Wh is a unit of energy, Ah is a unit of electric charge, basically how many physical electrons passed by.
The voltage of a battery goes down gradually as it is discharged, so getting an accurate value for total energy dissipated is very complicated, as this varies greatly with the discharge profile and other physical factors like the age/health of the battery.
The one thing that stays constant is the amount of electric charge a battery can provide.
If it’s old, the voltage of that charge will be lower and go down quicker, but it will be the same total charge.
I agree from a consumer point of view, joules would be a friendlier unit, however it is also a lot easier to game. Electric charge is a much more definite unit in an electrical engineering sense.
If any of what I said is confusing please ask me to clarify, I’m assuming a basic level of electronic literacy but it’s hard to know what knowledge I’m taking for granted as an ex electrical engineer.
I can’t imagine it’s hard to establish a standard environment for battery capacity testing, or that such a standard doesn’t exist already. Charge might be the more definite unit but it is not the useful unit. I think the closer they get to actually measuring the battery performance the better
Wh is a unit of energy, Ah is a unit of electric charge, basically how many physical electrons passed by.
The voltage of a battery goes down gradually as it is discharged, so getting an accurate value for total energy dissipated is very complicated, as this varies greatly with the discharge profile and other physical factors like the age/health of the battery.
The one thing that stays constant is the amount of electric charge a battery can provide. If it’s old, the voltage of that charge will be lower and go down quicker, but it will be the same total charge.
I agree from a consumer point of view, joules would be a friendlier unit, however it is also a lot easier to game. Electric charge is a much more definite unit in an electrical engineering sense.
If any of what I said is confusing please ask me to clarify, I’m assuming a basic level of electronic literacy but it’s hard to know what knowledge I’m taking for granted as an ex electrical engineer.
As always, a relevant XKCD
I can’t imagine it’s hard to establish a standard environment for battery capacity testing, or that such a standard doesn’t exist already. Charge might be the more definite unit but it is not the useful unit. I think the closer they get to actually measuring the battery performance the better