[Solved] Have the Wemos and BME been damaged? ESP8266 battery power supply.

I need to make a temperature, humidity and pressure control module, i.e. BME280, and to this a soil moisture control with an analogue capacitive sensor. All powered by a solar panel + 18650 battery.
At the moment I have run the power supply from the 18650 battery via a TP4056 charger module and because the soil moisture sensor needs 5V on the power supply a MT3608 step-up inverter is connected to the charger output with the output voltage regulated and set to 5V,
Wemos powered from the 5V inverter, BME powered from the 3V3 pin of the Wemos, Solar panel and soil moisture sensor I haven't hooked up yet.
I put this together on a prototype board with goldpins soldered on so that the Wemos could be easily replaced if necessary, plus connectors for the sensors.
Everything worked fine on the phone's USB-C power supply (interestingly, the TP4056 does not work on an apple.... power supply, but on a samsung one), and the battery was charged.
The chip ran on the battery for more than 24hrs after which it shut down.
And now the trouble started. I measured the voltage on the battery and saw 1.6V - does this mean I have a blown TP4056? Because I guess it should disconnect the output at around 2.5V?
But the second problem is more serious...the wemos doesn't connect to the wifi when I plug the power either into the TP4056, or when I unplug the whole power circuit from the battery and plug the USB power directly into the Wemos. There is no connection and that's it, only the LED flashes.
It also doesn't get up when plugged into the USB on the computer.... only that it is woken up by the initiation of a serial transmission via USB.... When the connection is initiated by the putty, the wemos boots up, connects to the wifi, but the reading from the BME doesn't work.
Interestingly after removing the wemos from the board it gets up without a problem whether on usb power supply or from the computer.
There is nothing on the board.... connectors for the goldpins, connector for the power supply circuit, and connector for plugging in the BME + wires connecting D1,D2, 3V3 and GND to the connector for the BME.... Checked with a meter and everything seems ok, no short circuits.

I wonder what could have happened.... did it damage the wemos? BME as well? Could it be that the inverter as its input voltage drops below 2V is able to give more than 5V to the output and damage the circuits? But the BME is powered from 3.3V and not from the inverter....

I'm wondering what to do next, as the circuit is quite typical and I wouldn't want to possibly screw up another wemos or BME....

Krawietz

TP4056 has no over-discharge protection. If you have a board with an extra DW01 chip and mosfets then you might want to check for a puncture between the drain and source - either something is fouled or you have wired something wrong (which is also likely ). Also try to work out if that one sensor happens to go to 3.3V - sometimes there are no problems, sometimes you just need to change the resistor.... Generally the esp8266 doesn't like Chinese inverters - a friend has already been run over once.

In theory, the plate should be with safety features:
O such.
.

The sensor might go on 3.3V you have to check experimentally because it is a waterproof version.
And as for powering without an inverter, I see on the web that people plug the charger output directly into the 5V input of the wemos. The question is how much capacity can be removed from the battery before the voltage drops enough for the wemos' internal power supply to say enough.

The wiring is all rather correct.... Aku is B+ and B-, output to inverter input and output from inverter to GND and 5V to wemos.

I'll have to check for starters what's wrong with the wemos, that it's having freaks when booting and can't see the BME. Unless the inverter has somehow rammed it.... And I hope that the BME itself is not dead, because it costs a few zloty more than the rest of this crap....

Kraiwetz

BME works...
The wemos also works rather well....
I removed this inverter from the Wemos power circuit and connected the battery charging module output directly to the 5V of the wemos.
It starts and works stably. The soil moisture sensor in the original specification has a supply range of 3.3 - 5V.
However, the battery charging module broke down.... specifically, the circuit responsible for disconnecting the power supply has broken down - I don't know what happened to it but it looks 'cooked'.

Krawietz