Review: Jackery Black420 20,100mAh Power Bank

Jackery Black420 20,100mAh Power Bank











  • Has a Power Capacity that can charge smartphones and tablets to full power
  • Two Ports with Smart Fit and Quick Charge Tech
(Last Updated On: October 30, 2017)

The type of power banks that have high power capacities are ones that are usually the more useful ones. Of course, power banks that have low power capacities are ones that are used more, as they’re smaller and lightweight. However, they can’t be utilized as well as ones that have more power capacity and also more powerful charging capabilities.

This is the reviews for the Jackery Black420 power bank that pack quite a punch with its powering capabilities and a sleek design that few other companies are able to encapsulate with their portable chargers.

RAVPower 20,100mAh Power Bank with Quick Charge 3.0


Power Capacity:

The power capacity is the main attraction when it comes to the Black420 and the reason for that is because it has a 20,100mAh of power to provide. Of course, you won’t be using all of it as there’s some power that’s going to be lost during charging because the energy goes through a conversion from the battery and to your devices.

In this case, we’ll just calculate the average power capacity that you’ll receive when you’re using the power bank; however, it’s important to remember that this charger uses Quick Charge and when it’s used, there’s more power lost during charging because the charging speed is faster. So the average Output power capacity may not be true for those that take advantage of the Quick Charge capabilities.

3.7 x 20,100 = 74,370 / 5 = 14,874

Overall, you’re going to be receiving about 14,500mAh of power capacity and that is still a lot of power that the Jackery Black420 has to offer. Quick Charge will probably bring that to about 12,500mAh because the conversion rate will be less stable, but if you’re using both of the ports with just standard charging, then you’re going to be getting an average conversion rate.

Jackery Black420 20,100mAh Power Bank
(Output Power Capacity = 14,500mAh)
Phone CapacityJackery Black420 20,100mAh Power Bank Left Over Power Capacity

Number of Full Charges for the Device
iPhone SE14,500mAh1,624mAh12,876mAh Left Over

8.9 Full Charges
iPhone 614,500mAh1,810mAh12,690mAh Left Over

8.0 Full Charges
iPhone 6 Plus14,500mAh2,915mAh11,585mAh Left Over

4.9 Full Charges
iPhone 6s14,500mAh1,715mAh12,785mAh Left Over

8.4 Full Charges
iPhone 6s Plus14,500mAh2,750mAh11,750mAh Left Over

5.2 Full Charges
Samsung Galaxy S614,500mAh2,550mAh11,950mAh Left Over

5.6 Full Charges
Samsung Galaxy S6 Edge14,500mAh2,600mAh11,900mAh Left Over

5.5 Full Charges
Samsung Galaxy S714,500mAh3,000mAh11,500mAh Left Over

4.8 Full Charges
Samsung Galaxy S7 Edge14,500mAh3,600mAh10,900mAh Left Over

4.0 Full Charges
Apple iPad Mini 214,500mAh6,470mAh8,030mAh Left Over

2.2 Full Charges
Apple iPad Mini 414,500mAh5,124mAh9,376mAh Left Over

2.8 Full Charges

Power Capacity for Smartphones

The Output power capacity is obviously going to be great to use for smartphones. Although, for a power bank to charge smartphones 5 times or more with just a single charge is something that more power banks have to be built to do because there are lots of newer smartphones that are having higher battery capacities.

In this case, though the Black420 does a great job at providing power to smartphones such as the iPhone 7 being able to charge to its full power 6 times, a Galaxy S8 with its whopping 3,000mAh power capacity is able to charge to full power 3.5 times and a Google Pixel is able to have 5 full charges.

Power Capacity for Tablets

Power banks that have high power capacities are supposed to be able to charge high capacity devices such as tablets. This power bank is able to do just that. The Jackery Black420 is able to charge an iPad Mini 4 or an iPad Mini 2 to full power about two times. It can also charge an iPad Air 2 to its full power about 1.5 times.

Overall, when it comes to its power capacity, the Jackery Black420 has no real issues and can actually last quite a long time when you’re away from a stable source of power.

Output Charging:

The Output charging is just as good as the power capacity.

Smart Fit USB Port:

The standard USB is labeled as “Smart Fit” and that’s basically a way of telling you that it’s meant to for charging standard devices mostly. The Smart Fit port has a charging speed of 5V/2.4A and that means most devices that are Non-compatible with Quick Charge are able to charge at their max speed using this port.

So most smartphones are able to charge at their max charging speeds using this port and the tablets such as iPads that have a max charging speed of 5V/2.4A are best to use with this port.

