Laptop power & battery

Portable power bank won't charge the laptop

Most phone-sized power banks simply don't output enough power for a laptop, so this is often a capability mismatch rather than a fault with either device.

Difficulty
Easy
Time
15 minutes
DIY cost
$30–$80
Pro cost
N/A

Symptoms

  • Power bank shows it's connected but laptop battery doesn't increase
  • Laptop shows a low-power charger warning when connected to the bank
  • Power bank works fine for charging phones but not the laptop
  • Power bank drains quickly trying to charge the laptop

Likely causes

  • CommonPower bank's output wattage is too low for the laptopLaptops typically need 45–100W, while many power banks max out around 18–30W.
  • CommonPower bank doesn't support USB-C Power Delivery at a high enough wattageOnly PD-capable power banks with sufficient wattage can charge most laptops at all.
  • PossibleCable used isn't rated to carry the needed powerA thin or basic USB-C cable may not support high-wattage charging even with a capable power bank.
  • PossibleLaptop's specific USB-C port doesn't accept charging inputNot all ports on a laptop are wired for charging.

What to do

  1. Check the power bank's maximum output wattage and Power Delivery support against your laptop's requirement.
  2. Use a high-quality USB-C cable rated for at least 60–100W if attempting to charge a laptop.
  3. Try each USB-C port on the laptop individually, since some may not support charging input.
  4. Lower the laptop's brightness and close demanding apps to reduce power draw while trying to charge from the bank.
  5. If the power bank isn't rated for laptop charging, use it for phones/tablets and get a dedicated PD power bank rated for laptops instead.

Tools and parts

  • None required
USB-C PD power bank rated 45W or higherSearch: “USB-C PD power bank 45W 65W laptop charging”

When to call a pro

This is generally a capability mismatch to solve by buying the right power bank rather than a repair issue.

Safety

Generally low risk

Generally low risk for a careful person. Stop if anything looks different from what this guide describes.

Related guides

Operator provides AI-generated troubleshooting information. It can be wrong. For safety-critical, electrical, gas, structural, medical, automotive safety, or other high-risk problems, consult a qualified professional.