Before getting on to conserving battery power, it is worth mentioning that cheap laptop computers have cheap batteries and it is unrealistic to expect a budget computer to last all day on a single charge. When buying a new laptop, pay attention to the battery capacity and expected life.
There may be a choice of batteries or there may be two or three variations of a laptop at different price points. The more expensive models will often have a higher capacity battery that will last longer. It may be worth paying a bit more if you use your laptop away from mains power a lot.
How to store a battery
Do not leave your laptop in a car in hot weather because it can get very hot. Excessive heat degrades the cells of the battery and this reduces the amount of charge that they can hold. This in turn means the laptop does not last as long when running on battery power.
If you will not be using the battery for some time, such as when going on holiday for a week or two, charge the battery up to 100% and then let it run down to 70%. Shut down Windows and make sure the power goes off. Do not simply shut the laptop's lid because it might just go into sleep mode, which will slowly drain the power while you are away.
The best temperature to store batteries is around 20 - 25C ( 68 - 77F), so don’t leave the laptop where it will catch the sun. If you are going away for a winter holiday, don’t leave it where it will freeze.
Any gadgets that are plugged into a laptop will consume power and this reduces the battery life. Unplug external devices like thumb drives and portable disk drives, dongles, such as for a wireless mouse, and so on.
Turn down the screen brightness as far as you can while still being able to see the screen OK. If you sit close to a window you will have to turn the brightness up near the maximum, which drains the battery. Sit well away from the windows and you can turn down the brightness and lower the power consumption.
Turn off Bluetooth if it is on. Click the Action Center icon at the right side of the taskbar and there is a Bluetooth button that acts as an on/off switch. Bluetooth is also in the Settings app in Settings > Network & Internet > Flight mode.
If you can manage without the internet for a while, click the Wi-Fi icon in the taskbar and click Flight mode. Just as with your phone, it turns off all radio - Wi-Fi, Bluetooth and anything else. It uses less power like this.
Use Battery saver
Windows 10 has a special feature to reduce the power usage called Battery saver. Click the battery icon at the right side of the taskbar and click the button to turn it on. This does several things, for example it lowers the screen brightness a little. It also prevents Windows 10 apps from running in the background.
Battery saver is set to turn on by default when the charge falls to 20%, but by then it is too late to save much power. Turn it on manually after starting up the laptop, or set a higher trigger value in Settings > System > Battery. For example, set it to 70 or 80% so it kicks in sooner.
Fix a faulty battery
If you are having problems with the battery, either not charging up or discharging quickly, it is often assumed to be a faulty battery. But it might not be. Try this fix before replacing the battery.
Right click Start and select Device Manager or open it from the Control Panel. Expand the battery entry, right click each Microsoft ACPI... entry and select Uninstall. Close Device Manager and restart Windows.
With some HP laptops, there is a built in battery test. Press and hold the power button for 5 seconds to turn off the laptop. Wait a second and then turn it on. Press the F2 button several times and if your laptop has it, the HP PC Hardware Diagnostics UEFI menu is displayed.
Select Component tests > Power > Battery. There is a quick battery test and a battery calibration that takes anywhere between 2 and 4 hours. Try both.
Advanced power settings
Open the Control Panel and click Power Options, or right click the battery button in the taskbar and select Power Options.
If there is a Show additional plans button, click it to see all the power plans. Select Power saver to enable the laptop to run much longer on the battery. This reduces the computer’s performance and it affects some types of software, such as VirtualBox. Read Speed up VirtualBox enormously with this simple tweak.
On the right of Power saver is Change plan settings. Click the link. Set a short timeout for the screen, such as two minutes. This saves power if you step away from your computer for a few minutes.
Click Change advanced power settings.
Most of the settings are already set for the best power savings, but there are a few that can be tweaked further. For example, if the laptop has a mechanical hard disk, it uses a lot of power. Expand the Hard disk section and expand Turn off hard disk after. This can be set to two minutes, the same as the screen timeout.
Expand Wireless Adapter Settings, then Power Saving Mode. On my laptop it is set to Medium Power Saving, but there is an even better option, Maximum Power Saving. Try it and if there are no network or internet problems, leave it set to maximum.
Scroll down and near the bottom is Processor power management. Expand Maximum processor state. The CPU consumes the most power when it is running flat out, so by setting the maximum speed on battery to 50 or 60%, it limits the power consumed, which enables the battery to last longer.
This obviously reduces the performance of the computer, but few applications require the CPU to run at 100% anyway. You will not notice it when browsing the web, word processing and so on. You would definitely notice it when playing fast action games. However, you should not be playing games on battery power anyway, because it is a killer.
Expand the Multimedia settings and then When playing video. On battery, set it to Optimise power settings.
Check that all the other settings are set to save power too.