Lemmy Shitpost @lemmy.world zurohki @aussie.zone 4d ago

Battery tech really does move fast

Just two years ago my car's 50 kWh battery weighed around 350 kg, now you can get a 45 kWh battery that fits in the palm of your hand!

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"Vegita, what does the lab equipment say about that battery bank's power level?"

"It's over nine million!"
Judging by those USB plugs that hand is enormous
- I’m tired about all these jokes about my giant hand! The first such incident occurred in 1956…
- At first, I was concerned about that much energy in such a small package.
  
  Now I'm afraid of that giant hand.
I see they also invented a new connector standard, Nano-USB Type C.
- ? Are you talking about the lightning connector?
Its also 9000000000000000000 MAH at 0.0000000000001V
- This is why mAh shouldn’t be used to measure battery capacity
  
  Its actually useful because a battery has a specific operating voltage. It should be required to put both.
I love how we still needlessly use so many zeroes instead of just calling it Ah. Phones with 5000 mAh batteries. Or you know, we could just cal it 5Ah battery. Chinese are even further obsessed with this just adding zeroes because the more zeroes the better!
- Even better: we could use Wh instead, to not constantly correct for voltage!
  
  But then you can't inflate the numbers by putting a 3.7 volt battery in a power bank, listing the capacity in amp-hours and implying that you get that many amp-hours at the power bank's 5V output voltage.
  
  But you get more zeros with Ah 😂
- Yeah but Americans are stupid and thought a 1/3lb burger was smaller than a 1/4lb burger. I fully expect they'd think 5Ah is smaller than 1000mAh.
- I've wondered in the past why, for example, 1000 kilometers are still referred to as kilometers.
  
  The moon is roughly 385 megameters away, or 0.4 gigameters!
  
  Do we use MM for megameters and mm for millimeters? i think this might start to get confusing. We should probably clarify a few things before some tradie apprentice builds the galaxy's largest bookshelf.
  
  Hehe, nice catch. Technically, under SI standard we could call that 1 megameters... It's mostly we rarely address distances beyond 1000 kilometers in day to day life so kilometers still make some sense. Where under Imperial units, there isn't any unit above mile. For batteries, we don't really use anything less in phones anymore, only smartwatches and earbuds use capacities under 1000.
  
  People don't use megameters enough that you can rely on them knowing what it is nor have an intuition for it even if they technically know.
- I’ve even seen people say “5k mAh”
I think 45 kWh is more than I use in a month, so I'd love to take this baby to a restaurant or something, "forget" it, bring it back home and profit
- I'm ootl. "Forget it"?
  
  Like just leave it there for a day or so in an unassuming nook to charge up
You'll want to duck for cover if the battery gets punctured on this one.
- Its only comparable to tens of KGs of TNT, stop worrying about it.
- I don't think you'll have the chance to wait for a puncture before it spontaneously explodes
Hey Vegeta, what does the battery say about its Ah level?

IT’S!!!… nine thousand.
The picture talks only about stored charges, not energy, maybe it gives only a couple nano volt.
The power of the sun, in the palm of my hand!
Could this power my home for 8 to 10 years?
- It's designed to fail the day after the warranty expires.
- It's impossible to say, but if we assume it's a typical Li-ion battery supplying 3.7V, then:
  
  9 kAh x 3.7 V = 33.3 kWh
  
  So, it would be enough to power the average American house (10 MWh/year) for 1.2 days, or 4 days for a typical European flat (3 MWh/year).
  
  Edited wrong yearly consumption
  
  I think your math is off given that just a typical US consumer full sized refrigerator can use ~650 kWh/year and still be considered Energy Star qualified.
  
  What, my house used 78 kWh yesterday.
  
  You are off by a factor 1000 on the household power consumption (I think these numbers are without heating or assumes that you don't have electrical heating?). And the voltage could be anything on a magical battery ;)
Why does that device have rocket engines?
- That's the heat exhaust. 9 million mAh can get really hot
Five year warranty is nice.
Someone buy this so they can tell me how big it is, and how long before it dies for good. Please.
- Smaller than a credit card, didn't last opening the package

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