4680 cell lights

idleprocess

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Yeah, no joke.

I had two 6Ds when I ran movie theatres here in Miami, for AMC.

They were intimidating back then.

Skull crushers, I called them.

Chris

A friend of mine that used to hang out with bouncers claims they can't properly recognize a 5/6D maglight without - ahem - rust stains on the head.
 

orbital

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+


Not your grandmas tactical : blind em & then a solid attitude adjust.
:dedhorse:



^ substitute the horse for some *******
 

orbital

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Wouldn't you want 40~60V for a ebike?
because then you can use a lower KV motor that draws less Amps to make your watts. (lower Amp draw will give longer runtime)

46800 cells may be rather big, to have enough of them in series, to get at least 40V on a bicycle.
 

fivemega

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Just imagine a battrry pack of like this (1:24 minute) but 8 cells inside each oval bar of bike triangle frame and two of them will make 16 series cells. (16x3.7=59.2V)
It's also possible to custom made carbon fiber triangle frame box. In this case, battery pack can be replaced when needed.
We are getting close to two seatter Ebike with long range.
 

orbital

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Just imagine a battrry pack of like this (1:24 minute) but 8 cells inside each oval bar of bike triangle frame and two of them will make 16 series cells. (16x3.7=59.2V)
It's also possible to custom made carbon fiber triangle frame box. In this case, battery pack can be replaced when needed.
We are getting close to two seatter Ebike with long range.

+

Like the idea.

_____

Last summer I was on my '02 Honda and rode up next to an older woman on what looked like an Ebike. She just just cruzzin down the street by this soccer field area.
She was going maybe 15mph.
While riding next to each other, I asked her if that was electric, she said Yes. Then I asked if it was fun,, she smiled & laughed a bit & said 'Yes it is' :grin2:

Ebikes are here to stay.
 

redorblack

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I'd like to get my hands on 19or 38 of them for a 72v 25 or 50AH pack for my electric Vespa style scooter. I converted it a few years back from lead acid batteries that were completely fried and melted together when it was gifted to me. I replaced those with an Ebay 72v 50Ah LiFePo4 pouch cell pack that worked great for a few years... then a cell lost capacity on me and I took it apart and it's been sitting in my kitchen since. Figuring out how to build a pack out of the new Tesla cells would be fun and exciting... the biggest deal is the massive current capacity that they'll be handling with much much lower resistance internally. The tabless design dramatically reduces the distance current travels through the cells. I would love to see some sort of C rating from Tesla or anyone that has gotten their hands on a sample. Tesla is so far ahead of the game with their chemistry and thermal management systems that the Model S and X Plaid vehicles are still using 18650 cells... and putting down 1020 HP without overheating issues.
 

3_gun

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I doubt this size will ever be a base point of an EDC but for GP lights, lanterns, S&R, bike & headlamps running a remote battery pack, size becomes much less of an issue. Still those together are not a huge market segment but there is a market. Doubt it will be a direction I'd be going to but less than 2 years ago I'd never heard of a 18650 or 21700 & was using a AA light for EDC. AA still has its place but most of my lights are 18650/21700 based now.
 

sirpetr

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I doubt this size will ever be a base point of an EDC but for GP lights, lanterns, S&R, bike & headlamps running a remote battery pack, size becomes much less of an issue. Still those together are not a huge market segment but there is a market.
Absolutely agree. I am quite sure Tesla 4860 battery will never get to the public.
 

degarb

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A three cell flashlight can use a 92 percent efficient switching buck driver, while a single cell light can only use a 70 percent efficient linear driver.

This means that you can only get 7000 mah out of a 10,000 mah single cell, and 9200 mah out of 3 cells with a good buck driver.

If u were to design a 3 watt light, it would be the difference of over 2 hours and make all the difference in the world between a reasonable full day of runtime and needing to feel around in the dark for 2 hours. On a 3 man crew, it would mean up to 200 hours lost per year swapping out cells. A lone wolf, it would mean maybe 5 minutes over 300 days, or about 50 hours lost per year. .... Now, for tool belt battery packs, maybe...
 

idleprocess

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This means that you can only get 7000 mah out of a 10,000 mah single cell, and 9200 mah out of 3 cells with a good buck driver.
I'm at a real loss why so many media outlets have reported 9-10Ah capacity for the 4680 cell - such a tiny capacity for that much cell volume would result in a crippling hit to range for a BEV. The 4680 cell will likely clock in at around 25Ah if its energy density is in the neighborhood of the 18650 and 21700 cells Tesla is presently using:
1645124385712.png


For real-world driving there's no improvement to peak current limits that will make up for energy density that's about a third of present formfactors. At the drag strip, maybe, but the Model S Plaid's limits in that realm seem to center around traction rather than power delivery.
 

orbital

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Tesla went with the 4680 only because it can charge faster, nothing else.

That is the biggest factor in EV,,, how fast can it recharge.

{46mm x 80mm}
 

idleprocess

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Tesla went with the 4680 only because it can charge faster, nothing else.

That is the biggest factor in EV,,, how fast can it recharge.
All the features that Tesla gushed about in the 4680 do indeed speak to greater current-handling characteristics. But that factor cannot come at a significant hit to energy density.

All the EV owners I've spoken to do the overwhelming majority of their charging overnight using the equivalent of a dryer outlet at home. 8 hours at the ~7.2kW you can reliably get from a dryer outlet (30A x 240V) is plenty of juice for nearly all daily driving: 57,600 Wh / 320 Wh/mi (Model S nominal, rounded up) = 180 miles' nominal range. Given average daily driving for most falls far short of this number most will start each day at a full charge using a 'slow' 240V charger. Fast charging is first for road trips where taking ~30 minutes to recover to ~80% is acceptable, second for convenience charging running errands and there happens to be a fast charger nearby. There are certainly some folks who rely on fast charging for their EVs as the sole means of 'filling up', but they're presently a small minority of the EV market.

In Tesla's case, the ranges they're quoting for the Cybertruck (rumored to be the first vehicle with the 4680 cell) don't allow for energy density that's a third of 18650/21700. Similarly, Tesla has spoken to transitioning Model 3/Y to the 4680 and there's definitely no margin to reduce capacity to a ~third and maintain the base 267- /318-mile ranges.
 
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