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Tesla battery researcher unveils new cell that could last 1M miles

electrek.co

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Re: Tesla battery researcher unveils new cell that could last 1M miles

#61

Post by falcolas »

Reason077 wrote: post #25
falcolas wrote: post #20

Earlier quoted context omitted.

Nothing here indicates a discharge rate. I'm having trouble finding the actual wattage produced by these cells over the 6 hour discharge time. Also, 6 hours is a longer than the current Tesla will run full charge at highway speeds (350 mile range, 75 mph ~= 4.5 hours). Plus, the current tesla can be re-charged and continue to operate, conditions I don't see mentioned. If it is similar to existing batteries though...…

"Nothing here indicates a discharge rate." In battery terminology, and this paper, charge/discharge rate is referred to as "C". Charging or discharging at 1C means a battery would be fully charged/discharged in 1 hour. A 100 Wh cell discharging at 1C would produce 100 W. Likewise, at 3C it would take 20 minutes and produce 300 W. At C/3, it would take 3 hours.

That doesn’t give us any information on the capacity of the cells. Once we know the MAh of the cells, that gives us the output amperage, but without the capacity (or an amperage/watt value to derive the capacity), it’s a useless value.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#62

Post by nwallin »

guerby wrote: post #29

Two things missed by the electrek piece: - The article is CC-BY and downloable without scribd horrible UI: http://jes.ecsdl.org/content/166/13/A3031 PDF direct http://jes.ecsdl.org/content/166/13/A3031.full.pdf HTML direct http://jes.ecsdl.org/content/166/13/A3031.full.html - In the conclusion the authors mention: Full details of these cells including electrode compositions, electrode loadings, electrolyte compositio…

> Full details of these cells including electrode compositions, electrode loadings, electrolyte compositions, additives used, etc. have been provided in contrast to literature reports using commercial cells. This has been done so that others can re-create these cells and use them as benchmarks for their own R+D efforts be they in the spaces of Li-ion cells or “beyond Li-ion cells”.

That's incredible.

Normally I walk into these wunderbattery threads expecting to heap reproducibility scorn (we're still waiting for solid state glass batteries, and will in all likelihood be waiting forever) but pathways to reproducibility aren't something I'm used to in battery vaporware.

I'm actually excited for battery tech, which seems weird given all the disappointment over the previous decade or two. Feels like being excited for another cancer cure in mice.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#63

Post by inflatableDodo »

hwillis wrote: post #42
Zenst wrote: post #31

Earlier quoted context omitted.

Will we end up with seasonal battery's? Many already accustomed to switching tiers in winter. Whilst temperature management of batteries would cover many aspects, some locations a better tuned battery would make it more efficient overall perhaps. EDIT [s/riers/tires/;sleep]

Very unlikely. Winter batteries aren't a huge problem as long as you are gentle until the pack is warm. Hot batteries are more of an issue, as they don't really like temperatures above 90-100 F. Keeping the battery at half charge helps reduce that damage a lot. Ultimately if you live in a hot climate the best thing to do is have a cool garage. The higher heat while out and about is not an issue, just the constant lev…

Was wondering about if you could put a liquid coolant loop from the battery to the charging socket on the car, then have a heat exchanger in the plug and run water to and from it using a jacket round the cable, so you can have a rapid charge that also helps heat your bath water.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#64

Post by BubRoss »

DuskStar wrote: post #52
BubRoss wrote: post #51

Earlier quoted context omitted.

That's assuming that batteries would stay the same price while currency inflates.

It's assuming that the item you're purchasing would maintain the same real price. If it cost $10 to start, and after 10% inflation the battery now costs $11, this holds. (Well, it holds if you have some way to beat inflation with safe returns. US government bonds often but not always meet this requirement) In the case of batteries specifically, I think it's likely that prices drop even without adjusting for inflation…

What you are saying doesn't even make sense. The original comment was that a battery that lasts 5x as long costs 1/5th the price over time, and your hypothetical is buying a much cheaper battery for some reason. There is no reason to play semantic games with the time value of money, it is clear what the original person was saying.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#65

Post by NotSammyHagar »

manmal wrote: post #24

This is very exciting. BEVs that were made before 2016 (I think that was when the last breakthrough trickled down to BEVs in the market) typically had a battery lifetime of about 70k miles or maybe a bit more before reaching 70% capacity. Fast-charging regularly might reduce capacity by several percent points within a few hot summer months. Basically, you bought a car for €30k and it might become useless 5-7 years la…

My 2012 tesla model s didn't seem to follow this. At 5 years old it had barely less capacity than original capacity. Est range went from 275 to 265. If you follow teslas, there are many (100s) of people with great than 100k of miles. The battery heating and cooling system was crucial. The leafs do suffer from serious problems. I wasn't aware they weren't charging up the battery. When speaking of evs, you really have to discuss two worlds, tesla and everyone else.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#66

Post by manmal »

