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The rise of batteries in six charts

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Re: The rise of batteries in six charts

#251

Post by tonymet »

Sohcahtoa82 wrote: post #242
tonymet wrote: post #166

Earlier quoted context omitted.

typical hackernews climate thread -- don't ask any important questions

They're bad faith, loaded questions. Be honest, you didn't ask them to learn something, you asked them because you think they're "Gotcha!" questions. Your responses to answers make this painfully obvious. If you want to make a point, then just make it. Don't hide behind a bullshit claim that you're just asking questions and then cry about downvotes.

Every solution has tradeoffs . What is so wrong about discussing them. We discuss the tradeoffs of everything else. Then electric comes up and that’s off limits

Re: The rise of batteries in six charts

#252

Post by dagss »

mauvehaus wrote: post #214
axiolite wrote: post #200

Earlier quoted context omitted.

> I cannot reasonably run lengths of 110v extension cords down the block to charge a car overnight, and acquiring my own house with a garage is dramatically more expensive You don't need a garage, just some sort of reserved parking space... There are plenty of weatherproof electrical boxes. It costs a bit of money to have a trench from your home to your car parking area, but far less than buying a house. And that "11…

A 6-30 NEMA connector still only supplies 30 amps. 30A x 240V = 7200W. Which is under 10hp. You're still looking at an awfully slow charge.

My bet is probably 90% (99%?) of home charging is done at 7.2kW or less. 7.2 kW is in the higher end, not "awfully slow". Myself I often charge at 3.6 kW.

Re: The rise of batteries in six charts

#253

Post by DrNosferatu »

erikpukinskis wrote: post #222
DrNosferatu wrote: post #219

Without log axis, this is all very opaque... Also, battery-powered >=737-size passenger airplanes (also not so sure about trains and cargo ships) will need at least a revolution in battery technology - batteries won't do, they're just too heavy for the little energy they output: https://en.wikipedia.org/wiki/Energy_density#In_energy_stora...

I doubt there’s any reason why trains couldn’t run on batteries. Anything that either stops and then starts again before refueling, or goes down and then up again before refueling, should be compatible with batteries due to regenerative braking. Trains have both of those properties. Planes have neither of those properties which is what makes them hard to run off batteries. Cargo ships also wouldn’t seem to have a pro…

Here’s why:

You would need a whole other ship full of lithium batteries in tow so a useful size cargo ship would have the enormous energy required for a regular cargo trip.

Trains work better, but charge time would impact operation feasibility, and just electrifying the railway with overhead cables is currently cheaper than lithium battery solutions.

Hence the case for hydrogen fuel cells for train applications.

Re: The rise of batteries in six charts

#254

Post by rstuart4133 »

LUmBULtERA wrote: post #51
aresant wrote: post #4

This is all very encouraging and in particular batteries role in solar Two interesting data points to that end 1) The "duck curve" for CA is almost neutral - eg the timing imbalance between peak demand and solar power generation - battery utilization is the most straightforward solution here - https://twitter.com/baker_edmund/status/1750644294673748366 2) There has been a massive decline in rooftop solar applications…

Given the dramatically lower costs of utility-scale solar vs. residential rooftop solar, is it not better at a society level for state policy to incentivize utility over residential solar? Utility-scale battery installations likewise should be much cheaper.

> Given the dramatically lower costs of utility-scale solar vs. residential rooftop solar

According to Wikipedia the LCOE on small roof top solar is about twice that of utility solar. [0] So yes, it's dramatically better. But typically the price difference between what the utility is paid and what the customer is charged is 3 times, so your average household is better off installing solar despite generating it at twice the cost of a utility.

The price difference isn't just transmission costs. It's also retail markup, regulatory charges and metering and billing.

[0] https://en.m.wikipedia.org/wiki/Cost_of_electricity_by_sourc... - there are a lot of tables in that page. Twice looks to be generous to the utilities.

Re: The rise of batteries in six charts

#255

Post by xxs »

aswanson wrote: post #233
xxs wrote: post #225

Earlier quoted context omitted.

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?

Compressing neon gas won't do much, aside storing energy as compressed fluid.

My point was the traditional fuels (incl. the edible ones) use more material/weight than their own. So it is very likely they'll be more efficient. The batteries require a reversible action by just applying current - this is quite the climb compared to most chemical reactions.

We have not done much since the li-ion inception, using FePO4 instead of cobalt is more sensible from an economic point of view but the energy density is even lower.

Re: The rise of batteries in six charts

#257

Post by londons_explore »

strangemonad wrote: post #82
zardo wrote: post #72

Earlier quoted context omitted.

> Tesla will be saving $800 in LFP battery costs within 6 months and another $800 within about 18 months. Do they have a model using LiFePOs now?

Many of the china model 3s and Ys use prismatic cells from CATL use lifepo chemistries

I think the reason for the wide variety of battery tech in Tesla's model range is partly to reduce/spread costs incase one battery is found to catch fire/fail when it hits 7 years old.

Re: The rise of batteries in six charts

#258

Post by _aavaa_ »

goodSteveramos wrote: post #235
_aavaa_ wrote: post #158

Earlier quoted context omitted.

"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.

And yet, electric cars you can by today don’t have 1/16th the range of a gasoline car. So energy density is not enough.

Re: The rise of batteries in six charts

#259

Post by ceejayoz »

bmicraft wrote: post #241
cogman10 wrote: post #134

Earlier quoted context omitted.

Demand far outstrips manufacturing capacity at the moment. For batteries not put in EVs a slightly lower price will get them installed in grid storage solutions. Consumers will be the last to see lower prices while demand outpaces supply.

I really don't get how battery manufacturers have have the better part of a decade of with batteries sold pretty much before they've been manufactured and still haven't scaled up to capture that demand

They have. The very first chart in the article clearly shows that.

Demand just keeps increasing, too.

Re: The rise of batteries in six charts

#260

Post by ceejayoz »

goodSteveramos wrote: post #235
_aavaa_ wrote: post #158

Earlier quoted context omitted.

"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.

> then the gasoline car would be able to do 16 times more work per unit of fuel

OK, so we've got ~300 mile range electric cars.

Where are the 5,000 mile range gasoline cars?

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