HP and Dell were in a little hot water recently over battery life, after it emerged the two tech giants may have overstated the power of their laptop devices.

Consumer champion Which? tested the average battery life of 67 laptops from some of the industry’s biggest names, to discover whether they matched the claims stated at the point of sale. Not only did all bar one of the seven tested brands fail to match expectations, some only offered around half of the promised power.

HP was found to be the worst offender, managing just 5 hours 2 minutes in tests, despite claiming the battery could keep going for 9 hours 48 minutes. Almost as bad was Dell; its devices providing 5 hours 12 minutes’ running time, even though they should have got nearer 9 hours 15 minutes.

Elsewhere, Asus and Toshiba were found to be around three and a quarter hours short of the mark, whilst Acer and Lenovo gave up roughly two hours ahead of schedule.

The only brand to actually outlast its estimates was Apple, with its devices keeping on for 10 hours 15 minutes, even though the company estimated a 10-hour battery life.

When questioned on the discrepancy, a Dell spokesperson insisted that different uses would put laptop batteries through different stresses – just as driving variations can cause vast discrepancies in miles per gallon. They claimed the ‘real world’ tests that Dell puts its laptops through include Microsoft Office use – which is less of a battery drain than browsing the internet on a WiFi connection (the testing method used by Which?).

How to save your laptop battery life

If you’re looking to eke out every last per cent from your laptop battery, here are three quick tips:

  1. Use eco or battery-saver mode
    This simple switch will limit the battery-intensive operations on your laptop, by switching apps to ‘low-power mode’ and dimming the screen, for example.
  2. Turn off what you’re not using
    It’s all well and good having a laptop with Bluetooth, WiFi and countless other functionalities, but they drain power – perhaps unnecessarily. Switch off any that you’re not using to save battery drain; it’s the same as unloading a heavy car to get the best efficiency.
  3. Don’t multitask
    You may prefer to browse the internet, type up a document and listen to Spotify all at the same time when you’re plugged in, but it’s wise to limit what you do when relying on the battery to only the essential tasks.