I want to power a device with up to 4A at 5V from a single-cell LIPO battery of 3.7V 5000mAh and be able to charge it. The idea is to have everything packed up inside a case, so I don't want to rely on an external charger and instead be able to charge it from USB2.0.
To convert the power from the battery to the device (from 3.7V to 5V), I plan to use a boost converter capable of supplying up to 4A ouput current (such as a XL6009 converter).
However, I don't know how and where to add a charger (such as this one, or any other one that would fit).
I'm not very versed in electrical engineering. Please help :) Thank you.
EDIT: I found this charger which allow to charge the battery while offering a direct output connection to the device. How can I be sure that the output connection can support the ~6A @ 3.7V current drawn from the battery ?