I reverse engineered a ThinkPad Battery - and made a perfect clone

The IBM ThinkPad 701C is an iconic laptop. I go through every step to build a brand new battery. From modeling and printing a new case, label, building a new battery pack, recreating the terminal PCB and most importantly, cloning a once proprietary chip using an ATtiny microcontroller. All of the designs, code and instructions can be found at my site: https://701c.org and on Github at: https://github.com/hrushka/701c.org I've included timestamps below to help navigate, but I hope you enjoy this dive into a multi-skill build. Chapters: 0:00 - Introduction 1:09 - Cleaning and breaking down a 701C battery 4:32 - Shop Helper 4:40 - Modeling the case with Shapr3D 7:45 - Taking measurements for the terminal PCB 9:15 - Creating the debugger PCB with EasyEDA 10:13 - Assembling the debugger 12:30 - Testing the debugger with a known working Dallas DS2434 14:40 - Capturing data with a logic analyzer and Logic2 14:47 - Evaluating the data and stubbing out code 15:36 - Testing the cloned chip 16:15 - Designing the production PCB with EasyEDA 17:01 - Soldering 9 NiMH cells into a battery pack 19:18 - Recreating the label using Sketch 22:43 - Testing the labels for size and accuracy 23:14 - Printing the battery case with an Elegoo Saturn 2 8k 24:55 - Sanding and polishing the case using acrylic polish 26:10 - Testing & assembling the final chip and PCB 28:04 - Final assembly! 28:58 - The final test on a pristine IBM ThinkPad 701C 29:12 - Obligatory Doom cameo The epic tunes: Midnight Rider - The Big Letdown: https://www.epidemicsound.com/track/Z... Carbon - Truvio: https://www.epidemicsound.com/track/p... A Nebula Inside - ELFL: https://www.epidemicsound.com/track/n... Sunstorm - ELFL: https://www.epidemicsound.com/track/x... Inevitable You - Amaranth Cove: https://www.epidemicsound.com/track/y... Games in Color - Emil Axelsson: https://www.epidemicsound.com/track/c... Is This Love a Waiting Game - The Big Letdown: https://www.epidemicsound.com/track/6... Divergent - Ooyy: https://www.epidemicsound.com/track/w... Don't Lock Your Love Down - Kadent: https://www.epidemicsound.com/track/L... Music: All music licensed by Epidemic Sound