How to choose a power bank for a laptop? Power and capacity criteria.

Charging a laptop on the go, in a cafe, or during prolonged power outages is no longer a problem thanks to portable power banks. However, not every external battery can handle a power-hungry laptop. Standard power banks for smartphones often lack the necessary power and the right connectors. Choosing the right device is a balance between power, capacity, compatibility, and portability. In this article, we will break down the key criteria to consider so your devices always stay connected and operational.

Key Parameter: Power (W) and Power Delivery Technology

The most important characteristic of a power bank for a laptop is its output power, measured in watts (W). Most modern laptops require power adapters with a capacity of 45W to 100W or more for charging. Standard power banks at 5V/2.4A (12W) simply cannot charge such a device; they will only slow down the discharge.

Power Delivery (PD) technology is a mandatory requirement.

To charge a laptop via USB-C, support for the Power Delivery protocol is necessary. This is an intelligent technology that allows the device and the power bank to "negotiate" the required voltage and current. For example, the TALIX 140W power bank supports PD and can deliver up to 100W through a single USB-C port, which is sufficient for fast charging even powerful gaming or professional laptops.

It is also important to check the maximum total power of all ports. Some models, like the TALIX 140W, allow you to simultaneously charge a laptop at 100W and a phone or tablet through additional ports without reducing performance. This makes them true portable power stations.

Capacity (mAh/Wh): How Many Charges Will You Get?

The capacity of a power bank indicates how much energy it can store. It is traditionally measured in milliampere-hours (mAh), but for laptops, it is more useful to focus on watt-hours (Wh). This is a real measure of energy that can be compared to the laptop's battery capacity.

To understand how many times a power bank can charge your laptop, you need to know its battery capacity in Wh (often indicated on the battery itself). The calculation is simple: the nominal capacity of the power bank in Wh is divided by the laptop's battery capacity. For example, a power bank with a capacity of 74Wh (which roughly corresponds to 20000mAh at 3.7V) can fully charge a laptop with a 50Wh battery approximately 1.5 times, accounting for energy losses due to heat and conversion.

It is important to remember the charging efficiency, which is typically 70-80%. Therefore, from 20000mAh, about 14000-16000mAh is actually available for charging. Models with a digital display, like the TALIX 140W, are very convenient as they accurately show the remaining energy in percentages or watt-hours, allowing you to plan your work precisely.

Connectors and Compatibility: Which Ports Do You Need?

Modern laptops are primarily charged via a USB-C port. Therefore, a mandatory requirement for a power bank is at least one output USB-C port with Power Delivery support. However, the ideal option is to have several ports of different types.

Consider a power bank with a combination of ports, for example: USB-C PD (for the laptop), another USB-C or fast USB-A (for a phone/tablet), and a standard USB-A. This will allow you to charge multiple devices simultaneously. Some powerful models are also equipped with a DC connector (round plug), suitable for certain laptops or other electronics.

Pay attention to the input for charging the power bank itself.

To quickly replenish the energy of a large capacity, the power bank itself must support fast input charging. Ideally, you can use the same powerful laptop power adapter via USB-C PD for this purpose. For example, charging a 140W power bank with a compatible adapter will significantly speed up the process compared to standard 18W chargers.

Additional Features and Safety

Beyond the basic parameters, it's worth evaluating additional features that enhance convenience and safety. A digital display is one of the most useful. It can show the remaining charge as a percentage, current output power, or time until full discharge or charge. This is much more informative than four LED indicators.

Protection systems are critically important for expensive equipment. A quality power bank must have built-in protection against overheating, overcharging, short circuits, and overload. This ensures the device is safe for both your laptop and itself. The build quality of the casing is also important; it should be durable and scratch-resistant.

For those who work in the field or travel, weight and dimensions also matter. Powerful power banks with a capacity of 20000mAh and above won't be very light, but modern models are becoming increasingly compact thanks to the use of high-quality lithium-polymer batteries.

Example: TALIX 140W Power Bank 20000mAh

Let's look at the selection criteria using a specific model as an example — the TALIX 140W Power Bank. This device is an excellent example of a powerful portable station. Its maximum total output power is 140W, allowing you to simultaneously charge a laptop, tablet, and phone at maximum speeds.

Its capacity of 20000mAh (74Wh) is sufficient for a full charge of most ultrabooks 1-2 times. The presence of three ports (including a powerful USB-C PD at 100W) ensures versatility. The large digital display accurately informs about the device's status, eliminating guesswork about the remaining charge.

This model also demonstrates the importance of fast input charging: it supports input power up to 100W via USB-C. This means the power bank itself can be fully charged very quickly, which is critical for active users. All necessary protections and a quality casing make it a reliable choice for charging a laptop.