If you want your load to run for 5 hours, put 5 as in our example shown here.
Example, the third field, Temperature Adjustment, is for adjusting the calculations for extreme temperatures. .
Peukert's exponent changes as the battery ages.
Cycle life considerations It isnt good to run a battery all the way down to zero during each charge cycle.Click battery life calculator button to see the estimated battery life result.The amount of charge passing through that wire (conducting.0 amps) in 60 seconds is 60 coulombs, and gate 2013 books for information technology in one hour you would have had said hello and good-bye to 3600 coulombs of charge.When it comes to online calculation, this battery life calculator can assist you to determine the time that how long the battery charge will last.Other DC devices should be rated in amperage.Do you need a 12 volt battery for your application but don't know what size?For our example we are running a 12 volt 15 amp swamp cooler.How much battery capacity do you need to run your device?The Peukert's exponent is determined empirically, by running the battery at different discharge currents.And then sit back and hope for better guidance from marketing!Battery capacity is a measure (typically in Amp-hr) of the charge stored by the battery.
Example, the second field is labeled Load Duration, which is completely up to the user.
Since a battery changes voltage during the discharge, it isnt a perfect measure of how much energy is stored, for this you would need watt-hours.
So it isnt amps, and it isnt amps per hour, it is amp-hours.
So a 100 Ah battery will produce 100 amps for 1 hour.
Eliminating all but one of the features) we got it to run for over.5 seconds before recharging.
Back of the envelope If the current drawn is x amps, the time is T hours then the capacity C in amp-hours is C xT For example, if your pump is drawing 120 mA and you want it to run for 24 hours.12.
The marketing department gave you a specification and all it says is maximize run time, minimize the battery size and cost." But they won't tell you much run time is acceptable, how much size and weight will the market put up with, what cost.If you find a battery with at least this many rated Amp Hours Your Load will run for the desired amount of time at a safe 50 discharge level.Saving your battery life isnt rocket sciencethe general principle is to get rid of the things that are draining the battery the most, and trim down other things that you need to use.Of course a battery makes an awfully weird capacitor because the voltage doesnt drop proportionally to the stored charge, it has a high equivalent resistance, and etc.Math Behind the Magic article.