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The rise of batteries in six charts

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Re: The rise of batteries in six charts

#121

Post by robocat »

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.

From linked link[1]: CATL is marketing 173-Ah VDA spec (Rectangular cells: 148mm length, 26.5mm width, 91 mm height - German specification).

I presume manufacturers make packs using whatever cell sizes they can source?

I had thought the trend was away from cylindrical (eg 4680) and towards prismatic or pouch cells? Whatever happened to the 1 metre long BYD cell: https://pushevs.com/2020/05/26/byd-blade-prismatic-battery-c...

[1] https://cnevpost.com/2024/01/17/battery-price-war-catl-byd-c...

Re: The rise of batteries in six charts

#122

Post by jauntywundrkind »

cperciva wrote: post #89
letuv wrote: post #50

Are these 500 Wh/kg batteries somehow available in powerbank (sub-500g) size? So far the best I found are around 250 Wh/kg (for the whole powerbank).

You'll have trouble finding powerbanks over 100 Whr, due to FAA regulations.

I wonder when if ever we'll see this re-evaluated.

It's still a terrifying amount of energy, but I'd feel much much different about someone with a 300WH LFP pack sitting next to me than I would a lipo pack.

Re: The rise of batteries in six charts

#123

Post by sandworm101 »

Take 25% of the money spend on EV batteries and instead spend it on domestic solar panels. I cannot stand the smugness of people who will pay $$,$$$ for a car but won't spend $,$$$ on the thing to make power for that car. Even batteries. The net carbon saved by in-home battery+solar is far more than putting batteries in the family car. The car runs a few hours a day. A total off-grid solar+batteries domestic system saves carbon 27/7.

In other words, (Honda civic IC + home solar/batteries) saves more carbon than a Tesla with no actual power generation capacity. But that just isn't fashionable.

Re: The rise of batteries in six charts

#124

Post by Phenomenit »

NotSammyHagar wrote: post #47
Phenomenit wrote: post #39

Earlier quoted context omitted.

What is the use case of long term storage in batteries? As some kind of reserve?

Depends on what long term means. But batteries are used for power grid storage. Tesla is selling huge numbers of tesla megapacks ( https://en.wikipedia.org/wiki/Tesla_Megapack ) often used to replace peaker plants. Peaker plants are power plants sitting there ready to turn on during peak power usage. I think they used to be often coal, which took a while to start up and produced lots of pollution, but then more recen…

Yeah, I think my question was a bit fuzzy, what is the definition of long term? Batteries are excellent for short term storage, days or weeks but they don’t have the same storage performance as fossil fuels of where talking months and years.

Re: The rise of batteries in six charts

#125

Post by candiddevmike »

sandworm101 wrote: post #123

Take 25% of the money spend on EV batteries and instead spend it on domestic solar panels. I cannot stand the smugness of people who will pay $$,$$$ for a car but won't spend $,$$$ on the thing to make power for that car. Even batteries. The net carbon saved by in-home battery+solar is far more than putting batteries in the family car. The car runs a few hours a day. A total off-grid solar+batteries domestic system s…

From my interaction with local utilities/electrical companies, they _hate_ domestic solar. They'll do everything in their power to stonewall you getting them installed and make it seem like a useless/expensive option.

Re: The rise of batteries in six charts

#126

Post by ceejayoz »

dylan604 wrote: post #108
deadeye wrote: post #103

Chart #2: Top Tier Energy Battery Density vs. Battery Cost. That seems like an odd comparison to me. Is it normal to compare the Top Tier Anything to the Average of another thing? Top Tier Car 0-60 Times vs Average Car Costs? IDK, it doesn't seem to contain any REAL information. Shouldn't the comparison be the costs of the SAME cars and not include cars that aren't top tier? What am I not getting?

Chart 2 definitely seems strange as it appears that batteries are free in 2023

Only because it's a wide line.

Cost is $139/kWh, which on a scale of 0-9000, is pretty close to zero historically. https://about.bnef.com/blog/lithium-ion-battery-pack-prices-...

Re: The rise of batteries in six charts

#127

Post by Sohcahtoa82 »

donbatman wrote: post #62

Most of those batteries are being charged by natural gas. Batteries store electricity, they don't create it.

It frustrates me that you think this is a genuine talking point.

If we're talking about powering cars, then even if your power comes from 100% coal, it's still cleaner to drive the EV than gasoline, simply because the coal power plant benefits from the economy of scale. It merely takes longer for the trade-off of the higher carbon footprint of manufacturing an EV to happen. But it does eventually happen.

If we're talking about powering an energy grid, nobody expects them to be charged via consumables. That's just silly. But battery storage is how you make wind/solar energy work without requiring burning consumables as a backup.

Re: The rise of batteries in six charts

#128

Post by LUmBULtERA »

epistasis wrote: post #86
LUmBULtERA wrote: post #51

Earlier quoted context omitted.

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.

This argument ignores the cost of transmission and distribution, which are higher costs than the generation itself. And as electricity prices are driven down even further, T&D will come to dominate over energy generation costs. Few models account for this, but Christopher Clack made one, and the lowest cost energy path was a small amount of investment in distribution now, paired with massive deployment of solar on ho…

Unless every home is completely off the grid, you’re going to need to pay for most or the majority of that transmission and distribution anyway. Peak winter and summer I also would imagine many or most residential deployments aren’t going to cover their own need, unless they’re incredibly over built with massive batteries. In any case, I should check out your Christopher Clack reference.

Re: The rise of batteries in six charts

#129

Post by TOMDM »

chris_va wrote: post #71
tonymet wrote: post #54

Lithium Battery 0.5 kWh/kg Diesel 12.7 kWh/kg

You probably want kWh_e (electric) instead of kWh_t (thermal), and probably should include the weight of the engine/transmission. Diesel is better still, but not quite the same gap.

Also have to account for how many kWh are converted into motion.

Again, diesel still wins, but man is that gap closing.

Re: The rise of batteries in six charts

#130

Post by api »

tonymet wrote: post #101
api wrote: post #75

Earlier quoted context omitted.

Diesel is more like 3.175 (25%) due to the inefficiencies of small heat engines. You're throwing away like 3/4 of the energy as waste heat. Electric motors are >95% efficient and lithium batteries are in the high-90s percent efficient. Electricity is already low-entropy, whereas energy from burning petrol is high entropy and thus contains less useful work.

it's not waste half the year

True if you are cogenerating, but few people do that. Only a miniscule fraction of waste heat from a car engine is required to heat a car.

Tangent but: I've always wondered why home cogeneration never took off. Too bad we don't have gas water heaters and gas furnaces that generate electricity and dump the excess onto the grid and heat with the waste heat.

Even a low-efficiency thermoelectric generator would recover some useful energy that is otherwise kind of wasted.

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