Thinkpads Forum

Hi,

I have a T4x / R5x battery here (FRU P/N 08K8193) which is quite dead

Full Charge Capacity: 11.03Wh
Design Capacity 47.52Wh
Cycle Count 481
First Used Date 2005-06

I would like to replace the cells with these cells: http://www.dealextreme.com/details.dx/sku.19770

The refurbishing isn't a problem for me, just some soldering and be sure to keep voltage on the PCB.

But i am interested if the EEPROM inside the battery will learn the new capacity after a while? (from 11.0Wh --> somewhere near 45Wh i think)

I have the button "Improve Battery Health" in the Battery MaxiMiser and i tried that a few years ago with a T4x battery, and it regained some capacity.

I also thought about an OEM / 3rd party battery, but then you don't have the original IBM electronics.
I think an original IBM battery with new cells is more reliable than an OEM / 3rd party battery with OEM / 3rd party electronics.

Would like to hear your opinion.

Nobody ever tried replacing the cells?

Numerous posts about re-celling batteries. I have done several with about 80% success.
http://www.all-battery.com/lgli-ion1865 ... ttery.aspx
http://cgi.ebay.com/1-x-18650-tab-2800m ... 3cb1b06388
This is what you want with tabs. Without tabs you can use. Its a ton of work, and done correctly you are not saving any money. It is a neat hack to do!

Yes it will take 8 to 10 charges for the circuitry to re-learn whats going on.

Ron

frankiepankie wrote:The refurbishing isn't a problem for me, just some soldering and be sure to keep voltage on the PCB.

Are you saying you need to keep voltage on the PCB while soldering the new batteries in? How is this done? I've already taken care of my battery issues for now, but this is good info.

Hi mediasponge,

Excuse me for the late reaction, didn't notice your post

Yes you need to keep the battery PCB powered during the swap, otherwise the controller notices that it was powerless for a small period, and it kills itself I know this because i have tried the recell process before on a T4x battery, and i didn't knew this back then, so when i swapped the cells and put the battery in my T40, the only result i was getting was a fast blinking orange battery LED > battery is dead

I have a lab power supply (0-15V 0-3A) which i can use to keep power (lithium cells are 3,6V nominal voltage) to the PCB.

I sold the T42 that was needing a new battery so i am not going to do this project. Maybe later with another battery but not now.

frankiepankie wrote: I sold the T42 that was needing a new battery so i am not going to do this project. Maybe later with another battery but not now.

Hi Frankie,
I know this isn't exactly an active thread but just wondering if you've gone through with re-celling a ThinkPad battery yet?
It's something I'd like to try and thanks for the info about keeping the PCB fed with power. Unfortunately cells aren't available cheaply locally (that I can find, I'm in New Zealand) and the eBay seller referenced upthread charges 1.5x the cell price for shipping here alone! That makes the cell 2.5x as expensive.

Best,

Yes i have done it.

I replaced the cells and resetted the electronics with BE2Works.

But i can't say that i am happy with the result. Yes, the battery works, but the gauge indication is far off. It works for about an hour and then suddenly jumps from like 36% to 0%, and keeps hanging there for half an hour, and then the laptop shuts off hard (just like *boom* power gone).

I already ran like 15 cycles on the battery, but the gauge isn't adjusting.

It was worth the try, but the result isn't satisfying enough for me. I got the cells from Dealextreme.com by the way.

frankiepankie wrote:Yes i have done it.

I replaced the cells and resetted the electronics with BE2Works.

But i can't say that i am happy with the result. Yes, the battery works, but the gauge indication is far off. It works for about an hour and then suddenly jumps from like 36% to 0%, and keeps hanging there for half an hour, and then the laptop shuts off hard (just like *boom* power gone).

I already ran like 15 cycles on the battery, but the gauge isn't adjusting.

It was worth the try, but the result isn't satisfying enough for me. I got the cells from Dealextreme.com by the way.

Thanks for the info Frankie, really good to know.

I've bought things from DX before with mixed results. Do you care to give any odds on the problem being due to a poor cell/s? If I were to attempt this I'd source more reliable cells.

I have a little X31 that I'm quite partial too and it's (original) battery is down to only holding 34% charge. If I can get my hands on another battery pack for it I'll likely try to re-pack one. As it is, even with only a third capacity, with under-volting the CPU using Notebook Hardware Control I still get over two hours out of the old battery so would hate to lose even that much.

Best,

DX cells aren't the best cells available, i know.

But these ones (i thought it was the blue TrustFire type) came out fairly well. Someone had measured them with an intelligent charger, and they all had at least 2200mAh capacity (advertised capacity was 2500mAh).

And the 'problem' with better quality cells (like Panasonic or something) is the price.. for the price of 6 new cells, you can almost buy a new battery, so in that case i wouldn't go trough the hassle of recelling your battery, but just buy a new one instead.

frankiepankie wrote:DX cells aren't the best cells available, i know.

But these ones (i thought it was the blue TrustFire type) came out fairly well. Someone had measured them with an intelligent charger, and they all had at least 2200mAh capacity (advertised capacity was 2500mAh).

And the 'problem' with better quality cells (like Panasonic or something) is the price.. for the price of 6 new cells, you can almost buy a new battery, so in that case i wouldn't go trough the hassle of recelling your battery, but just buy a new one instead.

Yeah, I agree in principal except it's NZ$245 just for a six-cell battery for my T60 from Lenovo and they're unable to even sell me a battery for the X31. So it's re-pack my own or buy from a company who re-packs them.

You undoubtedly know more about Li-Ion cells than I but isn't it possible for them to test fine one day and be essentially dead the next? Roughly a third of the stuff I get from DX is wasted money (but it generally evens out). Isn't it possible that even one cell 'went wrong' and that could cause what you're seeing? The likelihood of that happening with DX cells is quite high IME, I've bought Li-Ion cell-phone batteries from them and some have been perfect for a month....

Oh, I meant to ask, you mentioned a bench PSU for trickling the PCB. Would two or three Ni-MH cells in series do the same job for the time it takes to re-pack the battery?

Best,

Yes, it could happen that one cell went dead, but i measured the cells after various cycles, and they all measured good (about 3,7V). I can't lay my finger on the exact problem.

No NiMh cells wouldn't work, because the cell in a laptop pack (18650 is the type used) is 3,6 / 3,7V and a NiMh cell 1,2V. I would try if you can keep the old cells connected, then solder the new cells parallel to the old ones, then remove the old cells from their original position, then solder the old cells parallel to the new ones, then desolder the new cells, and then solder them again on their new place.

Sounds complicated but this is the only way to keep the PCB powered if you don't have any spare 18650 cells lying around.


If you need any other info, just ask

frankiepankie wrote:If you need any other info, just ask

Awesome, thanks. I'll bookmark this thread for when / if I get some suitable cells.

Cheers,

I'd sure like to know where you make the cuts on the battery case and how you bond it back together. Battery gauges are nice, but I can live without one if needed.

Anyone hack an Ultrabay battery? They are really expensive for the capacity, but so darn convenient. Gotta admit I sort of gave up and use an ac/dc adaptor with an old car battery.

I made a rough sketch of where to open the battery: http://i.imgur.com/FArUU.jpg

Just pop in a plastic card like an old credit card.

A knife works the best, but is not advisible because it conducts electricity and you could spark your battery.