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Lithium battery costs have fallen by 98% in three decades

economist.com

211–220 of 424 posts

Re: Lithium battery costs have fallen by 98% in three decades

#211
post #177

The article says that today a battery pack the size of a backpack and that weighs about 40kg, can power a house for a day. Is that really so? Would that be a normal house, being powered for an entire day? I find it hard to believe that battery would pack that much energy

Another anecdote: I rent a 50m^2 apartment. Electricity consumption for the apartment, averaged over trailing 12 months, is 4.5 kWh / day. This excludes: energy for stove top/oven (natural gas) and energy for hot water (paid for as part of rent, cannot see the details). Consumption for two people, including one person working from home full time. Relatively modern apartment that is warm enough in winter without activ…

That sounds reasonable. My house is about twice your size and so is my electricity consumption (8.8 kWh/day last billing cycle). Also doesn't exclude stove/oven/hot water as these are all powered by natural gas.

I was shocked by a few other comments saying 30 kWh/day. Is it because they use electricity to cook and heat water?

Re: Lithium battery costs have fallen by 98% in three decades

#212
post #71

This is important to keep in mind when you read articles and/or studies about how electric cars or wind or solar power is impractical. A lot of the data these studies use is just obsolete. Say you have an opinion piece in a news paper that says that electric cars will always be expensive toys for the rich. It relies on a scientific paper published in a technical journal 2 years ago. The scientific paper does not perf…

Are there many gains to be had on electric motors? I guess I sort of assumed those had seen quite a bit of optimization already.

Yes. A big improvement over the last few decades is rare earth magnets, which have reduced the mass, increased the power and efficiency. (Rare earth magnets in car motors can be and are recycled, FWIW.)

Additionally, the power electronics have improved a lot, too, and continue improving.

As others have noted, Tesla went from their induction motors (which use no rare earths) to a somewhat more efficient combination of switched reluctance and brushless DC motor using some rare earth magnets.

There are also various improvements to rare earth magnets. Magnetic energy density improves somewhat. Cooling schemes improve. Even alternatives to rare earth magnets (certain phases of iron or nickel, for instance) have been and are studied.

I think improvements in cooling schemes is a big part of future improvements. As well as reduction in eddy current losses through better litz wire, maybe playing with the grain structure of the conductor, etc.

Longer term, there's also the possibility of superconducting motors. Although that's mostly for larger scale applications, (near-)room temperature superconductors also have been demonstrated and folks are searching for methods to allow them to work at lower pressures.

So I think there's actually lot of room for improvements beyond low effort prototypes from big automakers. Tesla is doing really well with high efficiency powertrains. There's also the added dimension of integration with reduction gearing (as electric motors like to spin fast).

Re: Lithium battery costs have fallen by 98% in three decades

#213
post #119
post #86

Earlier quoted context omitted.

> Say you have an opinion piece in a news paper that says that electric cars will always be expensive toys for the rich. Well, you don't see poor people buying EVs that much. That's car manufacturer statistics, which I believe deserves a good degree of trust. In the market for new cars, poor people buy cheapest IC cars, but not cheapest EVs. I will take the point that middle class is now buying budget EVs, but you do…

> Well, you don't see poor people buying EVs that much. You don't see poor people buying new cars that much. Which for now is pretty much the same thing as not buying EVs, since almost all EVs on the road are relatively new. That's starting to change here in Norway. There's a decent amount of used EVs entering the second-hand market. And if you can deal with the short range it's definitely preferable to buy one, sinc…

> And I think cheap BEVs will be a HUGE benefit to poor people in the future, since it saves on gas and maintenance costs in the long term.

I’ve been wondering whether the opposite is true. We might find the cost of replacing the battery puts a floor on the price of old EV’s. I wouldn’t be surprised if we are coming to the end of bangernomics.

Re: Lithium battery costs have fallen by 98% in three decades

#214

Earlier quoted context omitted.

Collision avoidance, speed limiting, adaptive speed limiting, adaptive headlights, lane keeping, blind-spot warning, ISO-FIX anchors, far stronger pillars, reversing cameras, lane exit monitors, SOS buttons and GPS reporting, far more air bags, door-cyclist collision warnings, seat-belt pre-tensioning, some have pre-collision suspension raising, etc, etc, etc. I just went from a 2009 Land Rover to a 2020 Land Rover,…

How do you people leave out ESC - it saved my life at least once or twice and it’s obvious how well they work. What leaves me even more fumbled is how easily RWD Tesla’s spin out and crash with regen and snow. Take the gas pedal of and you’re going off roading. With normal car you’d struggle to even trigger ESC, let alone loose it.

