Anyone who brings up 21700 batteries gets roasted. But why?

There is no difference between an increase and decrease in size.

Percentage wise? Please think again about what you just posted.

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middle school math. always divide smaller number by larger number

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Concerning the percentage calculation: :man_facepalming: Concerning voltage: please tell me the series count. Maybe then youā€™ll understand.

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The difference in number of cells for my 295mm example is just 2 cells 14 vs 16 cells.

Ok Iā€™ve had a good day so far so I am gonna go the extra mile here:

There is a difference between caclulating a volume increase or volume decrease. Basically itā€™s the inverse. A 21700 is 46%(242/165=146%) bigger than a 18650 while a 18650 is 32%(165/242=68%) smaller than a 21700. So there is a difference and context matters.

Next thing is the cell count. Lets limit our calculation on a 12S battery as that is usually the maximum we would use. A 12S1P 18650 battery is 12 * 18mm=216mm in length and 65mm in width. The same in 21700 would be 12 * 21mm=252mm in length and 70mm in width. Or in other words: in the same length of the 12S 18650 battery you would only be able to fit a 10S 21700 battery.

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You canā€™t say that unless youā€™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 stickā€¦ You canā€™t just say length difference between 1 and 2 feet is 100% as it doesnā€™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 canā€™t say something is twice as big as something else?

because making that would actually force you to divide the larger number by the smallerā€¦

Maybe math has changed since I went to school.

Iā€™m gonna leave this thread now to find a wall I can bang my head against.

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Iā€™m sorry if it did, I took my two semesters of calculus a yr. and a half ago, so Iā€™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 couldnā€™t take you seriously after you said this

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To get a percentage yesā€¦ 100Ć·50=2ā€¦ 50Ć·100=.5

ok and what if I want to know what percent 125 is of 100?

would i still divide 100/125? noā€¦

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No then its a proportion.

As 125Ć·100 is 1.25. So 125 is not 125%larger than 100ā€¦

im not saying its 125% larger than 100ā€¦

125 is 125% of 100

you said it yourself 125/100 = 1.25

so now weā€™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 125ā€¦ which is 100Ć·125ā€¦ just depends on what info you want.