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Humor

eppur_se_muova

(43,052 posts)

5. Most batteries nowadays are sealed systems. Change in weight should be undetectable.

Reply to Wonder Why (Original post)

Fri Jul 10, 2026, 05:28 PM

Friday

The only exception I can think of is the zinc-air battery, which absorbs air as it discharges, and thus gains weight.
https://en.wikipedia.org/wiki/Metal%E2%80%93air_electrochemical_cell

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For you math geniuses out there: If gas weighs 6 pounds per gallon, how much does a [View all] Wonder Why Friday OP

A charged battery does, in fact, weigh more than a discharged battery Gore1FL Friday #1

In a charged battery, the electrolyte consists of concentrated sulphuric acid. mahatmakanejeeves Friday #3

You know, I got a kick out of your question but I daresay that there will be some twitchy fingers on SWBTATTReg Friday #2

Well, thank you for recognizing that this is the humor forum. I was beginning to think I was the only one. Wonder Why Friday #8

A kilowatt is a unit of power. You want a kilowatt-hour, which is a unit of energy. mahatmakanejeeves Friday #4

You do realize this is the humor forum, don't you? The WEIGHT of a KW or a KWH vs the WEIGHT of gasoline? Wonder Why Friday #6

Most batteries nowadays are sealed systems. Change in weight should be undetectable. eppur_se_muova Friday #5

Exactly! It's the HUMOR forum, not the science forum. Wonder Why Friday #7

I did not even notice that. Well, you know more now. eppur_se_muova Friday #9

By the way folks, a full EV 75 KW battery weighs about 3 micrograms more than an empty one. Wonder Why Friday #10

I thought ' a pint's a pound, the world around'. chowmama Friday #11

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