Problems with the ADS1115 A to D converter

For now I think I’ll be ok with the setup I have.
I may change to 1w metal foil resistors when they come the reading difference between a low and high voltage battery is 0.1v but various connections not solder points may be the cause of that I have enough ADS115 boards free and resistors I’ll build up a prototype with all solder connections.
Kendrick