Are the Battery Capacity Calculations for Electric Vehicles Correct?

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The discussion focuses on the calculations for battery capacity in electric vehicles, emphasizing that battery capacity is defined in ampere-hours (AH), not just amps. The formula for battery capacity is clarified as Battery Capacity = Current * Time, with AH representing the total charge available. The relationship between coulombs and ampere-hours is explained, highlighting that 1 AH equals 1 amp over one hour. The conversation also touches on the definition of the coulomb in relation to amperes and seconds. Overall, the calculations and definitions provided support the understanding of battery capacity in electric vehicles.
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Homework Statement
If an electric vehicle needs to provide 400HP for 1 hour and the vehicles battery voltage is nominally 300V, what is the absolute minimum rating of the battery capacity in Amp-Hours (1HP = 750 W)
Relevant Equations
Capacity = Current * Discharge Time
Battery Capacity = Current * Time
Power = 400 * 750 = 300000 Watts
V*I = 300000
I = 300000/300 = 1000 Amps
Battery Capacity = 1000 * 1 = 1000AH. Are the calculations correct? Why the battery capacity is defined in Amps?
 
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It seems OK.
PhysicsTest said:
Why the battery capacity is defined in Amps?
Not Amps but AH with V given as you got it.
 
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AH (Amp-hours) is a measure of charge. 1AH=1A*3600s=3600 Joules.Coulombs.
 
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PhysicsTest said:
Why the battery capacity is defined in Amps?
The battery capacity is defined in A.h or ampere-hour.
Just like a water tank accumulates volume in gallons (ready to flow out), a battery accumulates charge in coulombs (ready to flow out as well).

Please, see:
https://en.wikipedia.org/wiki/Coulomb

https://en.wikipedia.org/wiki/Ampere-hour

"The SI defines the coulomb in terms of the ampere and second:
1 C = 1 A × 1 s.
The ampere is defined by taking the fixed numerical value of the elementary charge e to be 1.602176634×10−19 coulombs."
 
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haruspex said:
AH (Amp-hours) is a measure of charge. 1AH=1A*3600s=3600 Joules
Coulombs, surely. Or, equivalently, Joules per Volt.
 
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