Laptop Battery help

[AtomSphere]

I have this new battery that seem to not be able to be able to charge. I think it might be my laptop's fault and sadly, my warranty expired.

My theory is that because I over discharged it to some sort of protection point on my laptop or battery(3.54v from each set of 4sets), it then refuses to charge, and if I can charge it a little bit with my DSD charger, the protection problem should reset and be eliminated for now.

This is a second replacement battery an ebay seller (good reputation seller) sent me and it charges fine if i didn't drain it dry (to 3.54v). But if i drain it dry till my lappy shuts off, then it refuses to charge and the windows battery indicator is stuck at 1% with the charging icon.

I pryed open my battery after watching a video on the net that the laptop battery is actually a series of li-ion batteries similar to flashlights. (i didn't know before that)
How can i seperate all these 18650s apart so I can charge them all individually from my DSD charger.
They seem to be connected to the flat metal tab. Is there a way to seperate it from the tab?

 

[MarNav1]

They look like they are spot welded to the ends of the battery and so I don't know if you can separate them. You could always cut the connecting bars in the middle in between the cells with a Dremel or similar
tool but then how do you connect them again? This looks like a real chore
to fix (which I'm sure the batteries designer thought out), I hope you
can fix it.

 

[LEDite]

Atom;

Just charge the entire group with a power supply. 4 sets of cells = 4 x 4.2 =16.8 volts @ full charge.

Then check the voltage for each battery group to see how well they match.

Voltages should be within 0.1 Volt.

If not then charge the low group until they all match.

Reassemble the battery and try it out in the laptop.

Larry Cobb

 

[AtomSphere]

Atom;

Just charge the entire group with a power supply. 4 sets of cells = 4 x 4.2 =16.8 volts @ full charge.

Then check the voltage for each battery group to see how well they match.

Voltages should be within 0.1 Volt.

If not then charge the low group until they all match.

Reassemble the battery and try it out in the laptop.

Larry Cobb

I just charged it all to 3.6v (for each group) and pop it into my laptop. I use wires from my multi-meter and hook it up to my DSD charger and charge each group for a few minutes hope it works cuz windowsxp is still reading it at 1%. Could anyone tell me what voltage protected 18650 cut-off at?

 

[UncleFester]

Hey Ummm.... Please be very careful when charging LiIon cells in series. There is more information available on CPF. Please take the time research it. LiIon cells can be VERY DANGEROUS if not charged properly.

 

[greenLED]

Could anyone tell me what voltage protected 18650 cut-off at?

4.21, IIRC (and it may depend on the charger you're using, etc.), but those are "bare" cells. The attached protection circuit works on the entire pack, not on the individual cells.

 

[AtomSphere]

Looks pretty much like all protected cells to me. Like those we use in flashlights where the + contact point has the black ring

 

[greenLED]

Looks pretty much like all protected cells to me. Like those we use in flashlights where the + contact point has the black ring

:thinking: I don't think so. AFAIK, laptop battery packs are made of bare cells. The large circuit shown in your first pic is the only protection your battery pack has.

I must echo what UncleFester just said - very really careful and make sure you handle these safely. Li-ion explosions are no laughing matter.

 

[koala]

Laptop cells in the battery are unprotected. Charge each of cell to 4.0V and they should be good for some actions but don't expect it to last. Normally, there will be some sort of battery calibration in the laptop BIOS, you might want to try it.

 

[sclemin1]

I recently used http://www.batteryrefill.com/ to refresh a very old laptop battery, the results were great.

 

[AtomSphere]

i spent a long time to charge all batteries to 4.04v and i assemble the whole thing and pop it into my laptop and it reads 1% !!

I think the chip the battery is connected to is screwed as in it hanged or something? Is there any way possible to reset this chip or am i doomed?

 

[koala]

What is your lappy model/brand?

 

[mpk]

Since CPFers are pretty familiar with lithium ion, would it be reasonable do-it-yourself job? The protection board is still in the laptop battery housing, just talking cell replacement here.

The service places charge $75 to $100 to replace the cells. Probably mostly for labor charges.

 

[SilverFox]

Hello Mpk,

I think the cost of quality cells with tabs will run around $50. The rest involves the labor and profit.

If you are comfortable soldering tabbed cells together, have access to tabbed cells, and you can test to make sure the electronics of the pack are good, you should be able to do this. The only remaining issue is making everything fit back in the case.

Tom

 

[Bones]

I think the chip the battery is connected to is screwed as in it hanged or something? Is there any way possible to reset this chip or am i doomed?

Perhaps one of these will help:

http://www.batteryrefill.com/faq.phtml#anchor7

http://www.batteryrefill.com/faq.phtml#anchor8

 

[AtomSphere]

Perhaps one of these will help:

http://www.batteryrefill.com/faq.phtml#anchor7

http://www.batteryrefill.com/faq.phtml#anchor8

Thanks for the suggestion but i already tried it without hope. My laptop seems to be very shitty judging by the problems other people are facing.

Mine is a HP pavilion zd8215us and there are reports of bad DVD drive (software), AC adapter problems, battery problems. Guess its end of the road for this laptop soon...

 

[chris_m]

I think the cost of quality cells with tabs will run around $50. The rest involves the labor and profit.

Though since you can get brand new batteries on ebay for about that sort of money, I'm not convinced it's worth it, unless it's something unusual for which batteries aren't so readily available.

Given I actually buy Dell LiIon batteries on ebay in order to take the cells out to use in my battery packs (I don't have a problem with unprotected cells, since my homebrew drivers incorporate protection circuitry), as that's the cheapest way I've found of buying LiIon cells in relatively small quantities, I'm always slightly baffled by the idea of buying cells to refurbish a laptop pack!

 

[mpk]

Mine is a HP pavilion zd8215us and there are reports of bad DVD drive (software), AC adapter problems, battery problems. Guess its end of the road for this laptop soon...

Have you tried recalibrating? There should be a battery calibration page somewhere. I've used all manner of Compaq/HP for the last several years, and they all have it.

If you've reinstalled the operating system, then you need to download the calibrator from hp.com. It either the "power enhancements" or one of those. I'm pretty sure they only make it for Windoze, though. If you have Solaris, BSD Unix, or Linux you'll have to boot Windoze to do the calibration and switch back later.

 

[mpk]

Given I actually buy Dell LiIon batteries on ebay in order to take the cells out to use in my battery packs

Do fleabay sellers offer reasonably recent li-on batteries? A few magazines say that lithium ion has a shelf life of 3 to 4 years, even if sitting unused.

 

[chris_m]

Yes - I buy brand new packs on ebay, so no worries over life.