How to Charge a Laptop with Power Bank: Complete Guide

Running out of laptop battery when you’re nowhere near a plug isn’t just annoying—it can kill your momentum, especially if you’re mid-task, mid-journey, or mid-deadline. Thankfully, today’s USB-C power banks are up to the task—some can even charge your laptop at full speed. You just have to pick the right one. This guide breaks down exactly how to charge a laptop with power bank—what gear works, what to check before you plug in, and how to squeeze the most out of every charge.

alt: Anker power bank charging laptop

Can You Charge a Laptop with a Power Bank?

The short answer to “Can a power bank charge a laptop?” is yes—as long as the power bank supports USB-C Power Delivery (PD) and matches your laptop’s power requirements (volts, amps, and watts).

Modern Windows laptops and MacBooks charge via USB-C ports, and they require anywhere from 30W (20V/1.5A)—for something like a MacBook Air—all the way up to 100W (20V/5A) to power up quickly and efficiently.

The good news is that plenty of power banks now readily support USB-C PD 2.0 or 3.0, delivering up to 100W power to charge most laptops with ease. Some go even further to support the latest PD 3.1 standard, offering up to 140W via a single USB-C port—ideal for high-performance rigs.

Need a real-world example? The Anker Prime 20,000mAh Power Bank packs serious punch in a compact and cabin-friendly size. It offers:

• Up to 200W total outputvia two USB-C and one USB-A port (charge two laptops at up to 100W each simultaneously).
• 100W fast re-charge—full in about 75 minutes via any USB-C port.
• Smart digital displayfor real-time battery% and input/output wattage.
• ActiveShield 2.0 temperature managementfor safe, cool charging.

alt: Anker Prime 20,000mAh Power Bank

{{ component: "product", handle: "a1336-20000mah-power-bank", sku: "A1336011"}}

But what about those old phone power banks you’ve got lying around? Can they do the job? Well, probably not. Most older power banks only support basic USB output—typically 5V/2A (10W) or maybe 9V/2A (18W). That’s fine for phones, but not nearly enough to power up a laptop, which usually needs 15V or 20V to start charging.

And if your laptop still uses one of those barrel-style charging ports, things get even trickier. You’ll need a power bank designed specifically with an AC outlet or a DC barrel output that matches your laptop’s voltage. Alternatively, you might be able to use a USB-C to barrel adapter—but only if the power bank supports 20V output over USB-C PD.

How to Charge Your Laptop with a Power Bank

You see, charging a laptop with a battery pack is straightforward once you’ve got the right setup. Here’s exactly how to charge a laptop using power bank, step by step:

1. Check your laptop’s power requirements

Look at your original laptop charger and note the wattage (V/A). For example, 45W (15V/3A) or 100W (20V/5A). Your power bank needs to match or exceed this figure.

2. Use a proper USB-C PD power bank

Look for a quality laptop power bank that can supply at least the same number of watts via USB-C PD. Many Anker models clearly list these profiles. For instance, the Anker Prime 27,650mAh Power Bank is a sleek soda‑can‑sized powerhouse that delivers ultra‑fast PD 3.1 power and packs all the tech you need to keep your laptop and other gadgets running.

{{ component: "product", handle: " a1340-250w-power-bank", sku: "A1340011"}}

It boasts:

• Up to 250W total outputacross three ports (two USB-C + one USB-A); each USB-C can deliver 20V at 5A (100W), or even 28V at 5A (140W). That’s enough to charge your MacBook Pro 16” (M2) to 50% in just 28 minutes.
• 170W rapid rechargevia dual USB-C ports—top it up to 100% in just about 37 minutes.
• Digital display and Bluetooth appfor real-time stats, locating the bank and smart charging features.
• ActiveShield 2.0 ensures safe temperatures, even under heavy load.
• Large 27,650mAh capacity (≈99.5 Wh), yet safe for air travel.

alt: Anker Prime 27,650mAh Power Bank 250W

3. Get a high-quality cable

To charge laptop using power bank, get a USB-C to USB-C cable with an e-marker chip, rated for at least 100W (5A). The cable is just as important as the power bank.

4. Charge the power bank fully first

Before heading out, ensure your power bank is fully charged. Use a compatible USB-C PD wall charger to refill it efficiently. High-capacity cells deliver peak wattage only when above ~20 % state-of-charge.

