$$\ce{Cu^2+ + Ni -> Cu + Ni^2+}$$
The standard potential of this redox reaction is 0.57 volts (which was obtained by 0.23 + 0.34)
$$E = E_0 - \frac{RT}{nF}\ln Q$$
I used 0.1 M nickel sulphate and 0.5 M copper sulphate in my galvanic cell.
$$E_{25} = 0.57 - \frac{8.31 \cdot 298}{2 \cdot 96485}\ln(0.2)=0.59065\ldots$$
$$E_{45} = 0.57 - \frac{8.31 \cdot 318}{2 \cdot 96485}\ln(0.2)=0.59204\ldots$$
Shouldn't the two be inversely proportional? Is the effect of temperature really this minuscule?