Guide to High Capacity Long Lasting Power Banks

Today’s phones, tablets, laptops, and other electronic gadgets are more powerful hence more power-hungry than ever. And despite having power-efficient processors, you will find yourself needing to charge your devices at times when there isn’t a wall socket nearby. For this purpose, a high capacity power bank is your best friend.

Although high capacity power banks aren’t pocket-friendly, they can fit in your laptop bag, backpack, or glove box with ease. They will provide you enough current to juice up your power-hungry devices several times a day. Also, these long-lasting power banks can be your lifeline when you are traveling to a remote area with no access to electricity.

If you are already looking for one, you have landed at the right place. In this guide, we will help you with your buying decision so that you can opt for the best one without the guesswork. Let’s get started.

Understanding Power Bank Capacity

Before we move to the best high capacity power banks available in the market, you should first understand the secret behind its capacity.

You might have noticed that a 10,000mAh, which should charge your 2,500mAh battery for about four times (from 0 to 100), only charges for 2 to 3 times only. Confused why? This is because mAh is not the right unit to measure battery capacity when the voltages of the power bank and charged devices are different. For example, most power banks use Li-ion batteries that output 3.7 volt (nominal). But the battery in your phone gets charged at 5 volts.

This creates a massive mismatch and might leave you a bit disappointed that you aren’t getting the expected battery life out of your power bank.

Therefore, watt-hours or mWh is the right way to measure your power bank’s batteries’ stored energy as it is voltage-independent. Let’s do simple math for a better understanding of this process.

Consider a power bank of 20,000mAh. It has 20,000mAh capacity at 3.7 volts.

20,000 x 3.7 = 74,000 mWh

Now, after dividing the total mWh of the battery by 5V, you will get 14,800 mAh. This might be the actual capacity of a 20,000mAh power bank.

In addition to the energy lost while converting 3.7 volts to 5 volts, several other factors need to be taken into account, such as ambient temperature, the resistance of the connecting cable, etc.

So, let’s assume there is a 10% loss or 90% efficiency.

14,800 mAh x 0.90 = 13,320 mAh.

13,320 mAh is approximately 2/3 of the on-paper or advertised 20,000 mAh capacity of the power bank.

As the actual charging performance will vary from device to device, you should assume 2/3 capacity of the number advertised on the power bank.

Let’s consider an example of Anker PowerCore 26800 Portable Charger. Suppose its real-world efficiency is 66%.

26,800 x 0.66 = approx. 18,000 mAh.

Hence, it can charge an iPhone 8 (having a capacity of 1,820 mAh) for:

18,000/1820 = about 10 times!

A quick rule of thumb is to assume that your power bank has a real-world capacity of 2/3 of the capacity advertised on the package or site.

Who Should Get A High Capacity Power Bank?

You will need a power bank at some point or another in your life. Sometimes, you might need a backup when you aren’t near a power socket. While a smaller power bank may back you up for an extended workday, you will need something much more long-lasting than a typical 10,000mAh power bank. Preferably the one with a high capacity if you plan on using your phone or tablet on camping trips as well. Therefore, in these cases, a high capacity power bank is your best bet.

However, if you don’t have power-hungry devices and only need a little backup for your smartphone, then these power banks aren’t best for you. Instead, we recommend checking out smaller, more everyday use models, like these best power banks.

Points to Consider Before Buying a Power Bank


You are here because you are in search of a high capacity power bank. As you may already know that a power bank is measured in milliamp-hours (mAh), and your average smartphone has 2,500 to 3,000 mAh battery. The larger the power bank’s capacity, the more juice it will provide to your devices for a longer time.

And if you also want to charge your tablets, notebooks, or laptops, you want one with more than 50,000 mAh of capacity.

Power Delivery

Today’s smartphones use a variety of charging tactics to make the charging process more efficient. From wireless charging to quick charging, there are a lot of things in between. Make sure the power bank you are interested in provides at least 5V/2.0A through its wired ports. If it is providing only 1A, it might be almost useless due to how slow it will charge your device.

If you have a phone that supports wireless charging or quick charge, you should get a high capacity power bank that offers at least one of these two options. Many latest power banks come with an 18W fast charging port; hence you can get one that offers it.


Since a power bank will be your best friend that you will be carrying from one place to another, you want it to be fairly portable. It should fit in your backpack or laptop bag with ease.

The bigger the capacity a power bank offers, the heavier and bulkier it will be. However, a lot of brands have considered this concern, and this manufacturing power banks that are both high capacity and have a sleek design.

Our Top Picks

Where to Buy
Renogy 72,000mAh Laptop Power Bank
Krisdonia AC Outlet Portable Charger 60000mAh 
Crave 50,000 PowerPack Portable Battery Pack Charger
MAXOAK Laptop Power Bank 185Wh/50000mAh
Krisdonia 50000mAh Laptop Power Bank

Renogy 72,000mAh Laptop Power Bank

When talking about high capacity battery chargers or power banks, we cannot ignore this beast of a power bank by Renogy. It has a capacity of whopping 72,000 mAh, and that too in an affordable price! Interestingly, it has a high power conversion rate of up to 90%, which means it is capable of juicing up your devices multiple times simultaneously.

