Oh ok not he battery is fine nev no build up it’s just as the increased rpm the voltage to the battery and then in turn to the instruments also increases to a point where it’s sometimes around 18 volts now in my limited understanding I’d believe that the voltage regulator should limit to about 14.5 v max and increase the current for an increase in rpm while holding a steady voltage to a point where the battery is charged and then floats the current?