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Using external battery VIA existing Laptop battery pack Answered

Hi, I'm one of these people that haven't thoroughly searched these forums for solutions before posting. So - sorry for that in advance!
However I have thoroughly searched in the past, but hadn't found what I was looking for, so that's something :-P .

If anyone would have the good grace to direct me in the right direction i'd appreciate it :) .

I've seen a bunch of 'replace the batteries in your Laptop battery pack' guides, yet i'd like to avoid doing this, and simply use an existing multi-voltage (9, 12, 19v) battery pack I already have - because it's like 16,000mah, and I already take it with me for many other gadgetries already. 

I was thinking I could take apart battery pack, take out dead cells if possible (or leave in if need be), and wire in an input socket to laptop battery pack so I can plug the external batt directly into the internal battery pack.

My WISHFUL thinking is that the charge current going into the battery pack - when normally plugged in and charging would be close enough to what it could get from the external battery pack so I could plug straight into the battery (but could add a voltage regulator from external batt if need be), and the laptop would run as if on battery alone (10.8v 5200mah, 56wh), just for much longer.

So i'd be tricking laptop into thinking it's running from the battery, with the current coming from the external battery pack, as opposed to running at 19v 6.32am, as many external power supplies do.

Laptop: Asus n53sv,
Power brick: 19v, 6.32a

Any ideas?




If you have an external power supply than plug it through the laptops power connector. Trying to hack the existing battery to put in an eternal power connecter is no different than using the existing power connector on the unit. Either way you said your external power source can offer 19V which is what the power connector wants. Hacking it to the batteyr will require a voltage regulator to supply the laptop the power it needs. You'll be loosing power on the regulator so it's more efficient to use the power connecotr.

Hey, thanks for reply. Yeah - that naturally makes sense, yet i'd forgotten to mention that I had tried that, yet the laptop draws a lot more power from the mains than the battery and the external battery couldn't handle it - laptop would just turn off after a few seconds (given it would try to drain from internal battery, which is dead).

It's a pretty beefy laptop with dedicated video card, FHD 15" and 2 hdd's inside, yet when on battery saver mode (when the battery worked), battery was just 'enough' to get by - up to 2 hrs considering on applications. I figured I could get at least 3x2hrs with the 16,000mah external battery.

Yes it draws more power from the plug cause it's trying to run the laptop and charge the battery at the same time. Connecting it through the battery will allow the laptop to run longer but not 3 times longer than the original battery. Not after going through a regulator to bring it down to the 10 or 11 volts needed. Besides you'll need more than a basic regulator to get that voltage. The power going into the laptop needs to be clean and stable.

Right, yeah - here was my thinking:

If I was effectively feeding the external battery power into the battery cells - inside the standard battery - at a compatible voltage for the cells (with a small regulator) then any variances would be managed by the chip in the standard battery and be safe and stable for the laptop?
Are you saying that because of a regulator the battery efficiency would go down significantly? WOuld I be looking at only 2x batt life do you think?

I'm saying the regulator will eat some of the external battery's power in the form of heat. It will be small but still you loose power. You might see 3x more run time and you might not.

Ok, I understand.

Do u think my thinking above makes sense re power going inside existing battery case, as opposed to directly into laptop?

The internal battery is dead right? Than you need to pull the batteries out of the housing and wire the external through the battery housing. Otherwise you could cause the old battieries to blow.

Hey - thanks for your ongoing input.

Yes, exactly. Right, don't leave batteries in.

So giving the same (approx) power to the inside of the internal battery- to be regulated by the magic-wizzyjigs-circuits of the internal battery - should be safe?

Considering the cells in internal battery are dead is there a way to find out what the current that would have been coming out of them, to the inside of the internal battery was (without taking it apart - which may not tell me anyway as they're usually non-branded)?