External battery power source for laptop

[VK4WDM]

I have a HP Pavilion laptop that I use as my shack computer and for portable digimodes. It works ok using the 230V power pack but is not charging the internal battery. I replaced the battery, but the problem continues.

I took it to a tech who told me that it is not worth repairing, and to junk it, and buy a new one. I am reluctant to do that because it works perfectly OK except for the recharging problem, and is very quiet RF-wise.

Is there anyway I can power it using the the gell-cell batteries I use for my portable transceiver, or by another sort of external battery?

This is probably a "nerdy" question, but computers are not my strong point.

73

Wayne VK4WDM

[VK7DX]

Jaycar have laptop universal chargers that run off 12v(battery,ps etc)
You will need to know the laptop voltage then select off the universal charger.

cheers
Frank

[VK4GHZ]

I have a HP Pavilion laptop that...

Wayne, although I didn't think it was possible, I trust the o/s power management settings haven't stopped the normal charging process?
(With any computer related issue, it's always useful to mention the operating system, up front)

The 12V to 15-24V adapters are relatively expensive!
http://www.jaycar.com.au/productView.asp?ID=MP3472

If you Google "hp pavillion not charging battery" you'll come across many similar stories.
Some have indicated it was a software update that caused the issue, and some claim removing the battery for 5 minutes works as well.
(Bear in mind a lot of the stuff you will find are from consumers with no technical background at all.)

Before spending any hard earned, I'd verify is isn't a software issue etc.

[VK2HRX]

This worked for me.

http://www.ebay.com.au/itm/350648539973 ... 1439.l2649

[VK3DXE]

Keep an eye out for the Aldi Universal Lapto Chargers when they have them. They'll run off 12v and offer a range of outputs and plugs. They're only around $30, so great value for money.

[VK2JDS]

have a look at the voltage on the spec sticker on the battery pack Wayne, dont rely on whats written on the charger as that voltage will not be close to your battery pack volts.
you can tell if its 3 cell or 4 cell. 3 cell will be about 10 volts, 4 cell will be 13 or 14 volts as they use 18650 cells in the packs.

using your old spare battery pack ( you said you replaced the original one with a new one ) crack it open gently by placing in a vice and squeezing it in from the sides applying force from the jaws along the join in the 2 halves of the pack until you hear a plastic cracking noise. this will allow the seal to break between the 2 halves and you can prise open the case

next you will see green coloured 3 volt cells and a circuit board inside. what you want to find is where the positive and negative of the array of cells actually goes into the pcb. this is where you connect up your external leads to go to your externally connected battery. you could try scrapping the pcb too and just link the external battery to the laptop battery socket directly...

i have done this in the past and will have to do it to another laptop of mine here.
running the laptop directly off batteries instead of going through a dc dc converter into the ac adapter socket means it will be a lot quieter on hf. i charged my external laptop battery using a small solar panel as it was remote mounted running constantly as a logger.
keep us posted how you go
73 from Dave vk2jds

[ZL2BKC]

Most laptop batteries are based on Lithium battery technology, and media driven concerns about battery fires, charger fires, etc mean that the manufacturers want to eliminate all possibilities of these occurring (because they are can be very dangerous and life threatening not to mention expensive from a product recall / brand reputation point of view)

To this end the battery packs have an embedded smarts which means when one battery cell charges out of line with the others it will prevent the pack from charging. This state is written into EEPROM in the battery pack controller and it is effectively game over and your battery pack no longer charges.

My Dell laptop had a dead battery so, being capable with the soldering iron, I repacked the battery with 16650 cells from dead batteries I recovered from work. The batteries were good as proven by my iMax B6 balanced charger, but the battery pack would still not charge on the laptop. The laptop charger circuit worked as I had another battery pack which still had life left in it.....
Searching the net I found how to remove the I2C chip and reprogram it to disable the fault bits - I have not gotten around to connecting up my Bus Pirate board to do try this yet.

Also my requirements to run the laptop off a 12V DC supply for portable operation resulted in me purchasing a 100W Universal Power supply (with a 1A USB port which is very handy). It was a cheap china one off Trademe, but it works surprisingly well. I have not checked it for noise on the HF band yet, but my official Dell Charger is not RF quiet there anyway (that is another story!)
With that setup I found the Dell laptop has an intelligent 1-wire digital signal on the charger which tells the laptop of the power supply capabilities and it will not charge the battery unless it detects this signal. Therefore I cannot recharge my battery using the universal charger. This is probably to prevent the charger from working outside of its power ratings, or maybe eliminating 3rd party charges. This is starting to be very common with name brand devices.

73,
Wayne ZL2BKC

[VK4WDM]

Thank you for your replies guys but after another careful check, the problem turned out to be me!

When I was overseas last year the power pack that can with the laptop broke and I got a replacement in Finland. What I did not notice was that there is a very small slotted switch to set the output voltage and it was set on 12V not on 18V Just enough juice to run the innards but not enough to charge the battery.

The only thing that can be said in my defense is that I brought the new power pack before my recent cataract operations

What is even more of a worry is that the tech who investigated the problem did not spot the mistake either

I am still going to purchase an external supply which will be very good for portable ops.

Anybody know where I can get a defrag and memory update on my brain? - the eyes are good now!

73

Wayne VK4WDM