A way of connecting batteries together to provide more current is to connect them in parallel. This allows more capacity at the same voltage. If the batteries were connected in series the voltage would be increased.
If each battery is identical, yes.
12 volts only refers to the voltage, to be able to say anything about charge time you also need to know the capacity rating in amp hours of the batteries. Assuming lead-acid batteries the charger needs to go to > 14.4 V and then a proportional amount of amps as compared to the capacity rating of the batteries. A rough approximation is that batteries needs to be charged with about 1.4 times their amp rating. An 1 Ah battery would need 2 hours on a 0.7 amp charger for instance.
A == B (- 12V +) (- 12V +) (- 12V +) A single 12V battery in series with 4x 12V batteries connected in parallel... Total voltage from A to B is 24 volts! Note that the single battery in series will limit the total current capacity to that of a single battery.
A Darlington pair is two transistors connected together to give a very high current gain.
Batteries provide Direct Current (DC) while household outlets provide Alternating Current (AC).
If each battery is identical, yes.
If you connect 2 six volt batteries in parallel it will still give you six volts but it will give you twice the cranking power. To obtain twelve volts from the two six volt batteries they will have to be connected in series.
The number of batteries has only an effect on the amount of current when they are equivalent and connected in parallel. The amount of current that can flow from a group of batteries connected in series is limited to the current provided by the battery that produces the lowest current flow in the string.
You get more voltage and current capacity.
Two batteries can supply more current than one if they are connected in parallel.
Electrical Current
It depends how they are connected. If the terminals of two 12 volt batteries batteries are connected to the same circuit (in parallel) then there is no change in the flow of current- it will just last for twice as long a time. But if two opposing terminals of the batteries are connected to each other first and the free terminals then connected to the circuit (in series) then there would be a total voltage of 24 volts and twice as much current would flow. The two batteries would last for the same length of time as one battery on its own.
12 volts only refers to the voltage, to be able to say anything about charge time you also need to know the capacity rating in amp hours of the batteries. Assuming lead-acid batteries the charger needs to go to > 14.4 V and then a proportional amount of amps as compared to the capacity rating of the batteries. A rough approximation is that batteries needs to be charged with about 1.4 times their amp rating. An 1 Ah battery would need 2 hours on a 0.7 amp charger for instance.
Yes, series and parallel connection of batteries is possible. When connected in series Voltage increases. In parallel, Current increases but voltage is constant.
Two batteries, put them in series and either measure the voltage with a voltmeter, or with a fan connected watch the speed increase. A parallel connection will increase the current available but will not have an obvious change in output, as the current available is just that, ready for use. You can do something else with parallel and that is to have a volt meter showing that there is a current flow between the two batteries and that is why batteries connected in parallel will discharge.
"dc" is direct current which is what batteries use, whereas "ac" is alternating current, which is what your household receptacle uses.
That will depend on the sum of the load resistance and the internal resistance of the battery (this is true for all power sources, not just 6 volt batteries). Small compact batteries tend to have higher internal resistance and therefore are more limited in the current they can deliver to a given load than larger batteries.