Beginner’s guide to building safe 18650 batteries
Teaching Tech
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Teaching Tech is a YouTube channel dedicated to providing quality content that will help expand your technology related skills and knowledge. As a qualified Industrial Designer and Primary/Secondary school teacher, my expertise is very broad. The channel features tutorials on 3D modelling, 3D printing, laser cutting, CNC machining, coding, robotics, electronics and graphic design. I also have other fun tech which I review and feature. I pride myself on my integrity and can guarantee only unbiased, unpaid reviews and opinions. The content of my videos is something you can trust to help form your opinion. Finally, I love doing things on a budget. This means I can pass on some great tips that can get you started for minimal outlay. Support me on Patreon: http://www.patreon.com/teachingtech As an Amazon Associate, I earn from qualifying purchases. Contact is through my website: https://teachingtechyt.github.io/contact.html Michael -Teaching Tech Creator
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Re-upload: This is a re-release addressing early feedback from the original video, in which I referred to all of the lithium batteries as Lipo, even when 18650s are most commonly Li-ion in chemistry. Pictured in the video and linked in the description was a website about the differences between various lithium batteries, but clearly me constantly using the term Lipo was confusing and misleading. Therefore, I present this minor edited version to correct the problem. My apologies for the original error and I hope this tweaked version can be the informative video I originally set out to make. Last year I discovered the world of custom 18650 battery building. You take li-ion cells, new or recycled, and build a battery to your exact project specifications. There’s a lot of conflicting information out there and many potential safety hazards. In this video I compile many weeks of research into an introductory guide for building batteries safely. Please pay close attention to the safety warnings and tips in this video. Always consult a professional, not just onlines videos and forums, before building a custom battery. This video is solely intended to get you up to speed before you check your plans with a professional. In a future video, I will be building a high voltage, high current custom battery to power a small EV. 0:00 Introduction 0:51 What are 18650s? Tesla 18650 battery: https://www.evwest.com/catalog/product_info.php?products_id=463 2:04 Voltage, current and capacity: series vs parallel Lithium battery FAQ: https://www.batterypowertips.com/difference-between-lithium-ion-lithium-polymer-batteries-faq/ 4:39 Example battery calculations Battery calculator: https://power-calculation.com/battery-storage-calculator.php 7:28 How to shop for 18650s How to spot fake VTC cells by Mooch: https://www.youtube.com/watch?v=zfEp353cT1M Tech Around You in Aus (recommended by my personal experience): https://www.techaroundyou.com/ Second Life Storage cell database: https://secondlifestorage.com/index.php?pages/cell-database/ 10:15 Testing and managing 2nd hand 18650s Opus charger: https://amzn.to/3EOQ43S Repackr website: https://www.repackr.com 11:09 Building battery frame Modular cell holders on Amazon: https://amzn.to/31u6rFs Example cell holder on Thingiverse: https://www.thingiverse.com/thing:1452396 11:44 Nickel joining strips How to identify pure vs coated Nickel strips: https://www.youtube.com/watch?v=wlf47SZoNSQ Matador’s nickel strip rating chart: https://endless-sphere.com/forums/viewtopic.php?f=2&t=98849 12:54 Spot welding the cells together K-Weld spot welder: https://www.keenlab.de/index.php/product/kweld-complete-kit/ 14:41 Solder/spot weld less option: VRUZEND VRUZEND weldless 18650 kit: https://vruzend.com/product/vruzend-battery-kit-v2-0/ 15:08 Balance leads, terminals and charging Rosin flux paste: https://amzn.to/3FYuLhJ Fish paper: https://amzn.to/3mTsVXO Kapton tape: https://amzn.to/31s8Znx 17:31 Finished 3D printer battery 17:51 BMS - Battery management systems Daly BMS website: https://dalyelec.en.made-in-china.com/ 18:41 Conclusion Previous portable MPMD video: https://youtu.be/Cv5pEcBI5Hw Endless-sphere forums: https://endless-sphere.com/forums/ Reddit 18650 sub: https://www.reddit.com/r/18650masterrace/ Buy quality and affordable filament from X3D. Buy 3, get 1 free and a free sample pack with every order: www.x3d.com.au Get Quality Resins from 3D Printers Online. 5% off storewide for Teaching Tech subscribers [Code: tech5] https://3dprintersonline.com.au/ Take a look around and if you like what you see, please subscribe. Support me on Patreon: http://www.patreon.com/teachingtech
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