How to maximize laptop battery life span
For your primary laptop battery
There is no single recommended charging method that works for everyone. Recommended method is determined based on several factors including your preference and your laptop’s design. You can find the charging method suitable for your situation by following the flowchart shown below. Details about the decision point with foot note numbers ([1] to [4]) are explained below the chart. You can also jump to the description by clicking on each decision point.
Figure 1. Battery charging recommendation flow chart
4. Temperature reading: HP Laptop Battery Check
5. Laptop battery usage history
6. Conservative CPU control 
7. Less conservative CPU control
- Battery charge control program from laptop manufacturerSome laptop manufactures ship their laptops with a utility program that allows you to control battery charging process. Using such program, you can control battery charger to stop charging battery well below 100% while keep powering your laptop with AC power. This is very effective to avoid HP hstnn-lb42 laptop battery degradation caused high voltage.Some of the examples are:
- Lenovo Power Manager (Figure 2)You can get to the battery charging mode control screen with the following steps.Control Panel > Lenovo – Power Controls > Switch to Advanced mode > Battery tab > Battery Maintenance…
- Dell Battery Information (Figure 3)You can get to the battery charging mode control screen with the following steps.Start Menu > Dell > Feature Enhancement Pack > Power and Battery > Dell Battery Information > Battery Setting: Change Setting
- Panasonic ECO ModeSee Panasonic ECO Mode web page for the details.
- Measuring laptop computer battery temperatureUse your laptop with AC adapter and fully charged battery. Then run your typical workload for a while and check the battery temperature. Many laptops come with a vendor specific power saving or battery management program and you can read the temperature with it. (Figure 4)If no such program is available for your laptop, you can simply disconnect the HP Pavilion DV6600 Battery(recommended to shut down or hibernate the operating system before that) and feel the temperature of all surfaces of the battery pack.
- Battery capacity you usually use during each battery mode operationUsing Battery Life Maximizer, you can easily see how much battery capacity was remaining at the end of each battery operation. In the example shown in the right (Figure 5), you can see almost all battery operation ended with 20% or more remaining battery capacity.
- Does your laptop slow down without battery?It takes a little bit of work to find out the definitive answer for this question, but generally speaking, this happens when both of the following conditions are met.
- Smaller (such as 65W or smaller) AC adapter is usedYou can find the capacity of your adapter in the label on it.
- Your laptop is relatively new (released in the last couple of years)
The screen shot on the left (Figure 7) shows an example of conservative CPU performance control. This was captured on a laptop with 2nd generation Core i5 CPU with 65W AC adapter. CPU performance is constantly limited to less than 40% of its maximum performance. You can easily feel the performance impact in this case.
Another example (Figure 8) shows less conservative control. This was captured on another laptop 2nd generation Core i3 CPU with 90W AC adapter. In this example, CPU is allowed to run at 100% performance for some time, but occasionally limits the performance to less than 40%. You may or may not feel the performance impact in this case.
For your spare laptop battery
If you have an extra battery that is used only once in a while:
- Charge the battery to half way (40~50%), or if the battery is already charged above half way discharge to half way.
- Disconnect the battery from the laptop and store it in cool (room temperature) place.
- Top off the battery before you use it.
