Can/will a lithium ion cellphone battery that can be charged at 2 amps safely discharge at 2 amps if used as a power source for a power bank? (Samsung galaxy S4 mini battery in particular)


I plan to convert a wired headset into a Bluetooth headset. I will use a Bluetooth PCB that requires 5V input and an amp (PAM8403) that also requires 5V.

I will use a power bank pcb to deliver 5V to reach component. The power bank requires a 3.7V lithium ion battery and outputs 5V 1A & 5V 2.1A.

Would a battery made for cellphone work safely in this build? The battery can output 3.7V. I can't find the discharge current for the battery anywhere but I know it can charge at 2A.

Finding a legitimate 18650 battery online is proving difficult so I'm considering a using phone battery.

  • \$\begingroup\$ I plan to use the battery to power a Bluetooth receiver board and a small amp. The (3.7V) battery would be connected directly to a power bank pcb which will output 5V at 1A and 2A simultaneously. The power bank pcb accepts 3.7v input. \$\endgroup\$ – user3697242 Apr 17 '18 at 10:46
  • \$\begingroup\$ Was that supposed to be a reply to my answer? Or an addition to the question? If that was a question update, please edit the question rather than add a comment. Also, you are still lacking the information I mentioned in my answer \$\endgroup\$ – MCG Apr 17 '18 at 10:50
  • \$\begingroup\$ Then my answer stands. Yes, you can use it, but it won;t last long \$\endgroup\$ – MCG Apr 17 '18 at 13:00

Really a bit more information is needed, what is the application? What voltage do you need? Can the battery supply that voltage etc. So really, you need to think about it a bit more. However, I will address your concern about using the battery at 2A. What you need to do is look at the mAh rating of the battery. This one HERE is the official battery of the S4 mini. You will notice that it states 1900mAh. This means it can run at 1900mA (1.9A) for 1 hour. Less if you take into account losses incurred during discharge etc.

So if you were to use this battery at 2A, it would last you approximately 55 minutes, but realistically it would be quite a bit less than that.

So to answer, yes, you can use it, but make sure you have a bit more of a think about all the requirements, not just current consumption!


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