Gregory's Serveri made a replacement standby battery pack for my Thinkpad 700C!
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then i put down a little 3d-printed plastic spacer, and then the first nickel strip goes on top of that. now you see the trick. the first tabbed cell goes positive terminal down. the tab sticks out in the groove in the front. then the other cell gets arranged in the little trough that holds it at the correct angle. then i bend and mush the cells together after welding, and line it up for the last cell. the trough has enough room to support 2 cells. i didn't grab a photo of me welding the solder tabs, but it's a similar process. lastly i put a length of heat shrink over the whole thing to hold it all together and insulate it. sadly the precut length of heat shrink is just a tiny bit short. oh well. quick fit check, and it works! these cells have a button on the end that is 1mm longer than the original, so i had to flip the battery pack around to get it to fit.  @tubetime ..yeah, I had to do the same thing to replace the aging backup battery in my HP8665A sig gen.  @tubetime I need to replace the "secret” internal NiCd in a Palm Vii and those cells look like they might be close to the right diameter. Can you tell us the dimensions? @tubetime Thank you. The Palm battery is 10 x 61 (including the nickel tabs on the ends). I'll take the wrapper off mine to see how it is composed. @tubetime Very coincidentally, I recently discovered these cells when I was looking for something non-lithium for a small wearable. @cd0 yeah it is giving me ideas. you can also get small lithium cylindrical cells meant for vapes.  @tubetime You know, props to whoever was sourcing components for IBM back then that those things didn't leak all over the place. Hopefully your new ones keep their act together as well.🤞 |
here's the original battery.