When I first plugged the battery into my laptop it read as completely discharged (even though I KNOW that the cells were shipped partially charged) possibly because the electronics had been unsoldered and lost power completely. I expect they default to a completely uncharged state if they ever loose power completely. An hour later the battery reported that it was almost halfway charged. (My laptop batteries normally take around two and a half hours to charge, getting the first 90% of the charge in two hours, and the remaining 10% a bit more slowly as the charging electronics "top up" the cells.)
At this point I went to bed, so of course I unplugged my laptop because I didn't want a newly constructed battery charging unattended. (I know what I'm doing, but it doesn't hurt to be careful…)
The next morning I plugged the laptop in and after 45 minutes it had reached 99% charged. I believe that this was because it had run up against the "last full capacity: 16880 mWh" setting that was stored by the charging electronics. It stayed at 99% charging for well over an hour, charging at a reported rate of 3109 mW with a voltage that ranged near 12.5 volts ( 12487 mV). Most Li-Ion cells reach full capacity (and regulated chargers usually stop charging) at 4.2 volts (4.2 * 3 is 12.6 volts), so it looks like the charging circuit got the cells very close to a fully charged state, even though they had more capacity than the electronics were expecting.
Once the battery hit 100 % (fully charged) I checked the /proc/acpi/battery/BAT0/info file. It reported that the "last full capacity:" was still 16860 mWh (I was hoping for something closer to 44000 mWh). The interesting thing is that the battery used to report a "design capacity: 44000 mWh", but now it reports "design capacity: 47520 mWh" which is an improvement in the correct direction.
I ran the battery completely down (which took 2 hours and six minutes) by using the laptop normally (but with full screen brightness) for an hour, and then running a script to use 100% of the CPU for the next hour and six minutes. This is about the same battery life I would expect for a brand new 4.4AH battery (I expect 2.5 hours of power when not running the CPU and back-light at 100%) so it looks like the cell transplant was successful.
However, the power monitoring electronics in the battery took a while to get used to the new cells. On the first discharge the ACPI based battery gauge dropped rapidly in the first 45 minutes, and then stuck at 6% remaining for the next hour and ten minutes. However, the laptop BIOS (which controls the color of the power LED) had a better idea about how much life I had left, as the green power led didn't turn orange and start flashing until near the 1 & 1/2 hour mark. Near the end of the discharge period I noticed that the reported "last full capacity" had raised to 20230 mWh.
Over the next several discharge/charge cycles the "last full capacity" slowly raised in approximately 4000mWH increments.
original: 16860 mWH
1st: 20230 mWH
2nd: 24220 mWH
3rd: 29040 mWH
4th: 34750 mWh
5th: 41660 mWh
It appears that the electronics are unwilling to raise their view of the cell's capacity by more than 10% of the design capacity per cycle. The battery has now stabilized with a reported capacity just over 4.1 AH. This is 0.3 AH less than the new capacity of the Li-Ion cells, but it's what I would expect as the charge/discharge electronics are slightly conservative and you can get a few extra minutes of power out of the battery after it reaches "0%".
Knowing what I do now, I could repeat the entire procedure in 2 to 3 hours, so the $7 savings over buying a $50 4.4AH "compatible" battery isn't really justified. However, if you spent $65 for the 2600 mAH cells, you could have a battery that has 8% more capacity than the $100 to $120 official IBM/Lenovo 4.8 AH battery packs (and 15% more capacity, or 22 extra minutes, than my $43 battery) with the same amount of work.
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Jay, thanks so much for the Info! I had never even thought of that!
I bought an old panasonic toughbook for my daughter from ebay, and of course, the battery was dead. cost of a replacment on ebay: about a hundred bucks. a quick google search for the cells found them at about 3.50 each. total cost for 9 cells plus shipping:$45.26
you just saved me at least 50 bucks!
Thanks again! -
Great stuff!
Thanks for mentioning explosive batteries. They really stink too.
Its pretty easy to injure the batteries even if you dont explode them with the soldering iron. (= less capacity)
Warning, from the voice of experience: in addition to taking care to not overheat cells while soldering, also take care to not physically damage or deform the cells such as dent, ding or put undue pressure on them when re-assembling. Any physical damage can lead to an internal short and if the battery has sufficient charge, it will overheat and leak, smoke and/or explode, in that sequence.
