I should make a slight correction that the blue kit completely failed testing in multiple ways. It required sort of a "jump start" to operate correctly. Adding batteries live caused an unusual burning smell. It just wouldn't operate consistently or turn on charging when the button is hit. The red enclosure was AMAZING in testing though!
I used to vape a lot (to quit smoking) and 18650 batteries were used in the vapes. Not every battery is made equal. You can pay extra for higher quality batteries but i assume the difference is minor if you're just powering a phone charge or a light.
The big thing with vapes are running several hundred watt coils and that's hard to do at 4.2 volts. Those Murata batteries can do like 50 amps or something ridiculous like that and low end, off the shelf ones can do like 4 amps sometimes. Well 4x4.2v = not a lotta watts. But for 22 watts of fast charge using 8 cells in parallel, all adding amps cumulatively, you can put basically anything in them.
Wow, I haven't seen those with 20 parallel cells. With so many paralleled cells, a short will have the potential to burn the whole thing in seconds. Could you imagine putting cells in, and when you are up to cell #19, you suddenly put cell #20 in reverse by mistake? High-tech fireworks I would call it, lol. About charging to the weakest cell in the pack, it is not completely correct. The weakest battery will not have enough power to raise the voltage of the others enough to make the circuit "think" that it is fully charged, precisely because it is the weakest and all are in parallel. The more cells in parallel, the less possible such behavior is, and the voltage level will remain average among all cells, slowly rising up while charging. Remember that the only way for the circuit to "know" is the voltage level. With time, a damaged cell will also be a hazard. The current of all parallel cells will drain into any single cell with leaks or a short, making it extremely hot until it bursts, making it a real fire hazard. That is why, for example in my eBike, with so many parallel-series cells, each cell is protected with a fuse. Also, cells are spring-connected, not welded. First, movement may cause sparks under high loads, and second, high loads may heat the springs because of the natural resistance of spring materials. All these scenarios are worse if the cells have high-discharge capacity, like 10C, 20C, etc. Interesting video though. Thank you for it :)
This is great I've made exactly 23 diy powerbanks but i dont buy those kind of powerbank cases, im buying a fast charging board that has 22.5 watts fast charging and making pvc for its housing
AliExpress or ebay are the best, unfortunately. As for AC charging ones, they drop to DC anyway via a transformer but none really come to mind. Just get a mid-level USB charger cube that only does 5 volts, not fast charge, and then get that $18 xtar charger and just plug the USB into the charger cube at the wall.
I should make a slight correction that the blue kit completely failed testing in multiple ways. It required sort of a "jump start" to operate correctly. Adding batteries live caused an unusual burning smell. It just wouldn't operate consistently or turn on charging when the button is hit. The red enclosure was AMAZING in testing though!
I used to vape a lot (to quit smoking) and 18650 batteries were used in the vapes. Not every battery is made equal. You can pay extra for higher quality batteries but i assume the difference is minor if you're just powering a phone charge or a light.
The big thing with vapes are running several hundred watt coils and that's hard to do at 4.2 volts. Those Murata batteries can do like 50 amps or something ridiculous like that and low end, off the shelf ones can do like 4 amps sometimes. Well 4x4.2v = not a lotta watts. But for 22 watts of fast charge using 8 cells in parallel, all adding amps cumulatively, you can put basically anything in them.
Wow, I haven't seen those with 20 parallel cells. With so many paralleled cells, a short will have the potential to burn the whole thing in seconds. Could you imagine putting cells in, and when you are up to cell #19, you suddenly put cell #20 in reverse by mistake? High-tech fireworks I would call it, lol.
About charging to the weakest cell in the pack, it is not completely correct. The weakest battery will not have enough power to raise the voltage of the others enough to make the circuit "think" that it is fully charged, precisely because it is the weakest and all are in parallel. The more cells in parallel, the less possible such behavior is, and the voltage level will remain average among all cells, slowly rising up while charging. Remember that the only way for the circuit to "know" is the voltage level.
With time, a damaged cell will also be a hazard. The current of all parallel cells will drain into any single cell with leaks or a short, making it extremely hot until it bursts, making it a real fire hazard. That is why, for example in my eBike, with so many parallel-series cells, each cell is protected with a fuse. Also, cells are spring-connected, not welded. First, movement may cause sparks under high loads, and second, high loads may heat the springs because of the natural resistance of spring materials.
All these scenarios are worse if the cells have high-discharge capacity, like 10C, 20C, etc.
Interesting video though. Thank you for it :)
This is great I've made exactly 23 diy powerbanks but i dont buy those kind of powerbank cases, im buying a fast charging board that has 22.5 watts fast charging and making pvc for its housing
Where do you recommend purchasing these small set-ups ?
Also can I buy AC charging battery packs ?
AliExpress or ebay are the best, unfortunately. As for AC charging ones, they drop to DC anyway via a transformer but none really come to mind. Just get a mid-level USB charger cube that only does 5 volts, not fast charge, and then get that $18 xtar charger and just plug the USB into the charger cube at the wall.