# Does battery capacity double in parallel?

Hi,

I have three 1.5v batteries (14 Ah) connected in series. So the total voltage is 4.5v and the capacity stays at 14 Ah.

Now if I get another set of the same batteries and connect them in parallel to the first ones, does the voltage stay at 4.5v and the capacity increase to 29 Ah?

Thanks

Yes.

If the batteries are in parallel the voltage will be 1.5 volts. Times 14 amps x 3 = 63 watts, in series, 4.5 volts, times 14 amps = 63 watts.

Well, 28 actually, providing the chemistry of all batteries are the same.

outsider:
If the batteries are in parallel the voltage will be 1.5 volts. Times 14 amps x 3 = 63 watts, in series, 4.5 volts, times 14 amps = 63 watts.

But your scenario is different that what is being discussed in this thread.

And you confused some of the terminology.
We are discussing AH = Ampere-Hours.
You are discussing Amps.
You have assumed that "Amps" and "AH" are the same thing.
They not the same thing.

You did not take the time to actually read the OP's question ...
"Now if I get another set of the same batteries and connect them in parallel to the first ones,
does the voltage stay at 4.5v and the capacity increase to 29 Ah?"

The answer to the OP's question is: Yes, the capacity is double
because the OP has now paralleled two sets of 3-Batteries-in-series each = 6 batteries total.

Do you now understand why the capacity has doubled?

Caveat: Do not mix old and new batteries. Not in series, not in parallel. In series, the current through all of them must be the same - so the half-dead battery will be dead when the other batteries are only half dead - and depending how many batteries are in series, they may keep forcing current through the dead battery, which can lead to leaking batteries. In parallel, it's even worse, because the new battery will attempt to charge the half-dead battery; this will not do favors for either participant, and may result in the batteries getting hot.

DrAzzy:
Caveat: Do not mix old and new batteries. Not in series, not in parallel. In series, the current through all of them must be the same - so the half-dead battery will be dead when the other batteries are only half dead - and depending how many batteries are in series, they may keep forcing current through the dead battery, which can lead to leaking batteries. In parallel, it's even worse, because the new battery will attempt to charge the half-dead battery; this will not do favors for either participant, and may result in the batteries getting hot.

On top of that (for mixed batteries), If we're talking about rechargeable batteries in serie there is a risk that they won't charge at the same rate and one of them can be overcharged (damaged) compared to an other.

Supertesla:
On top of that (for mixed batteries), If we're talking about rechargeable batteries in serie there is a risk that they won't charge at the same rate and one of them can be overcharged (damaged) compared to an other.

From the description, 1.5 Volt 14 AH Battery,
I am guessing the OP is talking about a Non-Rechargeable Long-Life Alkaline D Cell.

mrsummitville:
From the description, 1.5 Volt 14 AH Battery,
I am guessing the OP is talking about a Non-Rechargeable Long-Life Alkaline D Cell.

You're right otherwise it is 1.2V, my bad. Please forget my previous message then