We use cookies to provide you with a better experience. If you continue to use this site, we'll assume you're happy with this. Alternatively, click here to find out how to manage these cookies

hide cookie message
2,862 Tutorials

How to charge a laptop from a car

Using a cigarette lighter charger

A reader wanted to know how to charge his Acer laptop from a narrowboat. Using his knowledge of charging from a car's cigarette lighter port, our Helproom Expert explained.

QUESTION I'd like to charge up an Acer Aspire 5741 laptop using a 12V (300 amp) battery with no inverter on a small narrowboat. The battery is used to start up the engine and provide power to the internal lighting and water pumps. Is this possible and, if so, how? I don't have a 12V car-style cigarette-lighter socket in the boat at present, but I'm sure one could be fitted. Nick Steinitz

HELPROOM ANSWER No laptop will require anything like 300 amps, Nick. A more realistic maximum is closer to 5 or 6 amps. The problem you're most likely to run into is that laptops typically use power supplies running at more than 12V. The Acer Aspire 5741, for example, uses a 19V PSU rated at 4.74 amps.

If you're willing to fit a cigarette-lighter socket, then a car adaptor is likely to suit your needs. You'll need one with an adjustable output voltage that supports 19V. Maplin sells a 120W adaptor with a selection of interchangeable tips for the laptop end of the cable. We haven't been able to test this, so you would need to ensure that one of the tips fits – perhaps by visiting your local store.

See all How to articles

Get free tech support in the Helproom Forum

IDG UK Sites

How to get a gold Apple Watch for £329: Save £7,500+ with this cool upgrade kit

IDG UK Sites

It's World Backup Day 2015! Don't wait another minute: back up now

IDG UK Sites

Seducing Strangers by Josh Weltman book review

IDG UK Sites

History of Apple: how Apple came to lead the tech industry