ev battery packs must resist to some impactor tests such like a pole . multi cells are just safer.
also multi cells in series are required to reach high voltages necessary for the car motor(s) to run.
think that Tesla is running on 400V motor(s)
That’s not what he’s talking about, he’s talking about cylindrical vs prismatic cells.
Lipo packs used in phones and laptops are prismatic pouches in the shape of flat rectangles, 18650s and 21700s are cylindrical lithium ion cells.
It’s just a different shape.
You can put multiple lipo packs in series just like with cylindrical cells to get high voltages.
Lipo and 18650 isn’t a high or low end laptop thing, it’s a thin versus thick thing. There are plenty of thick high end laptops that have room the room for and use 18650’s, and there are plenty of low end laptops and tablets with lipo batteries.
As far as Tesla, I suspect it’s also because it’s easier to automate at high speed and maintain high quality, in addition to cooling. As far as the latter, just look at the Samsung Note fires due to lipo pouch deforment. A corner got crushed a small amount and caused huge problems. The rigid case and tight tolerances of the 18650 form factor makes that problem much less likely.
Almost every single laptop these days uses a lipo because it is more space efficient, they don’t need any special cooling or durability for the battery.
Old laptops used 18650s almost all the time.
You will also never find a modern phone with a cylindrical cell either.
If you’re talking about crappy 26650s then sure, but not a good one like the Shockli 5500mAh cells.
There is no 18650 with that much capacity or current capability.
Not even a 21700.
It actually does, rectangles are 100% space efficient, cylinders are not.
You can fit more capacity per volume using rectangular cells.
More capacity = longer life.
Unlike with car batteries, there is no coolant running between the 18650 cells in a 5 year old laptop.
Standing air does not provide any cooling.
All modern laptops use Lipo packs instead of cylindrical cells for space savings and more capacity.
This is not the reason why macbooks have such long battery life, since there are other laptops with short battery life that also use lipo cells, so in that sense he is wrong.
That does not refute my point. There are low end thin computers, and low end thick laptops. There are also high end thin computers, and high end thick computers. If you want to refute my point properly, show me proof that most high end thick workstation and gaming laptops have switched to lipos.
The cell phone makes no sense. Aside from early car phones, I only know of one cell phone since 2002 that has had a cylindrical battery, and it used a AA.
I’ll oppose my stance. I searched for best gaming laptop, and the most expensive laptop in the first search result was the Razer Blade Pro at $4000. The 5th search result for this laptop shows that it apparently it has a lipo. You can tell because of the swelling.
I’m not a laptop designer, but I think it’s safe to say the lipo needed cooling or protection, or both.
Don’t think it needed cooling, they would have added if needed.
Most if not every laptop (and smartphone and every other consumer device that uses a lipo battery) already has electronic protection.
Pretty sure this is just a problem with the battery itself. Just like the problems with the Samsung batteries.
In that case electronic protection doesn’t do anything, it needs mechanical protection like we see on the cylindrical liion cells. If it would have a venting option the battery wouldn’t swell.
But don’t know if that’s possible with the design of a lipo battery.
Found some interesting reading (at least to me) on the state of the battery industry. I will note that nowhere is battery use in flashlights mentioned in this report. Annual Update on Li ion battery technology 2018