Quick Charge Port:

The Quick Charge port has the same capabilities as the Smart Fit port and it has Quick Charge capabilities. Most people think that just because a power bank has Quick Charge that it’s mostly meant for those that are own Quick Charge smartphones; that makes sense as those that own Quick Charge compatible smartphones are able to utilize this power bank in a better way because they’ll be able to receive very fast charging speeds.

However, this port is capable of Outputting 5V/2.4A, as well as its 18W of power to Quick Charge compatible devices and even to some laptops such as MacBooks that use USB-C to for charging.

Regardless of what needs charging, if it’s a USB chargeable devices, then this Jackery power bank has got you covered.

Input Charging:

The weak point of power is when it comes to the Jackery Black420’s recharging. The reason for that is because the power bank uses a single Input port that has a recharge speed of 5V/2.0A and even if you’re using a 2 Amp USB wall charger you’re still going to be waiting 10 hours for a full recharge. So it’s best to recharge the power bank while you’re sleeping.

It would make more sense and add more value to the power bank if the Micro-USB Input port used Quick Charge because that way, Quick Change would be useful with Output and Input charging.

Vinsic 28,000mAh Power Bank with 2 Smart USB Ports and Quick Charge

Similar Power Bank


Size and Weight:

Power banks that have high power capacities are meant to be large, as they use more batteries and that results in them being larger and heavier than power banks that have lower power capacities.

In this case, the Jackery Black420 has a length of 6.6 inches, a width of 2.4 inches, and a thickness of 0.8 inches. The weight of the power bank is 13.9 ounces. Truthfully, the power bank isn’t too large and that is a huge relief. Jackery is no joke when it comes to portable charging innovation and that is true when it comes to the power of their power banks and the way that they’re designed.

Sure the Black420 is big and has a good amount of weight to it, but you could take it with you while you’re on-the-go if you found that you can handle it.

Functional Components:

Most of the functional parts of the power bank are just in a single spot and that would be on the short side of the power bank: which is where you’d find two USB ports, the Micro-USB Input port, and the power button.

On top of the power bank, there are 4 White LED power capacity indicators.

You must press the power button to begin charging and the power bank stops charging either when you’re device is full or when there is nothing connected to the power bank.


Structure and Material:

The build quality of this Jackery power bank is simply amazing. The Outer shell is made of Aluminum and then under that, there’s a PC+ABS Reinforcement layer that keeps the power bank safe in the event of a small fall.


On the tech side, the Jackery power bank does basically the same thing that most power banks do, as it provides a safe charging experience.

Thankfully the power bank did not heat up at all during Output charging or Input for recharging of the power bank. The Auto-Shutoff feature is quite welcoming so the power bank doesn’t waste any power capacity.


Regardless if you own a Quick Charge compatible smartphone or not, this power bank is still able to be useful to you. The reason for that is because the two USB ports are still able to offer fast charging speeds even if you’re using two standard charging devices. With that said, if you do happen to own a Quick Charge smartphone, then this power bank simply has a benefit to having it.

The power capacity is going to be very useful for long-term use as it’s able to charge smartphones and tablets to full power a few times.

EasyAcc MegaCharge 16,750mAh USB-C Power Bank

Similar Power Bank



The power capacity of this power bank isn’t the highest on the market, but after its conversion of charging, the Jackery Black420 is able to charge smartphones and tablets multiple times to full power. Quite useful for long-term use without needing a recharge.


It has an absolutely beautiful design, with it having a few parts and all of them have their uses. Even though it does have a high power capacity, the Jackery Black 420 power bank is still quite small and light; if you’re up for it, you can very well take this power bank anywhere with you.


The build quality of this power bank is great, but it’s by no means a Rugged power bank. It has an Aluminum shell and an ABS+PC reinforce casing that’s underneath that enables the power bank to withstand shorts falls.


This power bank is just as reliable for people that don’t own a Quick Charge compatible smartphone, Don’t let the Quick Charge USB Port fool you because both of the ports are able to deliver on equal grounds.

Quick Charge Power Bank Reviews

Specs of the Jackery Black420 20,100mAh Power Bank:

  • Capacity:            Advertised: 20,100mAh            Output Capacity: 14,500mAh
  • Output:

Smart Fit: 5V/2.4A

Quick Charge 3.0 Port

  • Input:    5V/2.0A Via Micro-USB Input
  • LED Power Indicators: 4 White LED Power Capacity Indicators
  • Size: 6.6 x 2.4 x 0.8 inches
  • Weight: 13.9 Ounces


The Jackery Black420 power bank is one of the best standard high capacity power banks on the market currently. It shows with its powering abilities and it’s design features that make the power bank shine through the misinterpretations that high capacity power banks are supposed to be heavy and clunky.

Purchase From:

Harvey Norman


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