How to Extend the Life of Your Laptop's Battery Charge

In this instructable, you will learn how to extend the life of a laptop's charge. If you are going to be flying or driving long distance, these steps can help make the battery last much longer then usual and make the ride a little less stressful.

There are many simple steps and some more complicated steps but in the end, I was able to achieve an 8 hour charge on my year old laptop. The results will vary for your laptop if you have an inefficient CPU or a high RPM hard drive the gain will be smaller, but generally you will gain more time out of one charge.

In some cases, following these steps can even extend the life of the battery. Which means savings of 100 dollars or more.

The laptop used in this instructable is a HP Pavilion DV5130ca


2.0 GHz - AMD Turion 64
120 Gigabyte 4700 rpm
Broadcom 802.11b/g wireless adapter
128 mb ATI Rage Mobile
Windows XP MCE 2005

All other specifications are insignificant when configuring a PC for power management.

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Step 1: Start Simple

Well for those who don't want to get into installing programs and buying a new battery, these are some simple things you can do to extend the life of a charge.

1. Reduce the brightness of your monitor to the lowest readable level.

The backlight in most laptops are like "mini-fluorescent" (cold cathode) bulbs. They will really drain your battery quickly.

2. Turn off your wifi when you do not need it.

The wifi card is another power hungry device. Think of this - when you make a call on your cell phone, the battery drains very quickly, but if you simply play games or listen to music, it can last a very long time. This is the same idea. The wifi card is "calling" the hotspot all of the time. Even if there isn't a hotspot around, it is continuously looking for one.

3. Use windows primitive power management to control your CPU.

When unplugged from the wall, click on the battery in your task bar and click max battery. This will extend your laptop's life because your CPU will be reduced to a slower speed. (continue reading for a better explanation of reducing your CPU's speed as this makes a HUGE difference in the length of your battery charge.)

4. Unplug unnecessary peripherals.

Unplug that USB light or your wireless mouse when you don't need them. Although minor, these devices could give you those extra few minutes of charge.

Step 2: The Nitty Gritty

The windows power management is fairly primitive when compared to some of the awesome FREE programs out on the net.

The power management application that I use is called "SpeedswitchXP". It gives many more options to you when controlling your CPU's speed.

It gives you the option to set max battery. This setting will reduce your CPU's speed to the minimum that it will go. In my case this is 800 MHz. I know that this sounds ridiculous, but this is actually a very usable speed. I can run Media Center and play my favorite TV shows and forget that I am running at a reduced speed. This is also good for word processing and playing simple games.

This software package also provides dynamic switching. When your computer demands power, it will automatically bump up the CPU's speed to accommodate. If I suddenly decide to play a game of Quake, the CPU will jump to the full 2000 MHz.

I usually don't recommend playing intensive games like Quake because it puts a strain on the battery and discharges them so quickly that it actually damages the cells and reduces the total number of charges that they can ever have.

Google for this program, there are also many others that are similar in nature.


This last step is unnecessary unless your battery will no longer hold a charge for a usable amount of time. Although it does give you a huge gain in the total length of battery life.

Go to a store like Battery Plus and purchase a new laptop battery.

Usually there are two types the high capacity and the standard sized factory battery. I HIGHLY recommend the high capacity battery. This is the main reason why I achieved the 8 hour charge. The high capacity battery's often have more cells than the stock battery's and thus give more charge time.

Step 4: Taking Care of Your New Battery

Be sure to regularly discharge the battery at least once ever two weeks.

It is also important to not put a large strain on the battery.

I do not recommend charging your iPod, surfing the wireless web and burning a movie at the same time. Putting a large strain on the battery discharges them faster then they can safely be discharged. This causes damage to the internal chemistry due to the excess heat.

Most importantly use common sense!

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    40 Discussions


    10 years ago on Introduction

    Okay, those speakser..the Circle ones on the 1st picture. Are the Apple speakers? And are they hooked up to your windows running computer? HOW?! or what are they hooked up to?

    4 replies

    I live in Canada, so we have The Source by Circuit City. These speakers are made by their house brand "Centrios" They are called the color-wave system (or something similar to that...). Unfortunately, they have been discontinued, and I picked these up on clearance. They are regular $149.99 but i got them for 29 bucks! They are not apple, but look like them. They connect using a standard 3.5 mm stereo jack. I now use them with my macbook (I have made the switch and never looked back!) If you do buy these speakers, you will need a subwoofer though. They are lack the low frequency response that name-brand speakers (and larger) speakers can provide. I have them connected to my JBL 200 watt 10 inch sub, which really makes the whole thing sound great. They sound great and the change color when music is played through them. Check ebay, they still may be available!

