On top of charging mobiles, tablets and other gadgets, did you know that you can use a power bank to charge a laptop?
If your laptop is going to run out of battery and you do not have its charger at hand you can resort to a power bank to continue working or you can also use it as an external battery if the battery of your laptop is broken and you always need to have an outlet nearby.
A power bank can perform the same function as a laptop charger but not just any model will do, it must meet a number of requirements to work as a substitute for the charger:
- Connector: include a cable with a connector compatible with the laptop’s charging port.
- Voltage (V): same working voltage.
- Power (W): same or greater power supplied.
In this Guide we will learn how to identify a laptop power bank taking into account the above requirements and, as always, we will recommend the best models available on Amazon.
Features of a laptop charger
First of all, we need to know the specifications of our laptop charger in order to find a power bank that meets the same requirements.
In the following image we can see the specifications of a laptop charger:
We must check the output parameters (Output):
- Voltage: 19.5V
- Current/Amperage: 4.62A
This means that this charger works at a voltage of 19.5V (volts) and supplies a maximum current of 4.26A (amps).
This charger does not indicate the maximum power that it can supply but we can easily obtain it by multiplying the voltage by the current:
- Power: 19,5V x 4,62A = 90W
Using a power bank as a laptop charger
Next, we need to find a power bank that replaces our charger and meets the following characteristics:
A laptop can be powered through a power bank in 3 different ways, depending on the OUTPUT port it has:
There are 3 types of laptop power banks on the market:
Output port voltage (V) ❗
If we choose to buy a power bank with DC or USB-C PD output it is very important to check that the output port of the power bank has the same voltage* as your laptop charger, otherwise you could irreversibly damage your computer.
This output voltage will always be indicated in the power bank specifications as “DC Output” or “USB-C Output”.
On the other hand, we can also find models that may have one or more DC output ports with a fixed voltage or a single multi-voltage DC port, whose voltage can be selected (by pressing the “Power” button) to the charging voltage of our laptop.
Obviously, if we were to use a power bank with AC output it is not necessary to check the voltage because we would continue to power the laptop with its own charger (which is already in charge of transforming the 220V voltage to the computer charging voltage).
Power supplied (W)
Finally, we must take into account the maximum power that can be supplied by the output port of the power bank:
If the charger of our laptop is 65W then it is advisable to use a power bank that is capable of providing the same or higher power than the charger, because, otherwise, the computer would not even start up as it needs the maximum power during its start-up (and subsequent use) at the same time as it recharges its battery.
However, in the following section we will look at some situations in which it is possible to use a lower power model:
How much power does a power bank need to charge a laptop?
Depending on the laptop model, your charger will be designed to supply a maximum amount of power, i. e: 45, 65, 90 or 130W.
We may not find a power bank that provides the same or a higher amount power than our portable charger either by specifications or budget. In this situation, we can also buy a lower powered power bank.
Let’s say we are working in a coffee shop with our Lenovo Z50-70 laptop (its charger is 65W) and we run out of battery.
We could use a 65W power bank or resort to a lower power one, for example, 45W, to be used under certain conditions:
Best power banks for laptops (December 2021) 🚩
Once you are familiar with the characteristics of a laptop power bank, we present the best models available on the market taking into account the different types of output ports: DC, AC and USB-C PD.
Notice: Remember that if your laptop has a DC charging port and you choose to buy a power bank with USB-C PD port you need to use a USB-C PD to DC adapter.