LiPo charging module used as backup

battery-chargingbattery-operatedpower supplystm32

I am running small stm32/gsm module project and would need battery backup in it.
Is it possible to use cheap lipo charging module to do exactly that.

I would charge my battery through input terminals or usb, and be connected in the same time to battery. So if input goes away I get battery power.

Module is bought off eb..(no commercials):

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And uses this particular IC (datasheet)

Best Answer

Microchip's AN1149, "Designing A Li-Ion Battery Charger and Load Sharing System With Microchip’s Stand-Alone Li-Ion Battery Charge Management Controller", describes adding 3 components to a Li-ion charger in order to turn it into a battery backup system.

When battery-powered, the load is supplied through a wide-open PMOSFET. When line-powered, the load is supplied by the line through a single diode drop, and the battery is charged separately. The circuit is designed with the MCP73837 in the middle, but could very easily be adapted for the TP4056.