Vintage Laptop CMOS Battery Leaks

Vintage laptops released in the 1990s are dropping dead fast. And it's all because of the type of CMOS batteries that they used. Unlike today when all laptops use Lithium CMOS batteries, most in the 90s used NiCad or NiMH chemistry packs, usually multi-cell packs made up of button cell style batteries. These could range from 1 to 9 cells, but they all have one thing in common: They leak nearly 100% of the time. In most laptops that used them, the batteries were placed near or directly on the main motherboard of the system, causing corrosion and chaos all around. Most of these batteries were made by VARTA and were green in color, but some brands used custom-made ones or others. Just look out for anything suspicious when taking a laptop apart - if it doesn't say Lithium on it, get it out!

The worst thing about these batteries is how few people know about them. Most who have a few old laptops will know that "hey, this series of Toshiba laptops has these weird green batteries that leak", or maybe another knows that Dell laptops have them. Few seem to know however, that nearly every brand used them. It's worse than an epidemic, it's a complete pandemic!

Affected Brands

It's pretty pointless to try to list them all. The 1990s saw hundreds of laptop brands, many who's designs were all based on ODM designs from companies in Taiwan. One laptop, affected with these batteries, may have been sold under 5 different little-known brands in the US. So that's to say, the only way to know if yours is affected is to take it apart and check for one of those batteries. Many laptops used these batteries as secondary suspend batteries to allow sleep-swapping batteries, and used a lithium coin cell for the CMOS. If you find a lithium coin cell, you may still have a secondary leaky battery lurking further inside. Check thoroughly.

Below I have included a list of brands and models known to use these batteries. This list is by no means exhaustive. I would HIGHLY ADVISE doing a full teardown on any vintage laptop you get your hands on that doesn't already have documentation online listing the CMOS battery type.

Brand Affected Models
AlphaTop Green753, Green751, possibly others
Apple PowerBook 150, 2400c, 3400c, no others.
AST Ascentia 910N, 950N, J-Series, P-Series, Advantage! Explorer 212/DX4-100, likely also the 900N, and likely others
AT&T Globalyst 200 (Same laptop as the Samsung NoteMaster 486P), AT&T Globalyst 250 (same as the NEC Versa M)
Chicony LT3400, others likely
Compaq LTE Lite, LTE Elite, LTE 5xxx, certain Armadas, likely others
CTX International EzBook 800 Series, others likely
Dell Latitude XP Series, C-series, Early D-series, various Inspirons, and more
Ergo/Brick NoteBrick, NoteBrick II, CD PowerBrick 2, others likely
IBM ThinkPad 700 Series, various others
Jetta Computers Co/Jetta International Jetbook 386SX, 486SLC, 486C2 Series, 486E1 Series, 6100, 6300CD/6300CD Plus, likely others
Micron Millenia TransPort, likely also the TransPort XPE, likely others
Nan Tan Computer Co. (FCC ID FMA Laptops) FMA8100, FMA3300, FMA3500 Series, FMA3530, VERY likely others
NEC Basically every 90s-era model
Samsung NoteMaster 486P, SENS 700, SENS 800, others likely
Sony Most VAIO models, even through the late 2000s. Sony used these batteries longer than anyone else.
Toshiba Nearly every model I know of, they even managed to fit one inside of the Librettos somehow!
WinBook 486SLC, SX/DX, XP, XP5, FX, likely also the XP5 Pro, possibly others
Zenith Data Systems Various
Any other brand CHECK YOURSELF!!!!!

Page last updated (MM/DD/YYYY): 05/20/2024
Update Reason: links and table updated

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