Thinkpads Forum

Hello, my first time posting here ^^

I just bought the sexiest x61t on fb marketplace. The only issue is that the battery only lasts for one hour. It uses an aftermarket 4-cell battery afaik. I'm trying to find a replacement battery online but all of the ones I found are on old, somewhat sketchy sites for 100$+ (I'm in Canada) Does anyone know what my best option for procuring a new battery would be?

I saw that there are 20$-40$ x61 batteries on aliexpress, maybe it could be possible to cut the plastic on those a little bit to get it to fit the x61t? Or does someone maybe know where I could get reasonably priced aftermarket x61t batteries?

Thanks for reading

Can you take a picture of your X61 Tablet battery? I need to see what exactly your battery uses, if a replacement is impossible to buy.
If yours is an original 4 cell battery, then chances are it uses 4 Sanyo UF103450's. They are nearly impossible to find in North America, but I will be getting a batch of Panasonic NCA103450's directly from China.
If yours is an aftermarket 4 cell battery and if it has a hump, then chances are it's using 18650 cells.

I also have a X61T (tablet) that I recently acquired as a "For parts only" unit. Repaired it, but the battery pack appeared to be dead (battery LED on laptop is flashing quickly). I found this replacement on Amazon: https://www.amazon.com/dp/B09PL9TZTX?re ... asin_title

Haven't received it yet so can't comment on its quality.

I am still attempting to repair the original battery pack, but even after charging the individual cells up to 3.7 volts, I still get the fast blink from the battery LED.

babblefish wrote: ↑

Sun May 11, 2025 10:03 pm

I also have a X61T (tablet) that I recently acquired as a "For parts only" unit. Repaired it, but the battery pack appeared to be dead (battery LED on laptop is flashing quickly). I found this replacement on Amazon: https://www.amazon.com/dp/B09PL9TZTX?re ... asin_title

Haven't received it yet so can't comment on its quality.

I am still attempting to repair the original battery pack, but even after charging the individual cells up to 3.7 volts, I still get the fast blink from the battery LED.

What FRU is your original battery and what maker is it?
If it's dark burgundy red, it's Sanyo. If it's brighter red, it's Panasonic.
Sanyo packs would most likely have a BQ8030 that's easy to deal with with the right tools, Panasonic has the M37512 which is much more of a pain, but still possible. Not sure what BMS chip LG has
You'll need a USB to SMBus bridge adaptor, like the CP2112 that I offer, or the Cypress FX2LP, EV2300/2400. You can also make do with an arduino, but codebase for that is still very incomplete at the moment.

The FRU is: 93P5032. The cells are a dark burgundy red. And it does have a BQ8030 chip on the board. And I do have Arduino boards, but I can get a CP2112 pretty easily.

To reset the board, I was hoping disconnecting the battery leads from the board for a minute then reconnecting would do it. Any thoughts about this?

babblefish wrote: ↑

Wed May 14, 2025 12:05 am

The FRU is: 93P5032. The cells are a dark burgundy red. And it does have a BQ8030 chip on the board. And I do have Arduino boards, but I can get a CP2112 pretty easily.

So indeed, Sanyo with BQ8030, which is a Sanyo firmware chip (TI merely made the chip hardware, shipped to Sanyo completely blank). This chip is by far the most common on old ThinkPads and is also the most discussed about chip in how to get into it, so all is easy with a CP2112.
CP2112 is easily obtained on the likes of Aliexpress, or if you are interested in supporting my work and eliminate the hassle of trying the wiring, I sell pre-made idiot-proof 7 pin ThinkPad connector to CP2112 converters along with the CP2112 on this forum: viewtopic.php?f=11&t=137243
As to how to use it for BQ8030, there is the easiest way using a cracked copy of BE2Works 4.52 with one-click repair, there is a more involved way using open source DJI Battery Killer, which requires some manual operations to get it set up for BQ8030. There are also SMBUsb repos on github, but I learnt the hard way that the CP2112 version of SMBusb is buggy and can brick your firmware (program flash)!
That BE2Works 4.52 crack is a bit shady and you have to use it in your own risk, on an XP machine. I can provide a copy upon request (PM).

babblefish wrote: ↑

Wed May 14, 2025 12:05 am

To reset the board, I was hoping disconnecting the battery leads from the board for a minute then reconnecting would do it. Any thoughts about this?

