If you would like some feedback in whatever is going on there, please explain what the problem is and what you want to know.
this post was submitted on 19 Jan 2025
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I connect powerpack to the battery terminal
Then this is not safe.
The maximum charge voltage for a lithium cell is 4.2V while USB will provide 5V. It may work for a while, it may fail in a safe state or something gets hot and burns.
actually the powerpack have varied output (4.5v5a - 12v1.5a), I'm not planning to use this for real I just wanna see if it work or not since the powerpack and phone battery output the same DC current
What are you trying to do
the battery died and I connect powerpack to phone's battery terminal
Props for having the guts to take a lithium battery apart so you could wire the usb cable to the bms.
I guess it's sort of safe in that the bms would shut itself down if the voltage is too high because it thinks the battery is overcharged, but I still wouldn't recommend using it in this config as I'm sure the usb port can't provide the same amount of current as the original phone battery, so the phone might shut down.
Here's a safer way to do it if you want to run that phone without a battery
I'm not planning to use it for real since I didn't trust it myself and thanks for the link I'll have to try it out later
Spicy pillows are not safe, remove them from your equipment
It looks like this person's phone battery died so they skipped the battery altogether - instead they wired a charger directly to the phone, eliminating the need for the battery.
Along with your comment it looks like you are powering a phone with a power bank by skipping the phones battery and connecting directly to the phones battery terminal?
5V may be too high of a voltage for your phone as the phones lithium battery would have otherwise provided 4.2v ish but youll need to find out.
If you directly connect to the charge controller input does it still work or does it complain that there's no battery?
It seems to be working, but the phone is expecting a 4.2V or 4.35V max input on the battery terminals and USB is 5V. Maybe that power bank has a lot of voltage drop or a poorly regulated output so the voltage is lower.
this powerbank can output varied output (4.5v - 12v) and it's a fairly high quality powerbank
USB-A will be 5V though.
It supports those, but voltages other than 5V will only happen when an appropriate handshake happens. Just a USB-A cable to bare wires has no handshake and will be 5V.