# how to calculate watt hours of a battery

But what is that? Watt specfications for appliances and electronic devices. For each device, multiply the device watt rating by the average number of hours the devices is on for the set time period.

They then calculate the watt-hours for each device and then sum them. There are a number of watt-hour calculators on the web that make it easy to determine total battery watt-hours needed. At that point the battery will be nearly depleated (to 10.6 volts). You may at times need to convert at times between maH and wH (milliamp-hours and W-h), with an ampere being the standard unit if electrical current. The calculator will calculate the battery life if the Watt Hour and the battery voltage is known.

Stansberry has a Bachelor of Science in electrical engineering from San Jose State University. For example, if your PC was rated at 20 watts and was on three hours per day, it would use 60 watt-hours of energy per day. Watt itself is defined as Ampere X Voltage. For information on how this calculator works see How to calculate the Watt Hours (Wh) of a lithium battery. Step 2. A Watt, the measure of power, is usually calculated using this equation: Watts = Volts x Amps. Determine and list the watt rating of each of the device that your battery powers. EV battery size is measured in kWh, or kilowatt hours. Those ratings are only rough estimates. Consequently, multiplying power by a unit of time restores units of energy, and in modern societies, either the watt-hour (W-h) or the kilowatt-hour (kW-hr) is the most often used. For example, say you want to run a 250 watt 110VAC light bulb from an inverter for 5 hours. How to calculate the Watt Hours (Wh) of a lithium battery, Peukert’s Law – how long an amp hour battery will last under a given load, VIDEO – How a zinc-carbon battery is made, VIDEO – How an alkaline based battery is made, VIDEO – How a nickel based battery is made, VIDEO – What makes a deep cycle battery different. In short, watt-hours an amp-hours are …

Estimate the time each of your devices is on over a given time period. His present writing focus is on computer applications programming, graphic design automation, 3D linear perspective and fractal technology. Formula is (Ah)* (V) = (Wh). The key is to use the watts you know to calculate the amps at the battery voltage. Example 1: Must calculate the watt-hour capacity of a car battery having a voltage of 12 volts and capacity of 60Ah: View example: Example 2: Must calculate the ampere-hours of a battery to have 100 watt-hour capacity at 7.2 volts: View example: Example 3: Must calculate the voltage of a battery having 80mAh and 288mWh: View example If we want to calculate how much energy - so, in other words, how many watt-hours - are stored in a battery, you need information about the electric charge in the battery. If your lithium battery does not include a watt hour (Wh) rating on the casing you can calculate it by using the voltage and mAh or Ah capacity.

Note: If the capacity of your battery is expressed in milliampere hours (mAh)—like in the image above— you will need to divide by 1,000 to calculate the ampere-hours (Ah) before multiplying. The calculator will calculate the battery life if the Watt Hour and the battery voltage is known. The battery will last 2 hours. A kilowatt hour is a measure of energy used by an appliance if it were kept running for one hour. Further, if your electronic devices required 10 watt-hours per day and all of these devices needed to be powered for 10 days, the total watt-hours your battery must supply over the 10-day period would be 100 watt-hours--that is, 10 multiplied by 10. BatteryStuff Tech 17 watts / 12.5 volts = 1.36 amps. He has been published in leading technical and business publications such as "Red Herring," "EDN" and "BCC Research." How to Calculate Battery Amp Hours Step 1.Take your time and this will make sense. Of course this is just a simple illustration of how to calculate amp hours. The total number of watt-hours that your battery will need to supply over the set time period is equal to the sum of the watt-hours that each of your devices uses. Watt ratings of appliance and electronic device are often listed on the product.

This rating can be used as the watt rating for the device. This value is commonly expressed in amp hours - amps (units of electric current) multiplied by hours (units of time). Copyright 2020 Leaf Group Ltd. / Leaf Group Media, All Rights Reserved.

running 8 hours is a total of 97.92 amps. And that's because your battery will powers all your electrical appliances and electronic devices. For example, if you have a 2 Ah battery rated at 5 V, the power is 2Ah * 5V = 10Wh. For example, if your PC required 5 watt-hours per day and your fan required 5 watt-hours per day, you would need 10 watt-hours of energy per day. Multiply these two numbers to get the watt-hour rating (Ah × V = Wh). battery image by Aditia Patria Warman from, Alternate-energy: Calculating Watt-Hours, Amp-Hours and Battery Sizing, LibreTexts Physics: Electric Power and Energy, RapidTables.com: Wh to mAh Conversion Calculator. There are a number of watt-hour calculators on the web that make it easy to determine total battery watt-hours needed. This applies to lithium metal batteries (disposable) and lithium ion batteries (rechargeable). For example, if your PC was rated at 20 watts and was on three hours per day, it would use 60 watt-hours of energy per day. Battery Cycle life considerations The battery will last 2 hours. You may need to know the watt hour (Wh) rating of a lithium battery to determine how it should be shipped or to ensure you conform to regulations regarding air travel with lithium batteries. Watt-hours … The actual energy your device consumes is a function of the amount of time it is on and the number of watts is uses. As an example, a 100 Watt light bulb on a 400 Watt Hour battery (like the Yeti 400) would last, on paper, 4 hours. The total energy stored in a battery is also often calculated using watt-hours or kilowatt-hours, for larger applications like car batteries. They use drop-down menus to select the type of appliance, and then they let you specify the average number of hours you use the device per day. Once you know you that number and your battery's watt-hour rating, you will have the information you need to prevent surprise power outages.