Umm... This is unfortunately a very naive myth that for some reason keeps on circulating on YouTube. It's one of those things where so many people want to believe it's true that they make it like it's truth, but in reality, it only applies to an early BMS like the ones found on a 600 or a 770 indeed can be "reset" in this way, and also if all the BMS encountered was temporary problems, this could fix it.
But in your case, the battery LED is flashing orange, meaning the lock flag is already written into the EEPROM, no amount of hardware tinkering can fix it short of you outright blowing up the BQ8030.
And, there is also a misunderstanding of the terms here by most people. For the BQ8030, the term "reset" really is just restarting the firmware on the chip, normally doesn't do much. There is entering boot mode, the equivalent of download mode on an android smartphone, which lets you read and write the ROMs. The term of "reset" or "unlock" by most people is actually the removal of Permanent Failure flags (PF flags) inside the EEPROM. THIS is what you eventually want to end up achieving, and on the BQ8030/8050/8055, you do it by enterring boot mode with a set of SMBus commands, and then read EEPROM, change the EEPROM, and write it back. Only after this, as well as restoring the fuse, will your battery start working again.

Hey all! I also got an X61 tablet just recently with a dead battery and wondering what my options are for replacing or repairing it. I'm very new to the ThinkPad world, so much of this conversation above has gone over my head, but I'm very open to learning. Are there any particular go-to sites to find replacement batteries/parts for the classic ThinkPads?

johnny1093 wrote: ↑

Sun Oct 26, 2025 9:02 am

Hey all! I also got an X61 tablet just recently with a dead battery and wondering what my options are for replacing or repairing it. I'm very new to the ThinkPad world, so much of this conversation above has gone over my head, but I'm very open to learning. Are there any particular go-to sites to find replacement batteries/parts for the classic ThinkPads?

As kfzhu was on about earlier, aftermarket options for these laptops have dried up a few years ago. You may see some replacement packs for sale here and there, but they might have sat for that long. And some of them don't have good fitment, not a good option for a daily-use machine. I used to have on myself.

I'm capable of rebuilding these batteries, and have done so already on a 4-cell. Sourcing the prismatic cells needed to swap out the originals isn't straightforward either. But it works great!

Medessec wrote: ↑

Sun Oct 26, 2025 7:00 pm

johnny1093 wrote: ↑

Sun Oct 26, 2025 9:02 am

Hey all! I also got an X61 tablet just recently with a dead battery and wondering what my options are for replacing or repairing it. I'm very new to the ThinkPad world, so much of this conversation above has gone over my head, but I'm very open to learning. Are there any particular go-to sites to find replacement batteries/parts for the classic ThinkPads?

As kfzhu was on about earlier, aftermarket options for these laptops have dried up a few years ago. You may see some replacement packs for sale here and there, but they might have sat for that long. And some of them don't have good fitment, not a good option for a daily-use machine. I used to have on myself.

I'm capable of rebuilding these batteries, and have done so already on a 4-cell. Sourcing the prismatic cells needed to swap out the originals isn't straightforward either. But it works great!

Re "rebuilding these batteries" is this something that you or anyone else here provides as a service? Or could you point me to a tutorial for this? If this is all too much of a hassle I might just look into buying another x61 that already has a functional battery...either way thanks for the info!

johnny1093 wrote: ↑

Tue Oct 28, 2025 7:55 pm

Re "rebuilding these batteries" is this something that you or anyone else here provides as a service? Or could you point me to a tutorial for this? If this is all too much of a hassle I might just look into buying another x61 that already has a functional battery...either way thanks for the info!

I'd imagine for X61 batteries right now, it'd just be me. I'm not sure of anyone else (besides kfzhu) who can do it, and kfzhu isn't trying to take on too many jobs like that right now. There are a few tutorials on resetting batteries like these, but it's not reliable at all, and it sounds like what you'd want is a full rebuild anyways (all new cells). Swapping in new cells isn't straightforward, you definitely need knowledge/experience with wiring, electronics, and the dangers of Lithium batteries.

If you're in the US I could consider helping you out. You can shoot me a private message if you'd like.

Medessec wrote: ↑

Thu Oct 30, 2025 1:32 pm

johnny1093 wrote: ↑

Tue Oct 28, 2025 7:55 pm

Re "rebuilding these batteries" is this something that you or anyone else here provides as a service? Or could you point me to a tutorial for this? If this is all too much of a hassle I might just look into buying another x61 that already has a functional battery...either way thanks for the info!

