A hefty portable power bank is a handy thing to DIY, but one needs to get their hands on a number of matching lithium-ion cells to make it happen. [Chris Doel] points out an easy solution: salvage them from disposable vapes and build a solid 35-cell power bank. Single use devices? Not on his watch!
[Chris] has made it his mission to build useful things like power banks out of cells harvested from disposable vapes. He finds them — hundreds of them — on the ground or in bins (especially after events like music festivals) but has also found that vape shops are more than happy to hand them over if asked. Extracting usable cells is most of the work, and [Chris] has refined safely doing so into an art.
Many different vapes use the same cell types on the inside, and once one has 35 identical cells in healthy condition it’s just a matter of using a compatible 3D-printed enclosure with two PCBs to connect the cells, and a pre-made board handles the power bank functionality, including recharging.
We’d like to highlight a few design features that strike us as interesting. One is the three little bendy “wings” that cradle each cell, ensuring cells are centered and held snugly even if they aren’t exactly the right size. Another is the use of spring terminals to avoid the need to solder to individual cells. The PCBs themselves also double as cell balancers, providing a way to passively balance all 35 cells and ensure they are at the same voltage level during initial construction. After the cells are confirmed to be balanced, a solder jumper near each terminal is closed to bypass that functionality for final assembly.
The result is a hefty power bank that can power just about anything, and maybe the best part is that it can be opened and individual cells swapped out as they reach the end of their useful life. With an estimated 260 million disposable vapes thrown in the trash every year in the UK alone, each one containing a rechargeable lithium-ion cell, there’s no shortage of cells for an enterprising hacker willing to put in a bit of work.
Power banks not your thing? [Chris] has also created a DIY e-bike battery using salvaged cells, and that’s a money saver right there.
Learn all about it in the video, embedded below. And if you find yourself curious about what exactly goes on in a lithium-ion battery, let our own Arya Voronova tell you all about it.
Applause, Applause!!
Thankfully those disposable vapes are getting banned in Europe. At least in the UK and France. Crazy waste.
Hopefully we get a tax system that would have made it uneconomical to produce in the first place. Blue sky thinking I know.
I’ll take blue sky over fascism any day.
Don’t you see that banning disposable vapes is compatible with a Fascist government? Words have meanings; it’s wrong to use “Fascist” to mean “something I don’t like.”
Communism over fascism? Two sides of the same coin.
Here in Australia they have completely banned vapes (with a few limited exceptions and you have to go to a pharmacy for that). Still a thriving trade for the stuff though unfortunately (wish governments would do more to shut down the shops selling it)
Must be a smelly job to get them out. That withstands me to collect them and use them.
I used to vape and would save every cell. Now that I’ve quit, sometimes the process really chokes me, and even the cells I gathered earlier still smell. Once you put them in an enclosure they don’t smell anymore.
So you’ve never tried it?
I’ve only dismantled two and it was no problem at all.
Granted both where mint flavored (I think) but as long as you don’t dismantl the part that actually contains the fluid you should be fine.
The part about changing one cell out when they all should be suspect and are ready to recycle only! Though the cells have only one cycle the standards of manufacture and their source make this a really scary proposition. Yes, ban them if not rechargeable and refillable.
I’m not sure why cells are being put in series. This just leads to balance problems, especially when assembled from non-matching cells. Is there some limit to how many you can put in parallel? All the power banks I’ve disassembled had all of the cells in parallel, and a single small PCB that has both the buck charging circuit to get down to 4.2V, and the boost output circuit to get back up to 5V.
The limit to parallel is conductor size when shorted or imbalanced unless you prefer battery fires.