Rebuilding notebook batteries

I would like to try this mod and was wondering if anyone has rebuilt their notebook batteries with success.

My notebook is a F8Sn-C1 and the battery it uses is one that is featured across many ASUS models. I would appreciate any feedback, especially those that have successfully rebuilt an ASUS F8 or A8 series batteries.

For those who are interested in more info, here are some links.

http://www.linuxjournal.com/content/rebuilding-laptop-battery

http://linux-7110.sourceforge.net/howtos/netbook_new/LIbattery/LIbattery.html

Here's a video.

http://www.metacafe.com/watch/479447/laptop_battery_hack_dont_buy_a_new_one/

 

I think it's one of those things, that if you have to ask if this is doable/a good idea, it's propably not for you.

 

http://www.notebookreview.com/default.asp?newsID=4224

What's wrong with spending $100 on a new battery I don't think I will ever be trying this.

 

I've read ppl doing it and if done right can be very effective. If I was doing it, I'd be buying a cheap, h almost new some-other-manufacturer notebook battery off ebay with 18650 cells inside it (voltage will be a multiple of 3.7V, ideally hi-po 2600ma ones), and then do the swap. The 18650 cells can be a pain to source and those sourced (eg: Dealextreme) appear to expire quickly.

 

Not really asking if it's a good idea or doable since I know it can be done and it can be dangerous. What I want to know is if someone here on notebookreview.com has actually performed it with success and can elaborate on the details.

I don't think that is a good example since the battery pack does not appear to have the battery circuit board which controls the voltages, which would explain why the new batteries did not provide adequate power. Plus, that's pretty shoddy looking mod job... I would have at least tried to glue/rubber cement the other half of the housing back on.

The main reason I want to do this is to increase the battery power by rebuilding the battery with new more powerful Lithium-Ion cells.

 

Ahh I don't know enough about this stuff

 

Hell go for it what do you have to lose thats always been my motto and i have been succesful for the most part just research it like crazy first maybe find some video of it then take the proper safety measure get the right tools and have a go at it if you don't try anything new you never learn anything

 

If you can get the cells or tear down another battery AND your comfortable with soldering, go for it, I have rebuilt many battery packs sucessfully ... Killed a couple too

 

Yeah, I'm gonna give it a go on this. I've already put the knife on the battery... but haven't gotten far. The battery housing is trickier to open up than it looks.

Few questions to those that can answer them. The stock battery that came with my notebook is rated at 4800 mAh. Since this is a 6 cell battery, is each battery only 800 mAh? Seems pretty low. Me thinks that I missed something here. Are the batteries supposed to be rated as a pair because of the way they are wired/soldered? So, 1600 mAh each but also rated as 1600 mAh once paired?

I am looking at purchasing six 2600 mAh batteries. The math doesn't quite seem to add up since this would come out to 15600 mAh. I'm guessing I need to divide this number by 2, which would then come out to 7800 mAh. Still not sure if I'm doing the math right. If someone could explain this mAh thing, it would be much appreciated.

Another question is the size of these battery cells. In case the battery cells are not marked, do all notebook battery cells, particularly the ASUS A8/F8 types, come in 18650 size?

 

It's the difference between serial and parallel connections. One ups the voltage, the other the amps (or milliamps as it were).

You're not doing it right even though you may end at the proper result. I don't know the voltage of the thing, but assuming it's around 11 volts (12 nominal perhaps?) they're done in two "pairs of three".

I'm sorry, but are you sure you're willing to attempt this? It's Li-Ion batteries, not NiMH –there's a risk of fire if not done properly.

 

You have 3x2200ma 3.7V cells in series. Two of these sets in parallel.
That way you get 11.1V at 4400ma = 48840maH.

18650 cells are available up to 2900ma, as can be seen in the latest ASUS 1000HE and Samsung NC10 netbooks.

 

keep us updated im curious to see how it turns out

 

If you really intend to do this, buy good batteries that are at least as good as what you have, if not better.

Also - If you make a mistake these batteries can be easily destroyed. If you really mess up they can catch fire or expload. and thus, depending on where your working you might end up burning your house down. The point is that this will be an electrical fire and you won't be able to put it out, plan your space so that you won't need much in the way of supressing the fire.

 

I think I fell asleep during science class when the teacher covered series and parallel circuitry.

Yes, safety first, of course.

I know couple of people who solder for a living so if I get iffy about performing it myself, I can always fall back on their expertise.

I was going to purchase these batteries which already have tabs soldered on them:
http://www.batteryjunction.com/tenergy-18650-tab-2600.html

But the total would come out to $47 for just 6 batteries. Add other tools that I would need to do this properly, the cost will obviously increase further.

I came across this website that sell 5200 mAh ASUS F8 compatible batteries and these supposedly contain high quality panasonic cells (supposedly best in the business?) that are 2600 mAh.
http://www.needbattery.com/Laptop/Asus_F8Sn_BLP2053.html

If I can't find cells that are greater than 2600 mAh, I may just go the route of buying the replacement battery instead.

Not sure how legit the site is though.

 

Actually, that's wrong. The result is not 48840mAh, but 48.84 watts

In other words, it's still 4400mAh, but specified at 11.1 volts.

If it had been at, say, 5000mAh (i.e. 5 amps)@ 20 volts, you'd have a 100 watt battery, and if you had 10000mAh (10 Amps) @ 10 volts, you'd have the same wattage.