24v 18650 APC UPS Hack

Here is the video about the 24v UPS 18650 Hack. Shows how to build a 7s9p pack (kinda). I used 1900ma cells at random. I plan on rebuilding the pack and make it more balanced. This is basically a scaled down version of my Power Wall. Fun to mess around with until I get the Power Rack going.

* The nice thing about putting the cells inside the UPS shell is that if something goes wrong with the cells and they ignite, it's already in a steel container.
* Interesting thing about using the vice and drill to straighten the wire is the wire seems to get stiffer.
* I like how you do your fuse wire soldering. Just start at one spot and then just basically connect each cell until you get done, then come back and cut out the ones you don't want connected :thumbs up:
* For the busbar->stranded wire connections, you could take the busbar wire and put it inside the strands and then compress the connector around the joint.
* Wouldn't unplugging from the wall be "Dis-Contact"?
* I agree with daromer with putting a BMS with it as well. Especially since the parallel strings are getting off balance. However, having them close with base mAh might help with that

Overall, great work!!

His videos caused me to buy 2 things.
Tin coated fuse wire, it bends so much easier than the wire I have.
200 watt soldering iron.

Things have speed up 10x in soldering my packs now.

Ya a good soldering iron is a must

Don't forget to clean and tin the tip when turning off, will prolong the life significantly

Scepterr said:

Don't forget to clean and tin the tip when turning off, will prolong the life significantly

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YES!!! Most important step. Every time I set the iron back in its holder I wipe clean then add a lil dab of solder. Then when I grab it to use again I wipe it and apply another dab then set on whatever you are soldering.