Apart from charging your smartphones, you can also charge your laptop and tablets with ease. It has two USB-A ports, a laptop output port, and a 12V / 15A (Max) cigarette lighter port.

Top Features:

  • Offers a whopping 72000mAh Capacity
  • Reliable Backup Power for CPAP
  • Can charge almost all your electronic gadgets, including power-hungry laptops and tablets (basically the ones under 150W).
  • Backup LED Flashlight
  • Built-in intelligent chips for enhanced safety, including short circuit, overcharge, over-current, over-voltage, and over-heat protection.
  • Comes with 11 adapters for mainstream laptops, laptop power cable, and a user manual

Krisdonia AC Outlet Portable Charger 60000mAh 

Krisdonia has amazed people by manufacturing such a power bank with an AC outlet that provides 110V/130W. Things that you can power up using this beast of a power bank include a wide variety of laptops, phones, TVs, printers, fans, lamps, mini-fridges, and other AC plug devices that are less than 130W.

It weighs 3.9 pounds and has dimensions of 8.66 x 5.94 x 1.57 inches.

Top Features:

  • Constructed with Lithium-ion Polymer battery cells
  • Offers six built-in security protection features
  • The power bank gets fully charged in 8 to 10 hours only.
  • Offers Pass-Through Charging, which means you can power up your devices while it recharges itself.
  • Comes with a 12-month warranty

Crave 50,000 PowerPack Portable Battery Pack Charger

This one is another powerhouse of a power bank offered by Crave. The juice it provides is more than enough to fully charge your mobile devices several times and even charge your laptop for more than once. Moreover, you can also take it inside a plane, unlike the one we mentioned above. It weighs only 4.15 pounds; hence it won’t be a burden on you. It has four ports: 1x PD 3.0 60W Port, 1x PD 18W Port, and 2x Quick Charge (QC 3.0) ports.

Top Features:

  • You can charge three laptops at the same time with this power bank
  • Comes with a PD wall charger
  • Easy to carry in your backpack, suitcase, or bag.

MAXOAK Laptop Power Bank 185Wh/50000mAh

If you have an older laptop and want to charge it on the go, you can rely on this high capacity power bank. It offers two DC outlets (1x 20V DC and 1x 12V DC port) for powering up your DC devices and four USB-A ports. It even comes with various adapters for most popular laptop models.

However, one thing to bear in mind before purchasing it is that it’s too large to take on the airplane. Wondering why? Because it is rated 185Wh, whereas the TSA limit is 160Wh. That being said, it makes an excellent source of power backup when you are in dire need of a power socket to charge your phone or laptop.

Top Features:

  • Conform to UL1642 and UL2056 Standards
  • Constructed with Lithium-ion Polymer Battery Cells
  • Can be recharged in just 6-8 hours
  • It comes with a 12 months hassle-free warranty and a multifunction bag to carry it wherever you go.

Krisdonia 50000mAh Laptop Power Bank

If you are looking for an affordable power bank that offers value for money, you will love this monster. It is a 50,000mAh power bank that can charge your laptops and phones with ease. It weighs only 2.55 pounds and has dimensions of 7.6” x 5.9” x 1.1”. It is rated 185Wh, which means you cannot, unfortunately, take on the plane. Besides that, Krisdonia power bank is an excellent product that can charge your laptop for about 2.5 times and your smartphone for 11-18 times.

Top Features:

  • Conform to UL1642 and UL2056 Standards
  • Constructed with Li-Polymer battery cells
  • Offers four output ports for charging your laptop, phone, and other electronic gadgets.
  • Can be recharged in only 6 to 8 hours
  • It comes with a 12-month hassle-free warranty.
  • You can also adjust the charging voltage and amperage on it according to your requirements.

Some Tips for Maximizing Power Bank Capacity

  • Use Fast Charging or Quick Charge ports only when required. This is because fast charging uses high voltages, like 9 volts or even 12 volts, which reduces the usable battery capacity of the power bank. Therefore, it drains the battery much faster.
  • Use standard 2.0 amp or even 1 amp ports when not in a hurry. This will make your power bank give as much as 20% to 30% more charging capacity.
  • Use high-quality power banks as they have higher efficiency of up to 95% due to well-made, optimized circuits.
  • Use high-quality short cables because they have lower resistance and hence lead to less loss of power.
  • Avoid extreme temperatures as using your power banks in such situations can reduce their efficiency.

Final Words

If you are a power user who cannot travel without technology, then fear not. These high capacity power banks have plenty of juice to keep you going throughout the day or even several days. Whether you are on a road trip or camping in an area where you don’t have access to electricity, a high capacity power bank is your best friend. It can provide you enough juice to recharge your phone many times over or various devices a few times.