Saturday, September 17, 2022

Refurb weekend: New batteries for the Palm Pilots

Everything portable has a battery, and every portable thing's battery dies. This is bad on earlier PalmOS devices that lack a non-volatile file system because they'll lose their data and you'll lose your mind. Fortunately many of my stable of Palm Pilots and other PalmOS devices use regular old batteries (like my original USRobotics Pilot 1000 and Handspring Visor Deluxe); of my rechargeable units, the AlphaSmart dana has a replaceable battery (I have multiple spares, or you can use regular batteries), and so does the Palm Centro, which has a non-volatile file system to boot. This is another reason why those two are my favourite Palm devices.
For many others, though, they have an internal battery pack that will require you to crack the case and disconnect it. Even though some of these PDAs are decades old, there is still a healthy parts market for them, and happily they generally use standard LiPo or Li-Ion cells in standard sizes. These eBay specials here even came with screwdrivers and spudgers. If you can't find an exact replacement, be sure to keep the connector from the old one so you can attach it.

A few Palm devices are relatively hostile to repair; for example, my T|X's battery is soldered in. This was also the highest priority replacement since the old battery was swelling and starting to distort the rear case. I forgot to get pictures of it but wary of my soldering skills with a small circuit board, I clipped the leads of the old pack and just twisted the wires on from the new one with strategically applied Kapton tape to keep everything apart.

That left the Zire 72, which wasn't holding a charge for long, and the m505, which wasn't holding a charge at all.

Unfortunately, the Zire 72 is another repair-hostile device. Getting the back off requires not only removing the obvious screws in the lower corners, but then peeling back the label (!) to expose another screw on the bottom tab of the camera grille. Alternatively, just cut a little hole there in the label to get to it, since we're all way out of warranty anyway. With that screw removed, use a nylon spudger to pry off the grille without bending it (it's stuck on with adhesive strips) and remove two more screws at the top.
Use the spudger to undo the remaining clips around the unit and it comes apart in two halves. Be sure not to lose the pad with the front buttons, which aren't attached to anything; I managed to get them to flop into their apertures on the other side. Don't use a sharp metal object to separate the clips or you may nick the exposed clear cable to the digitizer, rendering your unit unusable. You can also see the camera connector, the front connector (which you can leave on, or gently remove with the spudger; just press it back on to reattach), and the ARM CPU (an Intel PXA270).
The Z72's battery isn't soldered in and has a connector you can gently pull free with needlenose pliers. Once the connector's off, however, you'll need to wedge it out from the glue holding it in (spudger encore). I replaced it with an 1100mAh 3.7V part sold specifically for it with the correct connector; it's keyed and you just push it on.
When putting it back together, make sure the light pipe for the power light is on its little pegs.
Also, while the front button pad needs to be watched and aligned back into its holes, mind the side button as well — as I didn't after closing it up.
By comparison the m505 was rather easier. This took a 1000mAh 3.7V lithium polymer battery, and was also sold specifically for it with the connector already wired up. Just remove the rear screws and work open the clips if needed. Do not work the spudger into the SD card slot; that stays attached to that particular side. This battery was unfortunately swelling a little also, so good thing we were in there, though it was also glued in and needed to be pried out too.

All the units recharged briskly and held a good charge for several rounds of Solitaire and surfing Gopherspace. More ideas coming for apps and they'll be ready to test them when I do.


  1. Enjoying leafing through your Blog archives. Found you via Ken Sheriff's recent Twitter thread


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