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The rise of batteries in six charts

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Re: The rise of batteries in six charts

#231

Post by doubleg72 »

stcredzero wrote: post #199
lancewiggs wrote: post #173

Earlier quoted context omitted.

And stop using streets for car storage, opening them up to people and plants.

Bandaid-ing plants and naively making public spaces often doesn't work in the US. It's a little more work to make spaces where people actually want to be. Look at the numerous existing city public spaces built into high profile architecture, where basically no one ever hangs out in. (There's a TED talk about this.)

Why would their worth be determined on how many people hang out there? I prefer to see green spaces and am okay appreciating them from a distance, such a in a nearby town with a tree lined main street through town. I don't think it would invoke the same aestetic pleasure with people and litter occupying these spaces.

Re: The rise of batteries in six charts

#232

Post by adgjlsfhk1 »

tonymet wrote: post #104
Tade0 wrote: post #67

Regarding price, leading manufacturers are already selling at a price below what was always understood as the point where EVs win in terms of economics: https://www.nextbigfuture.com/2024/01/ev-lfp-battery-price-w... The recent price war in China is a testament to that.

why aren't consumers seeing this price yet?

https://electrek.co/2023/10/05/tesla-prices-keep-dropping-mo... they are.

Re: The rise of batteries in six charts

#233

Post by aswanson »

xxs wrote: post #225
alted wrote: post #201

Earlier quoted context omitted.

Excellent question! A sufficiently advanced battery can theoretically beat gasoline. Any given energy storage technology can store a maximum amount of energy in a fixed volume or mass. Behold one of my favorite plots: [1] From lowest to highest energy density: - springs, which use mechanical elastic potential energy, are kinda horrible - capacitors, which use electric permittivity, aren't great - next are both batter…

Fuel(gasoline, carbohydrates, fats, etc. but not rocket one) does use oxygen from the atmosphere.Batteries are self contained (like rocket fuel). So the density of chemical reactions is by definition higher. Side note: energy density should apply to volume, not weight, but we'll - it is too common now.

What makes one chemical more able to store a greater energy per unit mass than another? Wouldn't the theoretical limit be a volume of pure electrons compressed in the densest unit volume possible? Say, stored in a magnetic field?

Re: The rise of batteries in six charts

#234

Post by radium3d »

XorNot wrote: post #206
Gibbon1 wrote: post #154

Earlier quoted context omitted.

The amazing thing is there basically were no batteries three four years ago. And they can supply about 10% of the max power demand already. So it feels like the technologies we need are now good to go on an engineering an accounting basis. And adoption can be quite rapid. We're not saying in 50 years, 25 years, 10 years. We're looking at 5 years.

"power". This doesn't mean anything. LiFePO4 scales power to energy storage at a rate of about 1:3-1:4. 1GW of "power" they can supply for 4 hours if you completely discharge the battery. But that's it. Batteries could supply 100% of the grid briefly, and you still wouldn't be anywhere near having completed a switchover.

You can see by the graph that the batteries don't piddle out that quickly already.

Re: The rise of batteries in six charts

#235

Post by goodSteveramos »

_aavaa_ wrote: post #158
slingnow wrote: post #105

Earlier quoted context omitted.

"Doesn't matter as much as people think" Doesn't matter for WHAT? You start out talking about energy density, and then cite some numbers regarding efficiency. What does one have to do with the other? You've done nothing to support your opening claim here.

"Energy" value of gasoline and "energy" value of a battery pack are measuring two very different things even though they are both units of energy. When you burn gas in an engine, the engine has a theoretical upper limit on its efficiency which is FAR below 100%, and electric vehicle does not. So saying that gasoline has an energy content of 115,000 BTU/gal doesn't mean much since you'll be lucky to see 30% of that be…

Well, acording to wikipedia gasoline has an energy density of 46.4 MJ/Kg and LiPo batteries have an energy density of 0.36–0.875 MJ/Kg. So if your electric drivetrain has a 100% efficiency and your gas drivetrain has a 30% efficiency then the gasoline car would be able to do 16 times more work per unit of fuel.