5. Connect the cable

When your laptop’s battery is running low, just plug one end of the USB-C cable to your laptop and the other to a compatible USB-C port on the power bank. The two devices will automatically negotiate the highest safe power profile, and your laptop should start charging within a few seconds.

6. Watch for performance issues

If your battery percentage doesn’t move, or your laptop slows down under load, the power bank may not be supplying enough power. Pause intensive tasks or upgrade to a higher-wattage model.

Tips for Maximizing the Effectiveness of Charging Experience

Here are a few smart habits and setup tweaks that can help you charge laptop from power bank more efficiently and extend both their lifespans:

• Keep the Power Bank Above 20% State-Of-Charge: High-watt PD output is only available while the cells have breathing room. Most battery packs pull back once they drop into the last fifth.
• Avoid Charging While Using the Laptop: If possible, charge your laptop while it’s off or asleep. This reduces overall power consumption and allows for a quicker and fuller charge.
• Reduce Live Power Drain:If you’re charging while working, switch to battery-saver mode, dim the screen, close background apps, and unplug any accessories. That way, more of the power goes directly into the battery rather than running your system in real time.
• Charge in the Lithium “Sweet Spot”:For the most efficient energy transfer, start charging when your laptop battery is around 20% and unplug it near 90%. Lithium batteries work best in that range.
• Keep It Cool:High-wattage charging creates heat. Place your laptop and power bank on a hard, flat surface and avoid stacking them to keep temperatures down.

How Many Times Can I Charge My Laptop with a Power Bank?

Wondering how far a power bank will take you? It comes down to battery capacity—both in your laptop and the power bank itself.

To keep it simple, here’s the basic formula:

Number of full charges ≈ (Power bank capacity × efficiency) ÷ Laptop battery size

Power banks usually show their capacity in milliamp-hours (mAh), while laptops list battery size in watt-hours (Wh). To calculate how many charges you’ll get, you need to make sure the units match.

Since some energy is always lost during charging—due to heat, voltage conversion, and other factors—we use an efficiency factor to get a more realistic estimate. Below are some rough calculations for a few popular laptops, assuming 80% charging efficiency and using the Anker laptop power banks mentioned earlier:

As you can see, a 20,000mAh power bank can generally provide one full charge for a 13” laptop, while models like the Anker Prime 27,650mAh give you more breathing room—especially when you’re off-grid or away from an outlet all day.

Conclusion

By now, you’ve got a clear picture of how to charge a laptop with power bank and what makes it work smoothly. It’s not complicated. You just need to use a modern USB-C PD power bank that provides at least as much wattage as your laptop charger—or more, like the Anker models we mentioned above. And don’t forget a compatible 5A cable to handle the power. By choosing the right setup and following a few smart tips, you’ll stay charged and productive wherever the day takes you. Easy.

FAQs

Is it possible to charge a laptop with a power bank?

Yes, you can charge a laptop with a power bank, provided the power bank supports the necessary output for your laptop. Most modern laptops require higher wattage like 45W (15V/3A) or 100W (20V/5A) via USB-C Power Delivery (PD). A power bank with sufficient capacity (usually 20,000mAh or more) and appropriate output (45W-100W or higher) via PD can effectively charge your laptop, making it a convenient solution when you’re on the move or during power outages.

Are there power banks that can charge a laptop?

Yes, there are power banks specifically designed to charge laptops, and they’re becoming increasingly powerful and travel-friendly. Look for models that support USB-C Power Delivery (PD) with high wattage—at least 45W, ideally 100W or more. Anker makes several solid options worth considering. The Anker Prime 20,000mAh (200W, 100W via each USB-C port) is compact yet powerful enough to charge most laptops at full speed, while the Anker Prime 27,650mAh (250W) pushes even more with PD 3.1, delivering up to 140W via a single USB-C for high-performance laptops.

Is a power bank safe for a laptop?

Yes, using a power bank to charge your laptop is generally safe, provided you use a high-quality power bank that matches your laptop’s charging requirements—typically 45W-100W via USB-C PD. Ensure the power bank supports the correct voltage and current for your laptop and includes safety features like overcharge protection, temperature control, and short-circuit prevention.

How does a power bank work for a laptop?

A power bank works for a laptop by storing energy in its internal battery (typically 3.7V cells), then boosting the voltage via a built-in circuit to deliver power through a USB-C PD connection. The laptop draws this power similar to how it would from a wall adapter, depending on compatibility and wattage.