    thanks for the quick response. Yeah i found the speakers at a garage sale for $1. But I think they only work with an earlier version on Mac. Got a weird little jack that mac put on there (damn you steve jobs). But i hope I can find an adapter. They do not need to be pluged into an outlet, thats why I got them, and they looked sweet! cheers, -beau

    If they do not require an outlet, then they are not-powered speakers. This means that they will require an amplifier unless you want to destroy your audio output by running it at the wrong impedance. I recommend you build a TDA2002 based amplifier. They cost around 7 or 8 dollars per channel and 10 watts is plenty for these small speakers. I would recommend that you disassemble the speakers and use your multi-meter to figure out the pinout and then change the connector to something more standard and build a small inline amplifier. Good Luck!

    oh and i forgot - extending the battery life on the macbook is almost pointless - the power management done through OS X Leopard is simply fantastic. I have tried under-clocking, disabling a core, more frequent hard drive spin downs (i back up often!) and i noticed a very nominal increase (maybe 20 minutes?) at the cost of a less responsive machine. OS X is continuously changing the clock speed of the CPU and using some of the more advanced features of the Core 2 Duo and its chipset to manage power very effectively. All I can say is dim your screen, turn off wifi and bluetooth and you will get optimal battery life. CoolBookController will have little effect on overall battery life.


    10 years ago on Introduction

    i have a hp laptop its about a year old and the battery lasts for about 20 mins lol


    11 years ago on Introduction

    Lithium cells shouldn't be discharged nor charged all the way for the best longevity. To make them last as long as possible, they should be stored at about 80% charge, or around 3.8-3.9V per cell. Two weeks is nothing to a lithium battery. They will hold 98-99% of their charge after two weeks. I'm not sure what discharging every two weeks would accomplish. I would say, be sure to take them out of the laptop when it's plugged in, though, cuz the laptop will keep them topped off at 4.2-4.3V per cell, which will degrade overall longevity.

    8 replies

    Reply 11 years ago on Introduction

    Yeah, true.. stored at 40% and in the fridge/freezer for optimum life. But if you are actually using it, 80% is a pretty good compromise. I misspoke. Even if the battery management is top-dog on your laptop, leaving the battery in it when unused will expose it to the heat of the laptop. So there's no way that leaving it in will improve base longevity.


    Reply 10 years ago on Introduction

    I thought Mythbusters prooved that the battery in the fridge or freezer only makes the battery live for 1-2 min or sothing so small it doesn't realy matter -_-


    Reply 11 years ago on Introduction

    I mean, leaving it in when it's charged and the cord is plugged in, anyways..


    Reply 10 years ago on Introduction

    Is it bad to leave my laptop plugged in almost all the time? I have a Dell inspirion 1525

    I would say that you should probably just pop out the battery when not using it for long periods of time. I usually drain it to anywhere between 50 and 80 percent, then pop it out if I am not going to be using the battery for a couple of weeks. Leaving it fully charged while out of the laptop won't really hurt it either. I have a few laptops that are over 5 years old and their lithium batteries still hold over three hours of charge. Leaving the battery in the laptop will keep the voltage at the highest rated. If you pop it out, then it will allow the battery to "relax"... Macbook's are great, because they allow the battery to drain until around 95 percent, then they pick up again. The laptop isn't using the battery, it is just the natural effect of rechargeable batteries.


    Reply 10 years ago on Introduction

    Call me paranoid, but I believe that some manufacturer's KNOWINGLY OMIT simple battery preservation features on certain models in order to "stimulate the economy." Most of the time, it's easier to just go along with them, though. One warning about partially discharging the battery before removing it: some laptop batteries self-drain at a ridiculous rate due to all the "smart" circuitry. I left a fully charged and perfectly good laptop battery in the fridge for a year, and it ended up damaged.. 2.8V per cell. Some loose cells that had been in there longer than that still measured 4.15V per cell.


    Reply 11 years ago on Introduction

    the help thing on my new hp laptop says that for the best performance you should keep it plugged in as much as possible, and i have the extremely extended battery (about 4 hours) is this a problem or something? laptop - hp dv2500 14inch display - the one without the built in cell network thing


    11 years ago on Introduction

    "Be sure to regularly discharge the battery at least once ever two weeks."

    Unlike the old NiCd batteries, this isn't supposed to be necessary for the newer Li Ion ones. Very different chemistry, no "memory" effect - no reconditioning necessary.

    Excellent advice otherwise.

    1 reply

    Reply 11 years ago on Introduction

    You still should calibrate the charge controller every once in a while by fully discharging and recharging. This lets the controller give you more accurate readings as the battery slowly degrades. It does nothing for the cells, though.


    11 years ago on Introduction

    my laptop battery is worthless,only lasts 2 mins,not enough comon sense to replace the cells which are NiMH since i only sleep for 7hrs