power esp32 from battery(li ion 18650) with a temp sensor

[bernardthedog]

hi
i have an issue with powerering an esp32 from battery 18650, and also a temp sensor that i draw power from one of the ports on the esp32.
the temp sensor draw 3.3v.
When i i have this setup connected to usb it works great, but when i use the battery there is not enough power. and is obvious something basic that i'm missing here..
when i connect from battery to the esp and remove the sensor it seems to be working.

is it not enough voltage i have from the battery, or amperage?
and if its volt, how would i handle it?
and if i add more voltage to this setup and if i turn off the port to the sensor, then i would get to much voltage to the esp and it will die right?

im not sure how to proceed with this ?

[bidrohini]

Hi, which particular temperature sensor are you using?

[bernardthedog]

its this: https://www.adafruit.com/product/1893 , MPL3115A2.

it seems like my issue is with homespan first of all, when i use usb its working perfectly with both homespan and also mpl3115a2. But not working with i use battery, and not working with (power lab station).

also another issue when i use a voltometer, the output pin outputs 3.2xxx volt, not 3.3 stable. shouldnt it delivery 3.3v ?

[bidrohini]

Is your battery fully charged? I mean, did you measure the battery voltage immediately after charging(without connecting to your circuit)? Does it read 3.7V?