Re: The rise of batteries in six charts

#236

Post by drtgh »

XorNot wrote: post #210
drtgh wrote: post #203

Earlier quoted context omitted.

>Petrol's higher energy density doesn't matter as much as people think. When vehicles uphill, ramp, and fight with the increasing wind resistance due speed, it is needed a high torque for to motion. The petrol's energy density is translated in high torque, that the gearbox latter transforms progressively. In electric vehicles, generating high torque and cooling the overheated coils for to obtain such high torque drai…

This is completely wrong: an ICE has 20-25% of the energy of petrol to use to do all those things. The rest is lost as heat.

Regardless of theorical efficiency or not of the energy, in practice the ICE gets the torque needed by the vehicle for driving on all types of slopes (and speed, by transforming part of that high torque with the gearbox).

This is why electric and combustion vehicles have such different ranges at even the same weight. Nowadays.

Such high torque is needed at the same moment the vehicle doesn't circulate on a flat terrain, or when have to reach highway speeds.

For to get at least the same ranges, the electric vehicle must reduce the energy consumption for the generation of the required torque (and speed), or needs to increase the energy density of the battery in companion of increasing the recharge cycles.

will be possible to achieve this? of course.

(The losses cooling or heating the battery and avoid the self-discharge should get the same advances, as it's counted as stored energy but it's not used for motion)

Re: The rise of batteries in six charts

#237

Post by goodSteveramos »

slingnow wrote: post #105
thelastgallon wrote: post #20

Earlier quoted context omitted.

> I'd like to see the the energy density of petrol for comparison. Petrol's higher energy density doesn't matter as much as people think. Electric vehicles are around four times as efficient as petrol. In a petrol car, only 20% of the energy is converted to motion. In electric cars, this is around 80% (with some variation dependent on regenerative braking). I wrote about this extensively in a previous article: https:…

"Doesn't matter as much as people think" Doesn't matter for WHAT? You start out talking about energy density, and then cite some numbers regarding efficiency. What does one have to do with the other? You've done nothing to support your opening claim here.

Yea it doesn't really follow. I think the idea is that the energy density being 50 times lower doesn't matter because the battery is efficient enough that you can make an EV with a 300 mile range which is good enough for most people. Of course if anyone wanted one, you could build a gas car with a 5,000 mile range if it had a gas tank as massive as an EV battery.

Re: The rise of batteries in six charts

#238

Post by dalyons »

zizee wrote: post #197
cbmuser wrote: post #191

Earlier quoted context omitted.

Fossil fuels are not going anywhere soon as a quick look at the world’s energy mix proves. > https://ourworldindata.org/grapher/global-primary-energy

Thanks, but that does not answer my question. I guess I want to hear predictions of when fossil fuel usage will peak, and over what time period will it be reduced by 20, 30, 50%.

The IEA says it will peak in 2025. And they have consistently underestimated predicted renewables growth VS actual every year for the last decade.

https://www.iea.org/news/the-energy-world-is-set-to-change-s...

Re: The rise of batteries in six charts

#239

Post by bmicraft »

adgjlsfhk1 wrote: post #232
tonymet wrote: post #104

Earlier quoted context omitted.

why aren't consumers seeing this price yet?

https://electrek.co/2023/10/05/tesla-prices-keep-dropping-mo... they are.

Tesla is both a luxury car brand and the single most unreliable brand. The masses need an actually cheap and reliable ev, not whatever this is.

Re: The rise of batteries in six charts

#240

Post by goodSteveramos »

adgjlsfhk1 wrote: post #232
tonymet wrote: post #104

Earlier quoted context omitted.

why aren't consumers seeing this price yet?

https://electrek.co/2023/10/05/tesla-prices-keep-dropping-mo... they are.

This is Tesla's margins collapsing because of less than forcasted demand for luxury vehicles. Battery prices have dropped much more slowly than the prices of EVs.
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