Use these tricks and tips to ensure your laptop battery doesn't run down when you're out and about and to increase its lifespan.

One of the great advantages of laptops is their mobility. If you're out and about, in a meeting or in a coffee shop, your laptop can connect you to work and friends. But if your battery dies before you can get to a plug, documents and updates can be lost. Batteries don't last forever and we all know they have a mean-spirited trick of running out when you're in the middle of something vital. So here are some power-saving tips that might just allow you the juice to save that all-important document in time.

It's impossible to predict exactly how long a battery will last but here are some of the factors that affect battery life:

• how often you use your wireless network or DVD drive;

• your screen brightness;

• how many programs are running on your laptop;

• if you're using any inbuilt power-saving features;

• the age of your battery.

Work through the list of power-saving tips below to make your battery last as long as possible and remember that you can make adjustments when you're away from a wall socket to get you a little more time.

Power saving tips

Brightness

Use your laptop's brightness controls to reduce the brightness to the lowest comfortable setting. Usually this will be a hotkey combination (Fn + F key). Look for a sun or bulb icon.

Sound

Lower the volume to the quietest comfortable level using a hotkey combination (Fn + F key) or separate volume control. Avoid using the DVD drive when your battery is low.

A CD or DVD drive is one of the most power-hungry devices on your laptop, especially when it's writing discs. Try to use your CD/ DVD drive only when your laptop is running on mains power.

Minimize the use of external devices

External hard drives, CD/ DVD drives and USB sticks all draw power from your laptop's battery. Only plug them in when you need to and disconnect them as soon as you are finished.

Turn off an unused wireless connection

Disable your wireless network card or Bluetooth when not in use. Your laptop will have a hotkey combination or wireless switch for quick access.

Power plans

A power plan is a collection of hardware and system settings that manage how your laptop uses power. These are designed to help you save energy, maximize system performance or strike a balance between the two.

Reduce the number of open programs

Every program running on your laptop uses system resources and therefore draws power from your battery. The fewer programs you have running at the same time, the longer your battery will last.

Extending your battery's lifespan

As batteries get older, they don't seem to have as much energy as they used to - just like the best of us! Even though you've given it a good night's charge, the battery still needs a mid-afternoon nap and any strenuous activities wear it out in no time. While its lack of power may leave you feeling a little flat, there's no need to retire your battery just yet. There are a number of simple ways to extend your battery's lifespan and while they won't return it to the heady days of its youth, they'll at least put a spring back in its step.

Things that can drain your laptop's battery life

1. Batteries wear out a little each time they go through a charge cycle, whether the battery is charged from flat or nearly full. If the battery is used regularly for short periods and then recharged, it will wear out faster. Many users leave their laptop on a desk running on mains power. Doing this, removing the battery and only using it when you go mobile will increase its lifespan.

2. Laptops run on lithium-ion (sometimes called Li-ion) batteries, which gradually lose their performance over time. The decline is very gradual and you may not notice any difference for a long period but when they get near the end of their lives, their performance will very suddenly drop off and your battery will only last for 10 minutes or so. A very short battery life is a sign that it is time to purchase new batteries.

3. Even if you don't use your laptop, the Li-ion battery will slowly discharge over time and will eventually need recharging again. If the battery is left in your laptop, it will discharge quicker as your computer uses a small amount of power from your battery even when it's shut down.

Caring for your battery

Your computer's user guide or manual will have recommendations for battery usage and storage. In addition, you can take the following steps to prevent a short battery life or low capacity:

1. Store Li-Ion batteries between 20°C and 25°C with approximately 50% charge.

2. Do not expose the battery to high temperatures for extended periods. For example, don't leave your laptop/battery in a hot car or next to a radiator.

3. Remove the battery when the computer is going to be stored or not used for more than two weeks.

4. Remove the battery from the computer if it's going to be plugged into mains power continuously for more than two weeks.

If your battery is not charging

If your battery runs completely flat, it may appear that it isn't recharging. Don't be alarmed, as your battery is designed to allow only a 'trickle charge' when charging in this state. It does this to prolong the battery's life and prevent overheating.

Once the battery has charged to a certain level, it will start charging at a normal rate again. You may need to leave your battery charging for up to 12 hours.

Calibrating a battery

Sometimes the computer and battery can get out of sync and your laptop can misread the remaining amount of charge. For example, Windows may display that you have an almost full charge, only to drop down suddenly to almost nothing in a short space of time.

Use one of the following methods to calibrate the battery and you will get a more accurate guide to the life of your battery.

Calibrate the battery while your laptop is in use with Windows 7

A calibration cycle requires that the battery be completely charged and then completely discharged. Here is a step-by-step guide to doing so:

1. Connect the mains adaptor and fully charge the battery.

2. Unplug your mains adaptor.

3. Open the Start menu, type 'power' in the Search Programs and Files panel and press Enter.

4. Choose Power Options from the Control Panel section.

5. Click Create a Power Plan from the left hand menu and click Next.

6. In the On battery column, select 'Never' for the following options:

-Dim the display

-Turn off the display

-Put the computer to sleep

7. Press Create and close the Power Options.

8. Allow the battery to discharge completely until the PC shuts down; this may take some time.

9. Connect your mains adaptor and restart the computer.

10. Return to the Power Options and select your desired power plan.

The battery is now calibrated.

Calibrate your battery when not using your computer

For this you need to completely charge and then discharge your computer's battery. Calibrating your computer this way can take several hours, depending on the age of the battery and your computer's configuration.

Follow the steps below to calibrate the battery power meter readings:

1. Shut down your computer.

2. Connect the mains power adaptor and charge the laptop until the battery is completely charged. (Note: your computer's User Guide will have details on how your battery indicator light shows this.)

3. Restart the computer and start tapping F8 while it boots up.

4. Ensure Safe Mode is highlighted in the Windows Advanced Boot Options menu and press Enter.

5. Unplug your mains power adaptor from your computer.

6. Allow the battery to discharge completely until your computer shuts down.

7. The battery is now calibrated.