Hi
here how to connect the TP4056
TP4056
I use only modules with battery discharge protection(3 ic s on the pcb, not those with only one)
and here how is the datasheet schematic for the capacitors. I put ceramic caps and 1000uA electrolyts but you can try with other combinations.
HT7333
Then i soldered a on/off switch because often the mkrfox hang up booting with empty caps.
If you read in the FAQ of the mkrfox1200:
Q: Can I attach a Li-Po Battery to the board?
A: No, the board is designed to run with a 3V battery pack. A battery pack is made up of 2 AA or AAA batteries in series. No more tahn 3V must be applied otherwise the board will be damaged.
Powering the Arduino without solar panel maybe i will find another solution, like rechargable ni-mh, but with panel i dont think the LDO will make problems.
lifepo4 is another solution, but i dint find a cheap charging module.