Wire adapter instead of battery cells laptop

[huub8]

In short, I have a laptop with a broken internal power supply/regulation (it shorts out). So the adapter is still good. It also works when operating on the battery.

What I would like to do is connect the adapter instead of the cells in the battery. Since laptop batteries are more than just a battery I did some quick research and it seems to me that it should work. My plan is to connect three resistors instead of the three cell blocks, to recreate the intermediate voltages. I would connect the 19V adapter to a buck converter, to get the original 11V, and then just connect the plus to the plus and the minus to the minus.

Do you guys think that this would work?

 

[BradtheRad]

Manufacturers ought to make those DC power jacks more robust, and easier to fix. Recently I got a technician's quote of $80 to repair my brother's laptop.

So I had the idea to pry open the battery pack and hook up the power adapter to it...
however I have not gone through with it. I realize I must not allow the batteries to be overcharged.

Your plan is to remove the batteries. However you plan to install a resistor network. You'll need to find out the current draw at those intermediate voltage levels. Your resistors will need to have sufficient power ratings.

Check your adapter's current rating. Your new circuitry will have to handle probably 1/4 or 1/2 of that power level.

 

[huub8]

Thanks for the reply,

The only reason I plan to install the resistor network is to get the right itermediate voltages (since the board inside the battery actually measures them). So I was planning on just using some large/high resistors, that will draw very little current. So that should be no problem right?

I'm also planning on using the original adapter, connected to a buck converter to convert it to from 19V to the needed (about 11) voltage. Since its the original adapter, it should be plenty powerfull right?

 

[BradtheRad]

Yes, the original adapter should work. A buck converter is the efficient way to drop the 19V to 11V.

The technician mentioned something to me about the laptop's battery charging circuitry. It's a question what internal connections it could make or break (possibly extending to the DC power jack), when it senses certain volt levels coming from the battery terminals.

Since you state your laptop works okay from the battery pack, then the charging circuit may not cause a hangup. It is something to be aware of, just in case.

 

[huub8]

I don't think that the charging circuit will pose any problem, since it worked fine using the battery and since the adapter input of the laptop is actually fully removed now, there is no possibility of the laptop trying to charge the battery since there is no other source to get its energy from (so far as I know).