You can’t say that unless you’re clear about your perspective. A 2 foot stick is 100% longer than a 1 foot stick, but a 1 foot stick is 50% shorter than a 2 foot stick… You can’t just say length difference between 1 and 2 feet is 100% as it doesn’t make sense unless we know the perspective.
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There is no difference between a volume increase and volume decrease. Where is your proof? Percentages are always calculated by dividing by the larger number. Why limit our series to 12 batteries? Our only limit is 295mm of space.
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We are talking about percentage of, I made that clear. A 1 foot stick is 50% of a 2 foot stick.
a 18650 is 68.22% of a 21700
there is no smaller or larger/increase or decrease it is a percentage of the others volume.
so you can’t say something is twice as big as something else?
because making that would actually force you to divide the larger number by the smaller…
Maybe math has changed since I went to school.
I’m gonna leave this thread now to find a wall I can bang my head against.
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I’m sorry if it did, I took my two semesters of calculus a yr. and a half ago, so I’m confident. There is a correct and incorrect way to speak about an objects size in relation to another object. If it is not standardized we can not compare.
Goodnight yall this has been fun
always divide smaller number by larger number
I couldn’t take you seriously after you said this
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To get a percentage yes… 100÷50=2… 50÷100=.5
ok and what if I want to know what percent 125 is of 100?
would i still divide 100/125? no…
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No then its a proportion.
As 125÷100 is 1.25. So 125 is not 125%larger than 100…
im not saying its 125% larger than 100…
125 is 125% of 100
you said it yourself 125/100 = 1.25
so now we’re not diving by the smaller number are we?
Sure sure.its all in how you word it i guess. 125% of 100 or 25 percent larger than 100.
Or 100 is 80% of 125… which is 100÷125… just depends on what info you want.
yea im just a bit annoyed at this thread. Im pretty sure the 30q packs more punch for its size than the 21700 mentioned here but theres no way im doing that math for that just to prove a point.
Ya the tesla 2170 needs to be tested as this will prob beat out the 18650 but we just dont know yet, at least not that i have read.
Wait a second. I think I just might have solved this;
18650/21700 = 86%, so the 18650 is 86% as good as the 21700. 21700 clearly wins!
Or wait, is it 2170? Then the 2170 is (2170/18650) only 11,6% as good as the 18650. 18650 is superior!
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samsung 21700 40t
70.15 mm height 21.10 mm diameter 1.49686 cubic inches volume 4000mAh capacity 3.6v x 4ah = 14.4 kWh 14.4 kWh / 1.49686 cu in = 9.62 kwh per cubic inch 14.4 kWh / 69g = 0.208 kwh per gram
samsung 30q
64.85 mm height 18.33 mm diameter 1.044296 cubic inches volume 3000mAh capacity 3.6v * 3ah = 10.8 kWh 10.8 kWh / 1.044296 cu in = 10.34 kwh per cubic inch 10.8 kWh / 45.6g = 0.236 kwh per gram
Jesus christ i need a life
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Yo7 said you werent gonna do the math…
So, assuming we’re paying per cubic inch (using imrbatteries prices),
buying 40T will cost 13,35 USD per cubic inch, which will give us 9,62 kWh, = 1,39 usd/ci/kWh
buying 30Q will on the other hand cost 5,74 USD per cubic inch, which will give us 10,34 kWh, = 0,56 usd/ci/kWh
Does a possible discharge of 25-30A per cell compared to 15-20A motivate a buy of this cell at 2,5 times the price of a 30Q (volume and capacity equaled out)?
Or does one just like bulkier cells?
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