BEWARE !!! , not all notebook battery can be refill like this way , some new smart notebook battery got a flash chip inside , when u took off the battery the chip is automatic erase , so you never can recharge your battery , even you change the new cell inside, u only can refill some old nb battery like 5 or 6 year old notebook !
How to know if flash chip is present on battery?
BTW Very nice howto
Plesae could someone tell me where I can purchase these batteries from!?!? The ones that go inside the battery pack.
I bought the batteries (li-ion cells) from http://www.batteryspace.com (it’s listed on the first page of the post.) Others sell them too, if you do a search for “18650 li-ion” on froogle.com plenty of dealers come up.
I got IBM R32 LAPTOP please advise how to open the battery pack and replace with an OEM cells..? Do you have some pics
Much appreciated. Best regards
The R batteries should be very similar to the X batteries. I used a Cell Phone opening tool (Green plastic pry bar) to gradually crack open the battery at the seam and “un-snap” each of the clip in snaps that hold the two halfs together.
I followed your lead and rebuilt my A20m’s battery pack (original IBM # 02K6618). I bought my cells from batteryspace and got the 2600 mAh cells. Worked great! Now, about resetting that flash chip…my pack has an AS358D flash chip. I’ve spent a lot of time looking on the web for info on reflashing the chip, and have only found one thing: “Smart Battery Workshop,” a program that claims it can read and reflash the chip. Problem: another company bought the program’s creators, and now only rebuilds batteries for you. The program was apparently well copy-protected and I can’t find a hacked copy. If anyone can find a way to reset the flash chip, we’ll all be good-to-go.
For those of you not as technicly inclined as most on this forum, and who consider refilling your batteries as a cheaper means of getting your old laptop back in order, this comment is for you. Beware refill services like Batteryrefill.com or the like who promise a “quick turnaround.” If you are the type who needs your laptop for flexibility and needs it often, you are better off buying a new battery rather than wait the 2+ months some of these services take to work on your batter.
Thanks for the great tutorial!
Would you have any advice on how to pry the battery case apart?
Lutz:
I used some plastic tools made for prying cell phones apart. It takes a bit of technique to do it without damaging the plastic. I basically get one of the two tools in place, and then slide it along while using the other tool to keep pressure on the crack.
I used one very much like the following: http://www.apscell.com/prytoolb.html
Jay
I replaced the 6 Li-ion cells in the pack for my IBM T40. I get great prices and service from allbattery.com. I guess I need to reflash the chip in the pack. The batteries measure 3.6 volts, but they won’t charge in the laptop. It sees the battery pack and says it’s 1% charged, but won’t charge.
I thought doing this stuff to my X21 battery. The only problem is: I can’t even start because I’m unable to OPEN the battery case. It’s a tight seal. Did you find this in the X31 battery too?
Eddy:
Yes, the two halves are sealed together very well. I used some plastic “cell phone opening” tools to gradually pry the sides apart, working the crack along as I went.
Jay
>I have a curiosity question
> which I wonder if you have ever considered or heard of
> elsewhere: Substituting lower cost NiMH cells for the Li-
> Ion cells.
While NiMH cells can be used in a battery, you should NEVER replace LiIon cells with NiMH cells. The reason for this is that the charging electronics in the battery are designed for LiIon cells, which are able to receive a much faster charge than the NiMH cells. If you tried to charge NiMH cells with a LiIon charging circuit, they would likely burst, burn, or even explode! Now, if you were able to find a battery pack that was similar to your notebooks (perhaps for an earlier model notebook in the same series that used NiMH batteries, you could replace the (LiIon) charging circuit with the NiMH charging circuit, and then you could use NiNM batteries.
Hi Jay,
which OS and/or which tool do you use to check the capacity?
Greetings from Munich/Germany
Chris
I’m using Linux (with acpi enabled) to get the detailed battery information.
cat /proc/acpi/battery/BAT0/info
Jay
>Hi Jay,
>which OS and/or which tool do you use >to check the capacity?
