I recently saw a video where the tech had come into possession of several cell phone batteries. He demonstrated a little ciruit board that was about half an inch square, at most. The ciruit board had a usb micro port on it and once connected to the battery it allowed the battery to be recharged or used as a power bank. I would like to know what that circuit board is. Tried asking in the comments for the video but I've not had any response. He had a strip of these circuit boards that he could break one off of and connect it to the battery.
Considering the number of old cell phones I have laying around this might be quite useful.
If you do a search on your favorite shopping site... Amazon, eBay, AliExpress, etc for "1S USB charger Arduino". Typically adding Arduino to any search will get you electronic hobbyist type stuff. I have a bunch of these, but now, you might find some with USB micro or fast chargers using USB-C.
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Hi @witchdoc 59,
Maybe it was something like:
https://www.aliexpress.com/item/1005001621934354.html
Depending on the battery and the USB power source, make sure the charging current is kept within the battery capability ... many of these small boards expect to be connected to a 18650 cell which is considerably larger (typically 2-3 A-Hr) than the battery fitted to the smaller phones, and hence an 18650 can typically tolerate a higher charging current.
I suspect the charging current will be set by a resistor on the board, which in princple can be changed, but you will need to do some detective work, and maybe a bit of luck, to figure it out.
Bill (@dronebot-workshop), our generous forum provider, has made an excellent video on some aspects of lithium batteries, albeit generally higher current and capacity than those found in mobile phones.
https://dronebotworkshop.com/lipo-safety/
Keep safe .. an overheating lithium-ion battery is a very a dangerous beast!
Best wishes, Dave
@witchdoc59 The TP4056 is what you want, but also watch a Youtube video or two on charging safety. Best is to use a charge bag as these kind of batteries can explode and result in very nasty fires if mishandled.
First computer 1959. Retired from my own computer company 2004.
Hardware - Expert in 1401, 360, fairly knowledge in PC plus numerous MPU's & MCU's
Major Languages - Machine language, 360 Macro Assembler, Intel Assembler, PL/I and PL1, Pascal, Basic, C plus numerous job control and scripting languages.
My personal scorecard is now 1 PC hardware fix (circa 1982), 1 open source fix (at age 82), and 2 zero day bugs in a major OS.
@zander Thanks for the quick reply. I work as a computer tech for a community college. I've had to tell several people that their laptops have become time bombs. It's funny how someone who moments before will say they can't possibly do without their laptop for the next 6 month will suddenly turn it over immediately when they realize it's a bomb.
@davee Thanks everyone for the fast responses. Found this USB-C version which apparently has overcharging/undercharging protections.