My 2005 Honda has ESC (Honda calls it VSA-Vehicle Stability Assist) so it’s probably similar to ABS in these conversations: widely present and not a last 10-years’ addition. I think Toyota had it on all passenger models since 2004.

Re: Lithium battery costs have fallen by 98% in three decades

#215

Earlier quoted context omitted.

Hrmm, so the cost and performance is much the same, but it adds value by creating a new talking point for Tesla owners to harangue others with.

>Hrmm, so the cost and performance is much the same, but it adds value by creating a new talking point for Tesla owners to harangue others with. I know that hating on Tesla is a thing, but don't forget the higher torque, better efficiency, lower heat generation in the stator windings. And the fact that this type of motor first showed up in the Prius and Tesla made a better version of it. Yeah they're getting away wit…

I'm as big of a Tesla fan as any, but I'm both continuously impressed with how ahead-of-its-time the Prius was and continuously disappointed how lack-luster Toyota has been in pure electric cars. Toyota had like a decade lead on everyone else and just.... sat on it. Only invested in hybrids and hydrogen (which was and is a dead end).

Toyota could've gone all-in on pure electric cars (and better plug-in hybrids than they had at the time) a good decade ago but instead they continue to waste money on hydrogen.... Only now finally announcing pure-electric cars in the US: https://www.theverge.com/2021/2/10/22187113/toyota-electric-...

It's really sad. It's really bad for the climate that they just sat on the Prius drivetrain, which is 95% of the way to a pure electric car, for over two decades (it was released in 1997... it's 2021 right now!).

Literally, people have modded (i.e. added extra battery capacity) Priuses from 2003 to be pure electric even at highway speeds with the same motor and controller. They had everything sitting right there. It's incredibly frustrating.

Re: Lithium battery costs have fallen by 98% in three decades

#216
post #119

Earlier quoted context omitted.

> Well, you don't see poor people buying EVs that much. You don't see poor people buying new cars that much. Which for now is pretty much the same thing as not buying EVs, since almost all EVs on the road are relatively new. That's starting to change here in Norway. There's a decent amount of used EVs entering the second-hand market. And if you can deal with the short range it's definitely preferable to buy one, sinc…

> And I think cheap BEVs will be a HUGE benefit to poor people in the future, since it saves on gas and maintenance costs in the long term. I believe the same, if you race for the lowest cost possible, eventually an EV will be cheaper than the cheapest IC powered car for those exact reasons. ... But as I said above. Wuling MiniEV costs like $5500, which is cheaper than low-end Chinese petrol, or diesel engined sedans…

In part because the MiniEV has really low range (think first generation Leaf) whereas any IC car is gonna be like a Model 3 at least.

200 miles (on the EPA cycle) really is the minimum for a pure electric car IMHO. 250 miles, really. Otherwise it looks like less of a value than an IC car.

Re: Lithium battery costs have fallen by 98% in three decades

#217
post #126

Earlier quoted context omitted.

Surely you jest. What safety features on standard vehicles became indispensable in the past 10 years? Note: things like collision avoidance and adaptive cruise are still luxury features and the OG poster wouldn’t have bought those anyway.

Collision avoidance, speed limiting, adaptive speed limiting, adaptive headlights, lane keeping, blind-spot warning, ISO-FIX anchors, far stronger pillars, reversing cameras, lane exit monitors, SOS buttons and GPS reporting, far more air bags, door-cyclist collision warnings, seat-belt pre-tensioning, some have pre-collision suspension raising, etc, etc, etc. I just went from a 2009 Land Rover to a 2020 Land Rover,…

Also things like eCall (1) that became mandatory a couple of years ago without much fanfare: Fully automatic call/report to emergency services in a serious accident.

I think passive safety of modern cars has significantly improved too - they periodically up the ante on what it takes to get full scores in EuroNCAP for instance (2). A "top rating" car from 10 years ago would probably now be scarily-bad compared to the latest requirements that new models ace.

1 - https://en.m.wikipedia.org/wiki/ECall

2 - https://en.m.wikipedia.org/wiki/Euro_NCAP

Re: Lithium battery costs have fallen by 98% in three decades

#220
post #203

Earlier quoted context omitted.

Yes, using obsolete data from when tech was bleeding edge in 1999 to imply things about cost going forward is misleading. On the other hand using improvement over the same timeline, drawing a line on a graph and saying "look how X Y is gonna be in Z years" is the same exact type of stupid but pointed in a different direction. In 1991 lithium was highly immature technology and would take about a decade to make it into…

These are not the same kind of stupid. One makes the assumption that costs will always be the same, and the other makes the assumption that cost decreases are linear, or predictable. The former is much stupider.

Nope, it's the same thing: excess of confidence in predicting the future.
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