Yes, two or more batteries connected in series can generate a higher voltage than one alone.
The cells are the individual units that provide voltage. In a battery, several of them are connected in series, to provide a higher voltage.
no..... The battery with lower voltage will consume power from the higher one...
Batteries in parallel maintain constant voltage across the load rather in a series, so it is better to arrange the batteries in parallel Batteries in series deliver a higher voltage, batteries in parallel have longer life use.
If two ideal sources of unequal voltage are connected in parallel the higher voltage will provide a majority of the current (a two percent difference in voltage would provide an additional 5% of the current) and (in the case of batteries) the larger would provide charging current, quickly draining it.
cells must be connected in series
If you apply a higher voltage to a capacitor than it is rated it could over heat and explode.
Putting batteries in series will up the voltage of the entire circuit. Certain things need higher voltage, so you put your batteries in series. Putting batteries in parallel will not up the voltage, but will let the current last longer. Watches would be more of an example for that. You want watch batteries to last long.
To charge a battery, the charger voltage must be higher than the battery voltage. If a AA battery (or any other) has a normal voltage of 1.2V the charger voltage must be at least 1.2V. The type of voltage supply and its current capability is immaterial. No, the charging voltage have to be larger than the battery voltage, to charge 2 AA batteries, that is 3 volt if connected in series, so a voltage of at least 4 volt is needed
Four 9v batteries connected in a parallel will still emit 9 volts because you are not increasing the voltage, you are increasing the life. To increase the voltage of four 9v batteries, you must connect them in a series; that series will emit 9v X 4(batteries), which equals 36 volts.
Stereo can't work unless sufficient voltage , same will be connected to higher input voltage your system will be damaged.
There is no answer to this question. It could be anywhere between 2.5V and 12V. If you connected them in series the answer would be 20.5V, in parallel the higher voltage battery will discharge into the lower rated cells, the resultant voltage is dependent upon the internal resistance of each of the batteries. In practice you wouldn't do this, so it's either a mistake or trick question. www.powerinspired.co.uk
You equalize deep cycle batteries by charging with a higher than normal voltage for a short period of time. Consult the manufacturer for details.