When A Battery Is Charged, Or Loses Its Charge, Would Its Weight Change

[sandyRoe]

?

[Old_Geezer]

Doubt it. Way I see it, it has the same number of electrons, they've simply traveled to the other end of the battery.

I suppose some batteries might give off gas.

[Mamyalynne]

Some info here

https://physics.stackexchange.com/questions/34421/does-the-mass-of-a-battery-change-when-charged-discharged

[jim360]

I'm not sure if Mamya's link's answer is entirely correct -- seems overly simplistic. Better to say that there is no change, or, at least, that the change in mass is negligible.

[Peter Pedant]

I think this is O level standard Jim when the answer is no
the charges just shift up and down

I wondered about Lead Acid as I couldnt remember the equations
and found this on wiki
"Overcharging with high charging voltages generates oxygen and hydrogen gas by electrolysis of water, which is lost to the cell."

so yeah in a lead acid system if you overcharge it - not really O levelly

Lithium oxygen - invented after I graduated - interacts with the environment and so the answer appears yes
but that isnt kinda o levelly either

I mean you can use any two dissimilar metals Mg-Cu etc
and nothing much happens

The stack has a bit about a kilogram of electrons
or mole
and I tried that at A level in 1968
and my chemistry master went off his trolley
I didnt make it in science

[wolf63]

Is this you trying to maximise your luggage allowance on your next flight?

[Rev. Green]

Yes, of course the mass changes: energy is mass. If you add energy, you add mass - but not much!