What voltage are you talking about?
If you are talking about the dash volt guage, the batt temp sensor would have no effect on that.
The only way to read batt temp and sensor voltage is through a scan tool.
Really a non- issue as I see it, as long as the guage is 'close', then good enough. a different [new] battery can have an effect on how the system reads, and how much it charges. there is most likely less of a load on the alternator so the guage doesn't read as high as it did before.