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The price of lithium-ion batteries has declined by 97% in the last three decades

ourworldindata.org

281–290 of 330 posts

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#281
post #3

This is really cool, but could anyone familiar with the domain estimate how far we are along the S-curve? I.e. it took a long time for things to ramp up, then they accelerate really quickly and then they slow down again. Think Moore's Law, which is dead now. What would be the price estimate for 2030, for example. I think we're now around $100 per kwh (or something like that), what should we expect for 2030? $60? $20?

Moores law isn't dead:

https://ourworldindata.org/technological-progress

You probably mean Dennard scaling is dead. The breakdown was around 2006.

https://en.wikipedia.org/wiki/Dennard_scaling

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#282
post #267

Earlier quoted context omitted.

And boats!

Are there any electric boats yet? Especially curious about the feasibility for shipping boats. The density seems to be less of a concern there.

There are several electric ferries in use in Norway and Denmark.

Example https://www.visitaeroe.com/ellen

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#283
post #271

Earlier quoted context omitted.

Why not replace plane travel with hyperloop? Airplanes are high polluters, pay little taxes (none on fuel) , require massive bailouts and the only US civilian airplane maker is a soon to be anachronism... On the other hand...the infrastructure requirements for a cross coast hyperloop venture...especially if impulsed by government would resolve a lot of things...besides couldn't it be used for cargo..Amazon might be i…

> Why not replace plane travel with hyperloop? You can’t replace a reliable mode of transportation with something that doesn’t exist yet. Even when it’s ready, it’d take decades. Political powers are reluctant to commit to something that’s going to take longer than their careers. Then again, you don’t even need hyperloop. Germany has 250 km/h trains, those are more than enough for many routes.

Lots of countries have 330 km/h trains, and Japan is hoping to open the Chūō shinkansen within the decade, running at up to 500 km/h.

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#284
post #62

Earlier quoted context omitted.

> $2000 for a 30kWh home battery backup? Who wouldn't get one? Very few of the people that would currently benefit from a domestic backup battery could afford $2k, and most of the people who do have $2k to spare don’t live in places with unreliable electricity. The overlap isn’t zero, but… for example, I visited Kenya with an ex of mine, we met a local friend of hers, that friend would’ve benefited from a more reliab…

1. Here in CT with our abundance of trees, a large fraction of the state loses power for the better part of a week every couple of years when a windstorm comes up the coast. 2. Batteries need not just be for power outages. Net metering, granular demand-based energy pricing, etc are all reasons to get a battery for your house.

Value for money is not my argument.

I’m just saying loads of people for whom it would provide benefit don’t have $2k spare money to invest.

To put a different spin on it: the price point for the cheapest consumer unit should be way lower than that… unless you force landlords to install it at their own cost (as a landlord myself: a $2k legally mandated expense would not be happy fun times, but I could and would suck it up).

And even then, you’re still thinking in terms of the richest economies, and first quartile incomes in developing nations would struggle with $25 backup batteries let alone $2000.

One belief of mine which is shifting from all the replies I’ve been getting, is that I’m increasingly surprised how bad everyone’s telling me that America’s fundamental infrastructure is.

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#285
post #235

Earlier quoted context omitted.

Energy density is a meaningless measure for cars. $ per mile isn't. If you have a heavier battery, you just need a bit more of it to drive the same amount of miles. It just boils down to cost in the end. You can also trade weight for mileage and have less battery. That lowers the cost and improves the mileage. Apparently Tesla has pushed internal cost per kwh of storage below 100$ now. That price is going to drop fur…

Range matters. My current Volvo V40 can, at highway speeds, go for 1100km on a full tank of diesel. There is no electric car at a similar price that can go farther than 500km, in practice I'd be shocked if it went more than 400km. I'd want range to be at least 80% of that of the diesel before I switch.

How often do you drive 880km in one go?

You've got to remember that with an EV, you start every day with a full 'tank'*

(* as long as you've got somewhere to plug it in overnight, which is a problem in some places, granted)

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#286
post #267

Earlier quoted context omitted.

And boats!

Are there any electric boats yet? Especially curious about the feasibility for shipping boats. The density seems to be less of a concern there.

These guys are doing some great things here in Seattle: http://purewatercraft.com

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#287
post #235

Earlier quoted context omitted.

Range matters. My current Volvo V40 can, at highway speeds, go for 1100km on a full tank of diesel. There is no electric car at a similar price that can go farther than 500km, in practice I'd be shocked if it went more than 400km. I'd want range to be at least 80% of that of the diesel before I switch.

How often do you drive 880km in one go? You've got to remember that with an EV, you start every day with a full 'tank'* (* as long as you've got somewhere to plug it in overnight, which is a problem in some places, granted)

Not often, but we're not going to buy 2 separate cars, 1 for regular trips and one for road trips.

Range anxiety is a thing, especially since the "failure mode" is really bad. Super chargers are really rare compared to gas stations and if you run out of battery, with regular charging it takes 10 hours to charge.

