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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

#41

Post by hwillis »

rat9988 wrote: post #34
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.

Are charge and discharge rate usually equal?

No, but it is common to treat them as if they were. It depends on the chemistry as some are worse, but charging is slightly rougher than discharging.

During charge the lithium ions need to intercalate into the graphite anode, which is slower than the reverse.

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

#42

Post by hwillis »

Zenst wrote: post #31
hwillis wrote: post #30

Earlier quoted context omitted.

It is not. This is a fairly conventional cell, with a different crystal structure for one of the ingredients, and a tweaked mix of liquid electrolytes. The most important part of this paper is that they actually prove that optimizing for cycle and calendar life can have such incredible effects.

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 level of high heat. The only people who would get a real benefit from high temperature batteries are those without. Batteries are much more expensive than tires and the market is smaller.

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

#44

Post by FooHentai »

hwillis wrote: post #40
alanh wrote: post #26

Earlier quoted context omitted.

what is 'state of charge swing'?

I think it is referring to the fact that it is ubiquitous to leave some amount of reserve so that the battery is never fully charged (100% SoC) or discharged (0% SoC). This formulation is capable of going the full 0-100%, while most formulations will last significantly longer if they don't do that.[1] In that graph, charging to 75% and discharging to 25% gives you about 3x more life than from 25%-100%. NB that most l…

24kw leaf battery is an example of this with user stats seemingly bearing it out. Charge it to 80% each time, you can expect 3000 cycles before it's spent (drops below 85% of original capacity). If you charge to 100% each time, you'll only get 1000 cycles.

3-4 years versus 8-10 years use makes a big difference.

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

#45

Post by DuskStar »

hwillis wrote: post #28
Osiris30 wrote: post #21

Earlier quoted context omitted.

Would this be a correct summary of the paper? 1) eliminates Cobalt 2) improves energy density (more range) 3) faster charge rate 4) less SOC (state of charge) swing, meaning less cost & weight 4) 5x longer lifespan

1) 532 is not a new chemistry. It's not even the lowest cobalt chemistry; there's 511 and 811 beyond that (811, or 80% nickel, 10% manganese, and 10% cobalt, is not yet technically feasible). 2) Range is decreased. 532 has lower energy density. 3) Maybe..? But nothing truly significant. The additives in this chemistry mean a lot of heat gets generated during charge/discharge. Heat is the limiting factor during charge…

> since a battery that lasts 5x as long costs 5x less.

This is only true if there is an inflation-adjusted discount rate of 0%, which is unrealistic even in this era of low interest rates. Adjusted for inflation, paying $10 now and again at years 10, 20, 30 and 40 is better than paying $50 up front would be. (By adjusted for inflation, I mean that the $10 you pay in 10 years might actually be $11, but still $10 in 2019 dollars)

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

#47

Post by ianai »

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…

It’s probably worth it for locations that see extreme heat throughout the year though. Phoenix, LV, etc would probably be cheaper markets at scale with specially engineered batteries.

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

#48

Post by deepnotderp »

generatorguy wrote: post #17
sandworm101 wrote: post #8

>> The new battery tested is a Li-Ion battery cell with a next-generation “single crystal” NMC cathode and a new advanced electrolyte. If this is anything like growing single-crystal parts for aircraft, it won't be cheap. The real question should be whether these new battery modules will last twice as long while remaining less than twice as expensive. >> Controlling the charge to less than 100% state-of-charge also h…

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.

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

#49

Post by crispinb »

jokoon wrote: post #46

I'm sure batteries would be immensely better if the military would spend money into research towards better batteries.

Militaries don't have magic, they just tend to have lots of money. Foreigners' deaths are profitable for capitalist sociopaths, and good for election prospects of political sociopaths.

Now, divert government money from death industries to battery research, and we'd be talking.

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

#50

Post by surewhynat »

ianai wrote: post #27

Can anyone tell whether this is a solid state electrolyte? I’m still hooked on what I saw in that Netflix documentary where the guy was able to cut and puncture the battery without combustion. Also seemed capable of being much more dense.

which documentary was that?
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