I found a way to reset the full-charge capacity for Power Manager on WinXP. Follow instructions given by Jay, but perform a “battery gauge reset” between your full discharge/charge cycles.
An additional tip for this to work well is to fully discharge with all timers off, and then fully charge with the thinkpad switched off.
The results are:
- 1st reset: 8.76 to 12.73Wh
- 2nd reset: 12.73 to 13.33Wh (didn’t do something right????)
- 3rd reset: 13.33 to 18.62Wh
- 4th reset: 18.62 to 27.45Wh
- 5th reset: 27.45 to 37.23Wh
- 6th reset: 37.23 to 45.72Wh
- 7th reset: 45.72 to 52.99Wh??
Now my R51e runs for almost 4.5hrs before reaching 1% on “max battery life” settings! (I replaced the cells with 2600mAh!)
Can we do this with lithium polymer?
Robert:
Lithium Polymer cells are basically LiIon cells that are more flexible, so should work just fine for this type of application.
Jay, or anyone, do you know if there is a flash chip set in my Toshiba Satellite M45 S3553? thanks
Also tips for opening up the battery pack would be nice, thanks
hello! and do I can use the NiMH cells and just recharge it in outside recharger not in notebook?
QAD417: I do NOT recommend using NiMH batteries to replace Li-Ion cells. If you did, you could not use the built in laptop Li-Ion charging circuit. You would instead need to use a NiMH charger (either outside the notebook as you suggested, or somehow built into the battery pack). [Of course, if the original battery pack used NiMH cells, you could replace them with NiMH cells.]
My battery at the moment has 4 3.7v (totaling 14.8) cells in series. There is space for 8 cells (there is a large capacity model that uses the same battery case). Could I create 4 banks (in series) of 2 cells (in parallel), still giving 14.8v but doubling the capacity. Will the charging circuit be able to cope? Will the battery me more likely to overheat (I guess the current drawn from each cell will be less so it will be cooler)?
Nathan:
Technically, every cell should be controlled independently. (That is why your existing charging circuit should have a wire that goes to the connections between each cell to the next, so that it can control the charging current to each cell independently.)
However, as long as you stick with a matched set of cells, I expect that you should be 100% safe if you “doubled up” each cell (in parallel). To the charging circuit, it would look like each of it’s individual cells just got more capacity. You are also correct that the power draw from each cell would be halved so the temperature should be cooler. (I expect that your battery would also take twice as long to charge.)
You are indeed lucky to have a battery with extra empty space in it, what model/brand is your laptop?
Jay
Thanks for the quick reply? Now the battery is apart I can see there is only one wire to each pair of cells (actually to the connecter between the two). The laptop is an IPC Multimedia Desknote E (though I have seen it alternatively branded). The battery is an EM-G320L1 (I think made by Elitegroup Computing Systems).
How do you open the plastic case of the Compaq Presario R3000 laptop battery, a 14.8V 6600mAH?
Do I have to cut it open?
Are there any higher capacity cells?
Thanks
I did a restore of my X31 battery and have soldered everything up correctly (looking at your pictures and ones I took before removing old cells) and the battery wont charge.
Watching the temps under linux show they stay normal but the charge/discharge rate doesn’t change. I left it hooked up for 20 minutes and nothing changes…should I just leave it longer?
Adam: It took me about 5-8 charge/discharge cycles to get my new battery charged all the way up (or at least, reporting that it was charged all the way up.)
It could be that the firmware/chip in your original battery does not allow the cells to be “replaced”, but my suggestion is that you run your laptop all the way down every night (and then charge it all the way back up) for a week and see if anything improves.
Jay
Nathan, how did you open the EM-G320L1? There aren’t any screws and I don’t want to tear up the case by prying indiscriminately.
I just opened up my laptop Battery (for Averatec 2300). The computer wont turn on with the battery. I left it plugged to the ac adapter for at least 4 hours, still the battery charge is at 0%.
With the battery case opened up, I can see each battery is at 3.8V, totaling around 11.5V. I even measured voltage at the connector :11.5V. The cells are still good! I guess it’s the flash chip. What can I do?
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