NotSammyHagar wrote: post #65
manmal wrote: post #24

This is very exciting. BEVs that were made before 2016 (I think that was when the last breakthrough trickled down to BEVs in the market) typically had a battery lifetime of about 70k miles or maybe a bit more before reaching 70% capacity. Fast-charging regularly might reduce capacity by several percent points within a few hot summer months. Basically, you bought a car for €30k and it might become useless 5-7 years la…

My 2012 tesla model s didn't seem to follow this. At 5 years old it had barely less capacity than original capacity. Est range went from 275 to 265. If you follow teslas, there are many (100s) of people with great than 100k of miles. The battery heating and cooling system was crucial. The leafs do suffer from serious problems. I wasn't aware they weren't charging up the battery. When speaking of evs, you really have…

Indeed, Tesla has always had a superior BMS, and I keep hearing that they have a custom electrolyte or something that Panasonic uses for their cells? They seem to get 2-3x the lifetime out of similar cells. The Leafs don't have liquid cooling, and that's the only reason why I won't buy one - it's both bad for battery life, and fast-charging (Leaf owners call it Rapidgate).

Re: Tesla battery researcher unveils new cell that could last 1M miles

#67

Post by manmal »

MrRadar wrote: post #32
manmal wrote: post #24

This is very exciting. BEVs that were made before 2016 (I think that was when the last breakthrough trickled down to BEVs in the market) typically had a battery lifetime of about 70k miles or maybe a bit more before reaching 70% capacity. Fast-charging regularly might reduce capacity by several percent points within a few hot summer months. Basically, you bought a car for €30k and it might become useless 5-7 years la…

I think that was mainly due to early EVs having low battery capacities in general (because batteries cost a lot more then) so daily commuting would cycle them much more deeply than current high-capacity models. This 2017 article[1] shows battery life data for hundreds of Tesla Model S's (which have always come with large-capacity batteries). One of the highest-mileage cars in their data pool had just over 220k km (13…

The difference in lifespan that I mentioned occurred in packs of similar sizes, for all manufacturers but Tesla. Tesla is in its league when it comes to battery lifespan.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#68

Post by generatorguy »

deepnotderp wrote: post #48
generatorguy wrote: post #17

Earlier quoted context omitted.

Who would have thought that microchips would become so cheap? And they are built on silicon crystals. The economies of scale for batteries for cars, phones, computers, will kick in in a way that they don’t for aerospace. Car or phone battery tech will end up in airplanes!

The amount of silicon in a microchip is tiny. By contrast, single crystal metal alloys for modern turbo fans comprise a significant portion of their cost.

well microchips are small compared to turbo fans. Turbo fans are also hollow and inflated via some crazy trade secret process which the Chinese haven't figured out yet, hence them not making their own engines.

So the anode or cathode on a battery, or even a whole AA size battery cell, is more on the scale of a microchip than a turbofan blade I think. plus the battery won't have to be subject to the same QA process of x-raying to ensure there are no microscopic cracks or defects. If one cell in your battery pack isn't as good as the rest it will just be managed around instead of subjecting all the cells to insane QA.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#69

Post by DuskStar »

BubRoss wrote: post #64
DuskStar wrote: post #52

Earlier quoted context omitted.

It's assuming that the item you're purchasing would maintain the same real price. If it cost $10 to start, and after 10% inflation the battery now costs $11, this holds. (Well, it holds if you have some way to beat inflation with safe returns. US government bonds often but not always meet this requirement) In the case of batteries specifically, I think it's likely that prices drop even without adjusting for inflation…

What you are saying doesn't even make sense. The original comment was that a battery that lasts 5x as long costs 1/5th the price over time, and your hypothetical is buying a much cheaper battery for some reason. There is no reason to play semantic games with the time value of money, it is clear what the original person was saying.

My point was that as lifetimes get longer, value does not scale linearly. Would you pay 1000x as much for a battery bank that would last until 12019, or would you assume that it would be made obsolete at some point over that period? Maybe we've all moved to fusion, and grid-scale storage is useless. Or perhaps prices decreased by 10x over the next 20 years, and so getting a 20 year battery + a 9980 year battery would only cost 2+998/10=101.8 times as much as the original 10 year instead of 1000 times.

Time value of money is important, and IMO would be enough on its own. But opportunity cost from excluding future improvements matters too - and given the improvements in battery tech over the past decade, one that would certainly be relevant over the next five decades.

Re: Tesla battery researcher unveils new cell that could last 1M miles

#70

Post by Reason077 »

falcolas wrote: post #61
Reason077 wrote: post #25

Earlier quoted context omitted.

"Nothing here indicates a discharge rate." In battery terminology, and this paper, charge/discharge rate is referred to as "C". Charging or discharging at 1C means a battery would be fully charged/discharged in 1 hour. A 100 Wh cell discharging at 1C would produce 100 W. Likewise, at 3C it would take 20 minutes and produce 300 W. At C/3, it would take 3 hours.

That doesn’t give us any information on the capacity of the cells. Once we know the MAh of the cells, that gives us the output amperage, but without the capacity (or an amperage/watt value to derive the capacity), it’s a useless value.

This information is given in the paper. Look for terms like capacity (mAh), specific energy (Wh/kg), and energy density (Wh/L).
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