I wouldn't think the AAA batteries would be anywhere near powerful or durable enough. Pretty sure they originally used 18650 Li-ion batteries. Bit more expensive, maybe €3 each for good used and tested batteries, but they will last years.

debs3759 wrote on 2020-07-19, 01:06:

Pretty sure they originally used 18650 Li-ion batteries.

I will clarify that this is about 1992-1996 486/P1 laptops which use about 20 watts, and had only ni-mh batteries. The format was originally 4/3A (17670). Modern AA batteries work very well because I'm already using them in one pack, but I wonder if smaller ones would work at all. I'm afraid that I will put new cells in 10 laptops, let them sit in a box for 5 years and all batteries will be dead by then.

Hmm Waiting 5 years to power up and have rechargeables still having a good charge is a pipe dream (just my opinion). I think you can get away with the AAA or AA but AAA supply about 1/3 overall wattage. To me the 5 year span is extreme, if 2 or 3 year they might still be partially charged but you said 5 years. Wow that is expecting a lot, not saying it may not be possible but I charge my old Tosh and Vostro about once a year. Would never think of sitting 5 years and expect the batteries to have any charge at all.

Horun wrote on 2020-07-19, 02:03:

Hmm Waiting 5 years to power up and have rechargeables still having a good charge is a pipe dream (just my opinion).

That's why I would like to install battery holders, i wouldn't put any batteries there and keep them empty, but if they would be needed at any point in the future, I would just open the battery pack and put 12 batteries there without the need to solder anything 😀 if that's not a good idea maybe it's better just to not use the batteries at all, the truth is that USB-C PD powerbanks with special adapters can power these laptops just fine. But I will check if there is any possibility of fitting AA battery holders, they should work OK if they fit.

BTW i have three li-ion batteries for Toshiba Libretto with manufacture date 1997-9 and they still work with almost an hour of runtime.

Hey, quite a necro-bump but I've been doing some testing with this lately. I recently got a Toshiba T2130CS - I'm pretty fond of it despite its vintage, the screen is 'quaint' and the battery life is 'interesting'.
When I got the laptop, its battery pack was completely non-operational and all NIMH cells had corroded / split. I have the NIMH battery pack from a Toshiba 110CT that sadly did not surive on the 'operating table'. Despite this, while the original pack was completely gone, while the 110CT's pack could get around 2 hours of usable battery life.

I decided to clean up and rebuild the corroded NIMH pack with some AA eneloop cells. Trying out the battery pack made from spring-held AA batteries, operation was around 30 minutes with good Eneloop cells. I think that a combo of the higher current draw and the current limits of the 'junk' battery boxes I was using, dropped it below an operable level (11.3v) very quickly. I think that's cell > cell voltage drop rather than the whole pack. But I have both a full 10x1 AA battery pack on the way, along with a spot welder and some 'amaloop' cheap battries. I'm keen to see which of the two performs better under good conditions. Really hoping that the AA cell in battery holder works well because, same as you, I don't want to permanently attach 10x cells to a single laptop / battery pack type.

Thermalwrong wrote on 2021-11-26, 04:34:

Hey, quite a necro-bump but I've been doing some testing with this lately. I recently got a Toshiba T2130CS - I'm pretty fond of it despite its vintage, the screen is 'quaint' and the battery life is 'interesting'.
When I got the laptop, its battery pack was completely non-operational and all NIMH cells had corroded / split. I have the NIMH battery pack from a Toshiba 110CT that sadly did not surive on the 'operating table'. Despite this, while the original pack was completely gone, while the 110CT's pack could get around 2 hours of usable battery life.

I decided to clean up and rebuild the corroded NIMH pack with some AA eneloop cells. Trying out the battery pack made from spring-held AA batteries, operation was around 30 minutes with good Eneloop cells. I think that a combo of the higher current draw and the current limits of the 'junk' battery boxes I was using, dropped it below an operable level (11.3v) very quickly. I think that's cell > cell voltage drop rather than the whole pack. But I have both a full 10x1 AA battery pack on the way, along with a spot welder and some 'amaloop' cheap battries. I'm keen to see which of the two performs better under good conditions. Really hoping that the AA cell in battery holder works well because, same as you, I don't want to permanently attach 10x cells to a single laptop / battery pack type.

I have 2 Toshiba laptops, a 430CDT and a 445CDX. Both have Li-ion batteries and both still work. But I know that won't be the case forever and I have already started thinking about how I am going to address the problem. I think I am likely to just make all new packs using a 3D printer and fill them with li-ion cells. I figure I can just cannibalize a battery charger and put that in the pack. It will take some modding to pull 5V off the power supply for charging and some custom electronics but I think it will be well worth it to have compact, portable 486 and Pentium gaming machines. I should be able to get like a 10-12 hour battery life, given the storage density of modern cells and the low power requirements of the hardware. The pack in the smaller, less hungry 445CDX (DX4-100) is only 3600mAh, about the capacity of one high density 18650 these days, 🤣. I will probably have to use a different size though, for the 445 because the pack is thinner.
Here is a link to a great source of info on old Toshiba laptops:
http://www.minuszerodegrees.net/manuals/Toshiba/Toshiba.htm
They have the actual maintenance manual for your T2130CS, which has some electrical specs listed. Another useful thing to be found here is the tsetup.exe utility which will allow you to access the BIOS.

The early Toshiba laptops with lithium ion are quite a different problem - they unfortunately use a unique cell type. That's 17670 or "4/3A", the same size as the older NIMH cells - completely unavailable as new cells now. 18650 are too big to fit without damaging the battery casing.
The best lead I've found for replacement cells, since I want my Librettos to be portable again, is the 16650 cell. Those can be found in some Acer laptop packs "Acer AL14A32 Aspire E5-571 511 16650 3S2P 6-Cell". I haven't bought one yet to check, but plan to when my mini spot welder gets here. Then I should be able to make 2 good packs for my Libretto 70CT & 100CT.

When it comes to Lithium Ion packs, in my opinion those can only be safely made into battery packs by replacing existing cells and using the existing BMS (battery management system) from the original packs.
These are old laptops so their BMS are more likely to tolerate the cells being removed and replaced, a newer BMS will just permanently turn itself off when that happens, and I just ruined my nice Bose bluetooth speaker that way to find that out.

The problem to consider with replacing the electronics with something like a power bank, is that the laptop will want to put voltage into the battery terminals to charge it. Maybe a diode could make that safe but my preference is to take the simpler route and just work with the existing electronic system that was designed with these early lithium ion packs.