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Battery Watt Hours -Calculator and Kilogram
How much do you know about the battery in your device? For most people, it's just that they need the battery power for their phone or laptop.
However, there is so much to batteries than meets the eye. Among the factors that most end-users may not care about is the battery watt-hours (capacity).
Knowing this is crucial because it can help you buy the right battery and know how best to use it. Not every battery type would be good for you.
In this guide, we introduce you to battery wattage in hours. We hope it helps you understand batteries more.
Battery Watt-Hours Calculator
Let's use batteries in common devices – the lithium-ion battery. This calculator may seem a bit specific, but it's more or less the same for all batteries.
Perhaps you wish to know the battery's watt-hour (Wh) rating to determine shipping instructions but air. This is crucial for all lithium-based cells.
The batteries don't come with a watt-hour rating. But you can find it using the voltage and mAh or Ah capacity.
There are many online calculators that make this process easy. All you have to do is fill in the required figures and let the tools do the magic.
If not, you can get the figures using the formula volts x amp (Ah).
A battery with 11.1v and 4400 mAh. Start by dividing the mAh rating by 1000 to convert it to Ah. This gives you 4.4Ah. Now 4.4Ah x 11.1 Volts gives you 48.8Wh.
Once you know the wattage of the battery, it becomes easier to travel with or use in specific setups. This process is simple and does not take long. You can do this for any battery, and the results will be the same.
Battery Watt-Hours to Amp-hours
A battery's capacity is measured Watt-hours. But you can also find this in Amp-hours for specific setups. Every measurement is useful depending on where it's used.
You can convert amp-hours to watt-hours by multiplying amp hours by volts.
Watt-hours (Wh) = Amp-hours (Ah) x volts (v).
For instance, say you have a 12V battery with a 250 Ah capacity. You multiply 50Ah x 12V to get the battery's watt-hour.
50 Ah x 12v = 600Wh.
It does not get any easier. This battery has a capacity of 600-Watt hours.
Why the conversion?
One of the most important questions we have come across is why convert Amp-hours to Watt-hours? Doing this is important when you want to compare the amount of energy different batteries give.
It all comes down to finding the right power and choosing batteries that can deliver that power. If, for example, you need batteries for a drone or a remote helicopter toy, capacity is very important. You can only know this by converting amp hours to watt-hours.
It's crucial to know the total energy a battery can give. This depends on its amp hours and voltage. Comparing amp hours can therefore help you avoid making mistakes.
Let's say you have battery A and battery B. Batt A is a 36V 12V cell while batt B is 12V 33Ah.
Looking at the amp hours alone, you can assume battery B gives more energy. 33Ah is much higher than 12.8Ah, right?
That means looking at the amp hours alone is like comparing mangoes and apples. But look at the voltages. The batteries are different. It's therefore crucial that it involves voltage for both batteries. We can achieve this by calculating their watt-hours.
This is like comparing mangoes to mangoes to find how much energy you can get from either. In this case, battery A has 36V x 12.8Ah, which comes to 460.8Wh, while battery B has 12V and 33 Ah, which comes to 396Wh.
Battery A, therefore, has more capacity in watt-hours. In other words, it will give you a better performance.
You may be wondering why it happens so. Well, look at electricity as water flowing through a pipe. Voltage becomes the water pressure, while amperage is the rate of flow.
In this case, battery A delivers a higher' flow rate' of electrons, but their 'pressure' is much lower. Battery B is the opposite, with thrice the pressure. Its flow rate is lower, but the extra pressure takes care of that, making Battery B deliver more energy.
Watt-hours to Amp Hours
Now that you know how to convert Ah hours to Wh, let's look at how to convert Wh to Ah. Instead of multiplying, we divide watt-hours by volts:
Ah = Watt hours (Wh) /Volts (V).
Some batteries, like those used in solar generators that you can describe better using this conversation. Consider a Jackery Explorer 1500, for instance. This is a solar generator with a 1534Wh capacity.
To convert this to Ah, you must first find its voltage. The battery comes with 25.5V. You can easily find this information online.
Now, use the equation above to convert this figure:
1534wh / 25.2V = 60.9Ah.
There you have, the Explorer 1500 delivers a capacity of 60.9Ah. You can use this information to determine how much power you might need to run specific applications.
There are many other reasons why anyone would want to convert from Wh to Ah. It's just important for now that it can be done.
Battery Watt Hours Per Kilogram
One kilowatt is equal to 1000-watt hours. This means there are 100 Wh in 1kW, more like there are 1000 meters in 1 kilometer.
Watt-hour per kilogram (W.h/Kg) is a specific energy unit used in measuring energy density in batteries. It is not just in finding capacity for large batteries by identifying how much weight battery energy contains.
1 -Wh/Kg is equal to 3600J/Kg. Understand that this is a unit used in larger batteries, not like the ones in common portable devices.
For example, the batteries in Tesla electric cars give out approx. 254 W.h/kg. Supercapacitors are rated at 3 to 10 W.h/Kg, although research is still ongoing to improve this.
Nuclear batteries can offer to 3300 W.h/Kg. These are some of the most powerful batteries in the world.