I recently bought and fixed two beautiful Sony Discman players, the D9 and D15. However neither came with the internal rechargeable battery and I didn't like the idea of being tethered to a wall adapter so this is my attempt at making a cheap replacement (there are a few sellers online who do similar mods but charge stupidly expensive prices for what is essentially a <$20 bodge).<="" body=""></$20>
Just a quick update after using my battery for a few weeks. I've yet to do an actual capacity test on the used 850mAh ipod battery I pulled for this project so I'll have to update the real measured capacity here when I do. However, as a rough measure of battery life, one full charge seems to get me through around three 40 minute albums listening at low to mid volume with minimum track skipping/fast forwarding. So roughly 120 minutes of play back per charge. Definitely not great, but this is actually right on par with Sony's claim that the original rechargeable would run for two hours. My guess is the 850mAh battery I pulled from my 2003 ipod video is quite diminished so I'll buy some new replacement batteries to make sure I am getting their full capacity.
Finally, I wanted to mention that I've added all the design files to the project page (or click here https://hackaday.io/project/165088-sony-discman-diy-lipo-battery/files). This includes the 3D printed case base and lid (I printed in PLA at 0.2 mm layer height, taking approx 40 minutes to complete) as well as the small battery contact pcb (courtesy of JLCPCB, 0.8 mm board thickness and ENIG gold plating on pads to ensure low resistance contacts and resistance to corroding, though HASL should work fine as well). I provide these files under the following conditions: I am not responsible to any damage from their use, feel free to modify them, and finally all I ask is attribution (link to my youtube channel and this project page) if you tweak them and repost somewhere online. Other than that go nuts!
To start off, thanks to JLCPCB for sponsoring this project as well as providing pcbs to get the ball rolling. JLCPCB Prototype for $2 (Any Color): https://jlcpcb.com
After fixing my two beautiful Sony Discman players the next natural progression was making rechargeable batteries for them since oem ones are difficult to find, expensive, and barely work given that they are nearly 30 years past their prime. Requirements for the design include: usb rechargeable, higher capacity than the originals (850mAh vs 550mAh!), easily/cheaply 3D printed, and drop in replacement. So let's get to work seeing what I came up with and the design iteration process.
The parts are all cheap and widely available, consisting of a usb lipo charger board (my affiliate link: https://ebay.to/2DnGEj4), an ipod video battery (https://ebay.to/2KSoYlN), and finally a simple tiny metal contact pcb (board files will be released shortly). All that is necessary to wire everything is to attach positive of the three parts together and attach negative together, it is that simple. Physical construction is just a matter of hot gluing the components into the plastic 3d printed shell (stl files will be released shortly) and gluing or taping it all shut. Printing the case takes around 45 minutes, and assembly should take no more than half an hour.