Earlier quoted context omitted.
It doesn’t go out where I live, but you could instead get a diesel generator and not have to worry about utilities
That's not what I meant. Eventually, it will go out for the entire planet. It is not an unlimited resource. Then what?
The price of lithium-ion batteries has declined by 97% in the last three decades
181–190 of 330 posts
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#182Earlier quoted context omitted.
Don’t forget to account for the differences in engine and drivetrain efficiency. a gasoline engine gets way less of the gasoline's energy to the wheels. The engines of today are 30-40% efficient iirc, and then you lose more in the tranmission, differentials, etc. Electric motors are ~80-96% efficient and there is less transmission losses involved after that too. also energy density of cells and packs continues to imp…
Source?
Besides what the other guy posted, see how far you can drive per unit of energy.
A gas car getting 26 mpg -> 26 miles from 33.41 kWh of energy -> 1285 Wh/mi
A Tesla Model 3 getting 353 miles from a 75 kWh battery -> 212 Wh/mi
That's a 6x advantage.
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#183Earlier quoted context omitted.
> $2000 for a 30kWh home battery backup? Who wouldn't get one? Because it would be a lot more than $2k to get put it in your home. If you do the math on a Tesla powerwall, the raw cost of the battery should be right around $2k too. But it actually costs more like $8k per powerwall.
That's for a few reasons. Competition is low. There are only a few players in the home battery space and they are similarly priced. Demand is high. Even with the higher price, the wait list to get a powerwall is more than a year out. My expectation is a few things happen over the next 9 years. I expect that battery production ramps up to a high degree. I expect that the EV market will eventually be saturated With tho…
Battery powered trains seem really unlikely to me. It's hard to imagine a situation where it's cheaper to do a battery powered train than a train track that supplies power (aka how most subways work).
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#184Earlier quoted context omitted.
Lead acid batteries can emit fumes, so they are not useful in the same settings as li-ion batteries.
Aren't most lead-acid batteries sealed? The one in my mobility scooter certainly is.
I imagine many are. But in small spaces with poor ventilation (e.g. vehicle interiors) that might not be enough. The sealed batteries still have a vent for the gas to leak (in a controlled manner).
https://electronics.stackexchange.com/questions/175649/are-s...
But besides that, li-ion batteries have more energy per weight, are more efficient at storing energy, and can be discharged to a farther level without negatively impacting the battery.
Sorry for the annoying popups, this is the best source I could find: https://news.energysage.com/lithium-ion-vs-lead-acid-batteri...
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#185AAs with 500 mAh capacity and 50 mA charging was a marvel at the time. My greatest invention was that I connected bicycle dynamo directly to a small windmill and upped the voltage with diode ladder. It gave only 50 mA, but alas, that was what those batteries were rated for. Wind blows 24/7 so it was remarkable if you compare with solar panels. https://www.youtube.com/watch?v=XYorx9C-OEE&t=26s
Started to wonder why there is a switch on the charger box. Finally dawned on me: You cannot have the LED blinking and using 20 mA when your total energy production is 50 mA.
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#186Earlier quoted context omitted.
> 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. My expectation is that with climate change, unreliable electricity is going to affect a lot more places. The polar vortex that knocked out the Texas grid is likely to be a more frequent and more extreme event. ACs runni…
A 1KWh battery is affordable now using off-the-shelf lead acid batteries. There is no advantage using Lithium batteries (at present) as size and/or weight is not critical for domestic applications. The whole point of the discussion is that Lithium is still not cheaper than Lead acid.
Lead acid batteries suck for more reasons than just their size and weight. One major disadvantage is that the faster you discharge them the less of their charge you will actually recover[1]. Additionally, discharging them below 50% capacity significantly reduces their life in terms of total cycles (even for cells rated for "deep cycle" operation)[2][3] so you need to oversize your battery system to get the same effective capacity if you want your cells to last. Lithium batteries suffer from neither of those drawbacks.
If those weren't enough, even when treated well (not discharged too deeply) lead-acid batteries don't last for as many discharge cycles as lithium iron phosphate cells. If you do the math, for batteries cycled daily modern LiFePo batteries are about the same TCO as lead-acid despite the higher up-front costs because the lithium batteries will last significantly longer and you don't need to buy as much absolute capacity for the same effective capacity. Here's a good presentation on this: https://www.youtube.com/watch?v=BRqRDZh74F0
[1] http://omahamakergroup.org/2015/05/14/battery-derating-and-c...
[2] https://www.pveducation.org/pvcdrom/lead-acid-batteries/char...
[3] https://www.solar-electric.com/media/wysiwyg/cyclelife2.gif (Graph shows cycles (y-axis) vs average depth of discharge (x-axis) for a typical "deep cycle" lead-acid battery. Note the y-axis is logarithmic.)
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#187Although Li-Ion cells are getting cheaper and cheaper every year, it still is worth salvaging the good ones from depleted laptop battery packs. When a laptop battery pack is gone it's almost always the case of one, max two, 18650 elements that failed, not the whole pack. I've built some good power banks using empty shells (very cheap on Ebay, Aliexpress etc.) and fitting inside the good cells salvaged that way. They…
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.
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#188Earlier quoted context omitted.
That's for a few reasons. Competition is low. There are only a few players in the home battery space and they are similarly priced. Demand is high. Even with the higher price, the wait list to get a powerwall is more than a year out. My expectation is a few things happen over the next 9 years. I expect that battery production ramps up to a high degree. I expect that the EV market will eventually be saturated With tho…
Battery powered trains seem really unlikely to me. It's hard to imagine a situation where it's cheaper to do a battery powered train than a train track that supplies power (aka how most subways work).
The rest of the world doesn't live in high density built up areas. Many small crops farming trains in rural areas can not and will not be allowed to run power through the tracks in above ground situations.
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#189Earlier quoted context omitted.
That's for a few reasons. Competition is low. There are only a few players in the home battery space and they are similarly priced. Demand is high. Even with the higher price, the wait list to get a powerwall is more than a year out. My expectation is a few things happen over the next 9 years. I expect that battery production ramps up to a high degree. I expect that the EV market will eventually be saturated With tho…
Battery powered trains seem really unlikely to me. It's hard to imagine a situation where it's cheaper to do a battery powered train than a train track that supplies power (aka how most subways work).
I can think of a few usages for it.
Batteries could get a train up to cruising speed requiring a smaller train engine and less fuel.
Batteries could save on line expansion, instead of installing a 3rd rail for the whole line, they could go a 3rd rail every 50 miles for 10 miles.
I agree a 3rd rail would be cheaper in the long run. Batteries could help bridge the gap.
Re: The price of lithium-ion batteries has declined by 97% in the last three decades
#190Earlier quoted context omitted.
Well, the technology on 12v car batteries has continued to advance. /s It’s ridiculous how expensive they’ve become. More so when there is no R&D costs associated. Manufacturers simply slap on a different name and sell it at a premium.
Car batteries are heavily dependent on the price of lead. You can look at the 25Y lead price chart here: https://tradingeconomics.com/commodity/lead So much of the difference comes from that. Though there has been quite a bit of development on lead acid batteries, and the last 10-15 years have actually been quite exciting. The focus is more on the deep cycle/energy storage side of them, as opposed to car batteries (w…
I appreciate the long form response.