Mini Lithium Charger and Booster – 5V 2A – with Battery Gauge

(1 customer review)

CAD 5.95

Need more? Ask for a quote.

Out of stock

SKU: 26543 Category:


A tiny module to charge a lithium cell (4.2V max.) with a powerful current of 2.1A from a 5V power source.

4 LEDs show the charging level in 25% steps.

The module also contains a 5V booster converter with a maximum output current of 2.1A.

The output is activated automatically as soon a load is connected but turns off if the load is less than 50mA. The output stays on continuously if the load exceeds 50mA. It is also possible to trigger the output by pressing a small button on the module or apply GND level to the contact pad marked with “key”.

An application can be for example an uninterrupted power supply for a microcontroller project, where the battery is recharged from time to time.

It is very easy to integrate the module in your circuitry since input, output and battery use the same GND pin. Just cut the 5V power supply line of your device or circuit, connect the module with its input “VIN” and output “OUT +5V” to the 2 open wire ends of your 5V supply voltage, connect the lithium battery [+] to the “BAT” pin on the module, and the battery [-] and the ground level of your circuit to the “GND” pin. That’s it.

The dimensions of the module are 25 x 16mm, the weight is 2.6g

Additional information






Does not apply.

Model Number




1 review for Mini Lithium Charger and Booster – 5V 2A – with Battery Gauge

  1. m.p (verified owner)

    I’m always leery about Li-ion batteries because they hold a lot of energy and if they’re mistreated they can be damaged or start a fire. This little charger/booster module looked too good to not try, though – the idea of powering a microcontroller or SBC off a single, commonly available 18650 was very tempting.

    I hooked it up yesterday with an old 18650 that I had kicking around and have been running an old Raspberry Pi B at 100% CPU load until the module cut off the power to protect the battery from discharging too much. The four LEDs that indicate the charge remaining are very bright and when the battery is almost drained the 25% LED blinks. Neither the battery nor module got warm, and the Pi stayed up and on the network until the module shut itself off.

    Charging the battery has so far worked well, too. The battery stays cool, the module is somewhat warm to the touch, and the Pi is running while the battery is also charging. Like most popular USB battery packs, the LEDs blink to show what level the charge is at.

    With no load attached, you can turn the module on by pressing the button. It also starts up if it detects a If it doesn’t detect a load (or if the load is removed), it will shut down after about 35 seconds.

    A few things to note, though:
    – While it seems like powering a device and charging the battery at the same time works, I’ve only been using it at currents of less than 1A.
    – If a device is being powered by the battery, attaching the module to a 5V supply to charge the battery doesn’t seem to cause any problems, BUT disconnecting the 5V supply causes a brief sag on the output that may cause problems with the device you’re powering (i.e. an SBC).
    – The module uses a low power mode to detect whether there’s a load connected, and once it detects the load, it puts 5V on the output. This can cause problems with devices that need a particular voltage to start up (again, some SBCs).
    – As the product description says, there is a minimum current draw required to keep the module from thinking there’s nothing connected to it. Many small microcontroller projects may not pull enough current to keep it running (although it’s usually a lot easier to make a circuit use more current than less, so that shouldn’t be much of a problem.

    All of this to say that so far I’m very pleased with this module. It’s inexpensive, easy to use, does what it says, and seems to do it pretty well. I can see a lot of uses for these!

Add a review