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Originally Posted by SailinAway
Can someone please explain the meaning of volts and amps and how they relate to each other? As in, for example, an 80 volt 2 amp battery versus 40 volts 5 amps. Do those terms refer to the power delivered to the arbor or the time capacity of the battery, or both?
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I think you are technically referring to Ah - Amp-hours, not amps.
Without getting super deep into an EE-level discussion, you can think of volts like strength. More volts will generally equate to more power or ability to do something. All other things being equal, an 18v drill will be able to drill a larger hole than a 12V drill.
Amp-hours is a measure of how long the battery can supply that force for (again, simplifying things here). You might prefer to have a battery/drill than can drill 100 1" holes, instead of a drill that can drill a 4" hole, but only 2 of them before the battery dies.
Ah, or Amp-hours, is a rating of how long a battery can maintain its rated voltage or a given amount of power draw. A 5Ah battery can (theoretically) supply 5 Amps for 1 hour, or 1 amp for 5 hours, or 2.5 amps for 2 hours, etc.
In terms of electricity, Watts is the absolute measure of power, and watts is Volts * Amps. A 12V battery with a 5Ah battery can do more total work than a 24V 1Ah battery, but the peak "work" it would be able to do would be lower, limited by the voltage.
Ah ratings can be a little deceptive, as they ignore battery chemistry. Some batteries can be damaged by an excessive discharge, while others can be drawn down to a lower voltage without damage. So in some cases the Ah rating might be what you can actually expect from the battery, and in other cases it represents a number that would damage the battery if you were to actually try to use all that charge/capacity. The Ah rating is also often at an ideal draw, not maximum output. Kind of like MPG ratings on a car, you get optimum mileage within a narrow band of speed, not if you floor it all the time.
For a given manufacturer or brand of battery, higher Ah ratings will equal longer run times or usage between recharges. But across different brands two batteries both rated as 12V / 3Ah might have very different performance curves in real life.