I'd imagine for X61 batteries right now, it'd just be me. I'm not sure of anyone else (besides kfzhu) who can do it, and kfzhu isn't trying to take on too many jobs like that right now. There are a few tutorials on resetting batteries like these, but it's not reliable at all, and it sounds like what you'd want is a full rebuild anyways (all new cells). Swapping in new cells isn't straightforward, you definitely need knowledge/experience with wiring, electronics, and the dangers of Lithium batteries.

If you're in the US I could consider helping you out. You can shoot me a private message if you'd like.

That'd be rad! I am in the US. Would love to chat more to see what might be possible. I'm locked from sending PM's at the moment since I'm a new user, so once that is lifted I'll send you a message. Thanks Medessec

Hello,

I have just registered on the forum.

I have three ThinkPad X61 Tablet laptops (two 7762 models and one 7763 model with a fingerprint sensor) for which I need to replace the batteries.

The three batteries I have are listed under the following reference numbers:
• ASM 42T5209 / FRU 93P5032 (Lenovo)
• ASM 42T5211 / FRU 42T4662 (Lenovo)
• IIMM536-B058Q2 (DLH).

I have searched everywhere on the Internet, but it seems that batteries of this type are no longer available for sale, therefore, they will need to be repaired.

Is there a tutorial available online?

Thank you.

tahitibub wrote: ↑

Sat Feb 07, 2026 4:34 am

Hello,

I have just registered on the forum.

I have three ThinkPad X61 Tablet laptops (two 7762 models and one 7763 model with a fingerprint sensor) for which I need to replace the batteries.

The three batteries I have are listed under the following reference numbers:
• ASM 42T5209 / FRU 93P5032 (Lenovo)
• ASM 42T5211 / FRU 42T4662 (Lenovo)
• IIMM536-B058Q2 (DLH).

I have searched everywhere on the Internet, but it seems that batteries of this type are no longer available for sale, therefore, they will need to be repaired.

Is there a tutorial available online?

Thank you.

Hello, I believe that me and my buddy actually made tutorials specifically for the X6xT and X20xT 8-cell batteries dealing with a Sanyo BQ8030 BMS that handles 4-cell 18650's as a pack and 4-cell 103450's as another pack.
The challenge however, besides the learning curve of a beginner in this, is how you are going to be able to obtain 103450's. You absolutely do not want to use old 103450 cells as I have not seen a single old 103450 cell that holds even 65% of its original charge. You will need brand new Molicel ICP103450CA or ICP103450DA prismatic cells specifically, and not the Panasonic NCA103450 that is of the NMC kind of lithium instead of LCO lithium that's used on these packs, which will result in subpar battery life (but good longevity).
It is in fact possible to rebuild, as fortunately I myself have attempted and succeeded in fitting 4 such new Molicel cells into a 4-cell (regular) X201 battery, the one with the flat bottom, and am using it right now to type this up.
But as a heads up, it is going to require a LOT of determination though... I've been teaching several fellow enthusiasts that has the need of these kinds of battery rebuilds, so far I've only succeeded in teaching two people who finally managed to rebuild a typical X6x or X20x battery successfully.

I don't believe I've put a writeup of the X60T/X61T 8-cell battery up yet, but I have just finished rebuilding one for a fellow enthusiast on Discord- a 93P5032 (which is an 8-cell).

As kfzhu mentioned, you do have the big hurdle of sourcing 103450s. They're a flatter, prismatic type of Li-Ion battery cell that is very uncommon nowadays, Molicel seems to be the only one making them and they aren't as cheap as 18650s- but the battery does use them. So you would need to get new ones.

But the 93P5032 in particular is pretty difficult as far as battery rebuilds go. The prismatics have a pretty tough layout that you have to line up pretty well to get it to fit perfectly, and although the 4x 18650s in the back of the battery pack are not so difficult to cell swap, you essentially have two packs in one. As a result, the BQ8030 ROM chip in this battery pack that watches over the cells has a pretty exotic data structure compared to almost all other Thinkpads at the time, even within the same gen.

I haven't seen any aftermarket battery packs for the tablets for the past several years... and even when they were available, I did buy one and it was pretty awful. The plastic didn't match at all and it hung off the rear of the laptop very awkwardly, and would de-seat very easily (I basically couldn't use the laptop on the go, it had to be on a desk).