Ryobi Li-Ion Battery Pack by SoundDoc

Last crawled date: 3 years ago

While working on my Lack project my 10 year old Ryobi batteries which had been rebuilt a couple times just weren't cutting it anymore... So I went looking for a better option...
3D printer - Check...
ton of 18650 cells - Check...
I found a couple reference models on thingyverse that I've used before (like enif's battery case design ideas, and leaning on Simhopp's modeling work on the case I redrew it, modified it and built a couple extra parts to suit my needs...
In the end, this pack is ~50% the weight of a Ryobi NiCad case (600g vs 1kg) and has almost 4x the capacity (~1200mah NiCad vs ~5000mah (2x2500mah) LiIon). Images of the scale included, I didn't know it was going to be this light... (on the downside, my large drill now can tip it over lol, might have to add weight.
Let me state this here first:
LITHIUM ION BATTERIES CAN BE VERY DANGEROUS! Improper charging, accidental shorting of cables, etc... can cause them to catch fire and/or explode
If your not confident you know what you're doing, I'd go but another battery pack, its much safer. I'm not going to go into too much detail on the wiring for that reason, if you understand it, it'll be straight forward.
DO NOT charge ths pack on the factory charger. Why not? its designed for NiCad or NiMH packs, this pack also has no temperature sensing. Remove the cells and charge seperately in a proper charger OR, like I did, add balance leads and build a adapter to connect it to a proper LiIon charger. What happens if you do? See #1...
Comments greatly appreciated, let me know what you think!