I've little experience in the nitty gritty of electronics so am looking to inexpensive modules that can help me achieve my goals. Specifically I have ESP32 (3.3v) and Arduino Nano (5v) projects that I would like to power with LiPo (3.3v) batteries. Ideally, the project should be able to be powered by the battery alone, and still continue to operate when plugged into a USB power source, while also charging the battery.

I'm trying to understand whether a TP4056-type charging module like this one on AliExpress (https://www.aliexpress.com/item/1005001621934354.html) will fit the bill (charging the battery AND powering the project) or whether there are some serious gotchas that I need to consider?

I've read many questions on this SE and most of the answers get a bit too technical for me. I do want to learn the nitty-gritty, but for now I just want to get my project off the ground and it seems a fairly common use case.

Update: generally USB power banks are too large / overkill to be an option for the very small footprint, low power projects I have in mind - plus they tend to be expensive in comparison to a $3 module and a $5 battery.

  • \$\begingroup\$ What does the data sheet tell you that gives you confidence or worries? \$\endgroup\$
    – Andy aka
    Commented Feb 11, 2022 at 17:38
  • \$\begingroup\$ Batteries that go boom are not a project you want to tackle without the nitty gritty. Also lipo batteries are not 3.3V. A usb power bank and a regulator would be preferred until you learn the technical stuff. Just find one that has trickle charge or doesn't power off if the current is too low. \$\endgroup\$
    – Passerby
    Commented Feb 11, 2022 at 19:38

1 Answer 1


A quick-and-easy solution would be to use a USB power bank for 5V. This deals with all the charging and protection issues, and boosts the LiPo output.

For your 3.3V projects, a linear low-dropout regulator to take 5V down to 3.3V might be the easiest solution, if not the most efficient. A DC-DC module that has good low-power efficiency would be better.


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