Power banks for charging laptops: How to choose

A power bank can significantly extend your laptop’s battery life, but choosing the right model isn’t simple. Not every external battery designed for smartphones is capable of charging a laptop. Here’s what to pay attention to when selecting a power bank for a laptop.

How to Choose a Power Bank for a Laptop

Charging laptops requires power banks with specific features. These are the key parameters to consider:

Capacity: Look at Watt-Hours, Not Milliamp-Hours

Capacity measured in milliamp-hours (mAh), important for smartphones, is less relevant for laptops due to voltage differences. For example, a 20,000 mAh power bank with a voltage of 3.7 V has a capacity of 74 Wh (20,000 × 3.7 ÷ 1000). For laptops, the optimal capacity is 70–100 Wh — enough for 1–2 charges of an average laptop without significantly increasing weight and size.

Charging Power: At Least 45 W

Unlike smartphones, laptops require higher charging power. The minimum is 45 W, but it’s better to choose models starting at 60 W to ensure stable and fast charging.

Connector Compatibility

Many modern laptops use USB Type-C with Power Delivery (PD) support, which simplifies the choice of a power bank. However, some models, especially older ones, have proprietary round connectors. These require special cables or adapters, which are not always easy to find.