I have adapted a load sharing circuit that was posted online that uses a MCP73831 to charge a Lithium battery. In my case I wanted to to use the TP4056DW01A and connect its output to to a boost converter.
Under full load I expect the boost converter to consume no more than 1A from either the battery or the 5v USB supply. Q4 is there to disconnect the output of the module when 5V is present from the USB port. I am using BAT48 diodes in parallel to block current from the battery back to the USB port and R8 is used to lower the voltage at the gate of Q4 due to small leakage currents from D3-D6.
Is there any any obvious problems with this adaptation and how should i determine the value of C5 to ensure that it switches between USB/Battery when the USB cable is plugged/unplugged?