Maybe 880km is too much, but for sure I'd want 60% (so 660km) + something extra, maybe 50-80km, to not feel anxious when driving long distance.

Plus overnight charging is unfortunately still a problem.

I personally think that for me (and I guess many others), the next generation of EVs or maybe the facelift for the current generation should be really close to what I want. By next generation I mean that many EVs are/will be launched soon (so 2020/2021/2022), in the car world a generation is usually around 7-9 years (so 2027-2031), and a facelift is done usually mid-cycle (so probably 2025-2026).

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#288
post #44

Earlier quoted context omitted.

Does this come with a “know what you are doing” caveat? I’d be scared of creating an electric firelighter in the process. Also assuming money is no object. Is it as good for the environment to recycle the old battery and buy a refurbed one.

> Does this come with a “know what you are doing” caveat? Yes, and I'll suggest that a disturbingly large fraction of the people doing this on YouTube don't know what they're doing, and are being brutally unsafe with the batteries, even if it works. I've done battery pack rebuilding semi-professionally for a few years (I was rebuilding ebike packs for most of North America from about 2015 to 2018), and the people scr…

Thank you so much for sharing your experience. It's valuable.

Do you know any best practices about who does this right, and how it can be done both safely and economically? If necessary with automation and large scale.

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#289

Earlier quoted context omitted.

Parallel cells will automatically balance as the charged cells feed the discharged cells. There is absolutely no point in trying to balance them.

There is. Preventing overcurrent, as the automatic balancing process you are describing can be over hundred times faster than the charging rates the batteries are rated for.

You both are right, but there is a caveat: the cells internal resistance.

Connecting cells in parallel is inherently safe if done when they're brought all at the same level; from that moment on they won't charge or discharge across each other because the current draw will always bring them at the same voltage, therefore having zero current from cell to cell. The problem is however when one or more cells degrade with age, therefore we have more efficient cells in parallel with less efficient ones. That is not a problem safety wise as well, because as before they'll always be at the same potential, but should their degradation change their internal resistance to a point it's a lot higher than their normal one, then we would have the good cells with lower internal resistance sustaining the most current during charge or discharge, and that could be dangerous. To avoid situations like that one, never implement charges faster than the one that could be sustained by a single cell. Let's say one 2Ah cell can be safely charged at 2C max, that is, 4 Amperes, if we build a pack of 3 of those cells in parallel we would be tempted to charge them at 6C, that is 12 Amperes, which would work in a new pack with all cells that equally balance the current. But if (when) one or two cells degrade their internal chemistry increasing their internal resistance, we'd be left with the remaining good cell(s) drawing the most current, which will largely exceed their individual rating, overheating them and potentially making them explode (that's also when individual cell protection make sense). There's actually a case in which a cell chemistry is so degraded that it can't only store the same amount of current, but also the same voltage, and this could be a problem in parallel packs, but the battery performance drop should have warned us a lot before this happens.

So, all we need is to keep the charge current as low as the current sustainable by a single cell, and we're safe. Slow charging also benefits the overall cells life. Don't worry about connecting unprotected cells in parallel, as they balance themselves: all laptop batteries have balanced series of unbalanced parallels. For example, a 6 cell pack contains is arranged as 2p+2p+2p (2 cells in parallel in series with 2 cells in parallel in series with 2 cells in parallel) while 9 cell packs use 3 cells parallels; series cells are balanced through the BMS, but parallel cells will self balance. What is important is to keep series groups balanced and protect against excessive voltage and charge/discharge current.

Re: The price of lithium-ion batteries has declined by 97% in the last three decades

#290
post #224

Nice that the cost has come down. Unfortunately, that which makes electric cars and planes feasible, namely energy density (Wh/litre) and specific energy (Wh/kg), has not improved that rapidly. The article mentions a factor of 3.4 over 30 years for energy density, ie 4% p.a., or doubling every 17 years. I think electric aircraft need another doubling or two in specific energy to become feasible, so another few decade…

If one looks at the Wh/kg of the very best li ion batteries right now (about 250Wh/kg) and then compares it to the Wh/kg in avgas or jet a or diesel, it's nuts. Even if you lose 40-60% to waste heat. The amount of energy contained in those fuels is ridiculously dense by comparison.

You must also account for the engine / motor / transmission / drivetrain / fuel tank weight difference you can't just look at fuel weight alone.

In ground vehicles the weight of the engine and transmission and running gear is more than an electric motor and controller with much simpler usually single speed transmission and drivetrain especially diesel. Then there is structural batteries where the structure of battery helps replace some of the vehicle structure reducing wieght. This is why electric cars are starting to be competitive.

Planes are somewhat different modern turbine engines are relatively light for their power output and there is not much of a transmission on planes, usually variable props instead and fuel tanks are sort of structural. Although having many multiple props driven by small electric motors can have advantages which would be complicated and heavy to do with a drivetrain in a plane. Still electric planes are far from practical IMO.

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