posts I replied to.

[1] https://en.wikipedia.org/wiki/Holocene#/media/File:Holocene_...

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

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Post by steveBK123 » Fri, Apr 21, 2023, 2:18 PM UTC

dahfizz wrote: post #460

steveBK123 wrote: post #444

Earlier quoted context omitted.

Relative efficiencies also explain why city/highway efficiency is inverted between EV & ICE. Gasoline is rather energy dense, but the ICE is rather wasteful. There is a certain base load of energy being generated by an ICE engine, regardless of if you are moving or how slow you go. This is why carmakers experimented with things like rapid stop/start engines, regen batteries&motors, etc. ICE becomes more efficient as…

Meh, the only reason EVs are more efficient in the city is because of regen braking. An ICE car traveling at a constant 30mph is going to get much better fuel economy than an ICE car traveling at a constant 75mph. The difference is that <=30mph roads usually have a lot of stop-and-go.

ICE efficiency also more driven by RPM & therefore where you are in the gears. So ICE designers have decisions to make about which speeds to optimize for.

ICE peak efficiency tends to be more around 45mph than 30mph.

But yes, the less you brake in an ICE, the more efficient. Hybrids give you a bit of the ICE range/highway efficiency with the EV city driving efficiency, with the added complexity of having ICE & EV under one hood.

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

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Post by acidburnNSA » Fri, Apr 21, 2023, 2:19 PM UTC

jjtheblunt wrote: post #385

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…

Does regenerative braking count as renewable energy? It's clearly absent from internal combustion (diesel or not)

Lord I hope not. It helps with efficiency, but is no more renewable than carrying a rock upstairs and throwing it out a window onto some kind of generator.