Most people (not all) don't know this but you should: How do you determine the number of times or how long a power bank can fully charge your device ? Find out

How do you determine the number of times or how long a power bank can fully charge your device ?

So a couple of days ago, I was literally on the hunt for a laptop powerbank for my system due to the poor power supply that has invaded my locality. One thing was clear to me, I needed something that could charge my laptop for at least 8 hours. I wasnt settling for less. If there was no power supply, I wanted something I could easily rely on on full charge.

After what I would refer to as a stressful hunt, I eventually found one at a computer store some kilometers away from my locality, they called this commercial area where this store was found "The computer village because basically various computers, laptops and technological hardwares are being sold in this very location.

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Yeah I eventually found a laptop powerbank in a large scale store in computer village, mind you, this was almost like looking for a needle in an haystack. I found a laptop powerbank alright, but the question was, this so called laptop powerbank bank I found has a capacity, can the capacity of this power bank charge my laptop for 8 hours?

I began questioning the sellers because the last thing I want was investing my money in something that wont serve me efficiently in the long run. I needed a guarantee, which obviously they were very careful about giving. After so much questioning which must have felt like an interrogation, they opted for putting through on how to determine theoretically if the powerbank electrical capacity was capable of giving me what I was looking for.

After being educated, I was eventually able to calculate how long a powerbank with a specific capacity can charge my laptop based on some specific details. Here is how to do such calculation and spare yourself the guessing game and having to relying so much on the information of the seller

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Alright, imagine the power bank is like a big bucket of water and your device is like a small cup. The size of the bucket (power bank) determines how much water (power) it can hold. The size of the cup (device) determines how much water (power) it needs to fill up. You might want to read that again if it unclear

Now, pay attention, when you look at a power bank, you will see a number followed by "mAh" (milliampere-hour). This number tells you how much power the power bank can store. The higher the number, the more power it can hold.

To figure out how long a power bank can charge your device, you need to know how much power your device needs. You can usually find this information in the device's manual or online. Sometimes this information can also be found on the device battery label especially if its a device that uses a battery like laptop or a smart phone.

Once you know the power bank's capacity (in mAh) and your device's power requirement (also in mAh), you can divide the power bank's capacity by the device's power requirement. This will give you an idea of how many times the power bank can charge your device fully.

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For example, if the power bank has a capacity of 10,000mAh and your device needs 2,000mAh to charge fully, you can divide 10,000 by 2,000 to get 5. This means the power bank can charge your device fully about 5 times before it runs out of power.

Another example to make this clearer, let's say you have a power bank with a capacity of 20,000mAh and a smartphone that requires 3,000mAh to charge fully. To find out how many times the power bank can charge your smartphone, you would divide the power bank's capacity by the smartphone's power requirement:

20,000mAh (power bank capacity) / 3,000mAh (smartphone power requirement) = 6.67

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This means that the power bank can charge your smartphone fully about 6.67 times. Since you can't have a fraction of a charge, this would round down to 6 full charges.

So, in this practical example, you could charge your smartphone about 6 times with the 20,000mAh power bank before it needs to be recharged. This gives you a good estimate of how long the power bank can keep your device powered up on the go.

Remember to keep in mind that factors like the efficiency of the power bank, the charging speed of your device, and yes any additional power consumption during use can affect the actual number of charges you get. But using the capacity of the power bank and the power requirement of your device is a good starting point for determining how long the power bank can charge your device in real life situations.

What you also have to keep in mind that, the actual charging time may vary depending on factors like the efficiency of the power bank and the charging speed of your device. But by doing this simple math, you can get a rough estimate of how long a power bank can charge your device which can save you a lot of hassle and probably being scammed by sellers

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Okay have you have done your theoretical calculation on how long a powerbank or the number of times a powerbank can fully charge your device, there are some factors that can make this theoretical calculation not so or in some cases far from accurate in practicality. Here:

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1. Efficiency Loss: When you charge a device with a power bank, some of the power gets lost in the form of heat or through the charging process itself. This means that not all the power stored in the power bank goes directly into your device, so you may get slightly fewer charges than the theoretical calculation suggests.

2. Device Usage While Charging: If you use your device while it's charging, it will consume power at the same time as it is being charged. This can reduce the number of full charges you get from the power bank because some of the power is being used immediately rather than going towards charging the device.

3. Battery Degradation: Over time, the capacity of the power bank and the battery of your device may decrease due to wear and tear. This means that the power bank may not be able to hold as much power as it did when it was new, and your device's battery may not be able to hold a full charge like it used to.

4. Charging Speed: Some devices charge faster or slower depending on the type of charger used. If your device supports fast charging, it may consume power more quickly from the power bank, reducing the number of full charges you can get.

5. Inconsistent Power Drain: The power consumption of your device may vary based on how you use it. For example, playing games or watching videos will drain the battery faster compared to simple tasks like reading or texting. This means that the power bank may not provide the same number of charges in all situations.

These practical reasons show that the theoretical calculation of how long a power bank can charge a device may not always match up exactly with what happens in reality due to various factors that can affect the charging process.

I hope with this you can easily make a rough estimate as to how long / the number of times a powerbank cam charge your device. Remember theory doesn't always equals practical, but atleast you are not going in blind.

Thanks for reading, hope this was helpful ?

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Resources consulted

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• https://powerbank20.com/en/actual-output-capacity/
• https://www.quora.com/How-do-I-calculate-the-number-of-device-charges-a-power-bank-can-provide
• https://www.xtorm.eu/blogs/news/how-often-can-i-charge-my-phone-with-a-power-bank
• https://imazing-power.com/pages/how-long-does-it-take-to-charge-a-phone-using-a-power-bank
• https://mobisun.com/en/blog/what-does-mah-mean-for-a-power-bank/
• https://canyon.eu/blog/how-long-does-a-power-bank-last/
• https://blog.nitecorestore.com/power-banks-how-long-to-charge.htm

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Credit

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^{All images used are mine}