Run a Laptop of Some Old Batteries





Introduction: Run a Laptop of Some Old Batteries

This Tech. demonstration is to raise awareness that laptop batteries can easily be replaced with any other kind providing it is of correct, or sufficient, voltage. Here I am using two 6V. batteries rigged up to provide twice the voltage to power a Compaq Armada 110.

*Depending on your laptop warranty this may void it!*

Before reading this Instructable, I recommend reading this one first!!

Step 1: Remove the Power

For this you will need to take your old laptop battery apart, The battery I used was very stubborn and I only got it apart with considerable cosmetic damage, For taking it apart try starting by the contacts where the battery connects to the laptop, I have not got any proper pictures of this step as I did it about 1 month ago, and I only just un-earthed the battery casing, Once you have got a little bit of the battery casing prised up things will either be easier or a bit more difficult, the Compaq battery was fused together so I was practically just breaking plastic!

After you have got the battery apart you will find around 9 battery cells depending on the type of laptop battery. You will need to rip all these chunky batteries out, making sure not to rip the wire leads to the batteries off the circuit board (pic. 2)

Step 2: Source and Improvise the Power

To get some batteries to power the laptop I used the two batteries that are in my 5 million candle power torch, which are rating 6V each so to get 12V they were rigged up together for combined power, I don't know how long they would last fully charged but I estimate at the very least 30mins. 100%CPU

If you are using two batteries you will need to connect the positiver (red) of one battery to the negative (black) of the other battery.

Step 3: Connect the Power.

Now after you have got your batteries the next thing to do is to connect them to the leads of the laptop battery circuit board, you will need to connect positive of your new batteries to the positive lead on the circuit board. I recommend using wires of a decent length for ease, and also using red and black coloured wires attached to the corresponding battery connections (i.e. red to red) it will make things easier.

Step 4: Replace Remastered Battery

I had to cut a little hole for the wires to pass out of the battery casing, remember to thing about this and to do it so that the wires come out in a handy place, don't do this if you don't want to spoil your battery casings good looks.

Step 5: Testing the New Power

It has to be said that I had to use the A/C power connector to boot the laptop but after that it worked fine without the A/C power, I don't know whether this was because the laptop is old or it couldn't recognize the batteries to boot the laptop, but it did recognize the batteries with the A/C power plugged in and the laptop off.



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    The reason you needed the AC power is because you didn't ad another (=) wire to the 3rd terminal on the power connector. This wire sends a 12vdc signal to the motherboard to let it know its on DC power. If you put a jumper in place you will not need the AC power to turn it on anymore.

    Its pretty dangerous. Shorting them out, or deliberately placing them in a fire or anywhere hot.Did it work for you afterward? I expect it did. My hp laptop battery didn't work before and i didn't repire it.I bough a new one from eachbattery. It is a great source for replacement battery if you can find them.

    It is only dangerous if you don't know what you are doing. Laptop batteries can take A LOT before they actually become dangerous.. Shorting them out, or deliberately placing them in a fire or anywhere hot.

    Anyway, good instructable. I learned quite a bit. I am going to use an old 9.6 volt RC battery pack. I disassembled it and removed the 7 or 8 AA 1.2 volt NiMh batteries.. And rebuilding the old pack for my laptop.

    I even have C batteries from an old cordless drill battery pack, still holds a lot of amperage, enough to melt thin wires.


    The best way of opening old laptop batteries and other plastic casings is to heat up a fruit knife or similar with a gas solerding iron and then cutting it up like butter.
    The "Hot knife" supplied with these types of gas soldering irons usually does not work as well. It should be a thin, flat knife. It is actually less painstaking than using a dremel.

    That sounds extremely dangerous, especially since the batteries "can/might" explode if you are not careful enough. But using your method is still better than spending an hour prying that sucker open. XD


    Contrary to "popular misconception" Li-Ion/ Li-Po batteries are not as volatile as, let's say, nitroglycerine or dynamite. Yes, IF they go off you have a fire that is very difficult to extinguish and they COULD explode, but only if exposed to large amounts of heat ( on a larger surface area ) or charged incorrectly, alternately if they were or their original charging device was incorrectly constructed in the factory.

    If you happen to touch them with a thin hot knife, they are NOT going to explode.
    The cells does not contain free gases such as hydrogen, as some old lead batteries would give off when overcharging. Now - THAT could be really dangerous to light a flame around!

    Listen to xeijix!!! the circuit board, besides charging the battery, has a stored key which the computer needs to access before any power is drawn or charging begins. if you remove power from the board for just an instant that key is erased and the circuit board is no good, will never work again. It is much better to use the EXTERNAL power jack, you know the jack where the ac/dc transformer line goes. it is not an ac power jack it is a dc power jack so just supply it with the proper voltage for your particular flavor of laptop and you all set. much better than ripping apart a internal battery. all you need is a plug to fit the jack and your are set- i have used AA batteries before, two packs of six to make twelve to get the required 18.5v for my presario. even made do with a couple of 9.7v packs from my rc planes, boy did those go for ever!

    This is the best and safest way I built a battery pack that when charged it will power the laptop for a week so this works fine for me .

    sorry man,that is false
    i had just disconnected it and reconnected it and it still boots up from the batt

    But in rare cases,that may be your problem.
    That would also be a really badly engineered because some time in a laptops life the battery will drain to the point that its not enough to keep the key in.