Originally Posted by
donrhummy
Trying to understand watt output and storing it in a battery here...
So, let's say I could put out 1000 watts for 5 seconds (as a pro cyclist
), would that fill the battery as much as putting out 200 watts for 25 seconds straight?
Is there some limit as to how much can go across the line to the battery?
Is the percentage of watts actually transferred to the battery static across all watt ranges?
A good approximate model for a battery is a voltage source in series with the internal resistance of the battery. As current flows through the battery, the internal resistance dissipates power and generates heat. The maximum current is limited by how much power the battery can dissipate without exploding or otherwise being damaged.
Power supplied by (or to) the battery is approximately proportional to the current, while dissipation is proportional to the square of the current. Because of this, low currents tend to result in less energy being lost to power dissipation--practicing your sprinting on the trainer is probably not quite as efficient as a slower, steady charge if you do the same amount of work in both cases.