Electronics/Safety of wiring aa batteries in parallel
I made an external psu for a flash gun.
It is working well, I used 2 dummy batteries to make the connections inside the flash gun battery compartment.
In the external enclosure I have 4 xx AA battery holders wired in parallel to give a 6v supply with a much higher aAh than just one set of 4xAAs.
Each of the 4 battery holders inside the enclosure contains 4 x aa batteries connected in series to give 6v.
I would like to know what, if any are the potential dangers of this system?
I have a switch in the enclosure that cuts off the combined 6v supply to the flash but the 4 battery holders are still permanently connected in parallel
Do I need to install more switches so that when the unit is not in use, then the parallel connections between the 4 battery holders are disconnected?
The picture shows the kind of 4xAA battery holder that I have connected in parallel.
I think you will be alright.
You should use all the same make of battery from the same pack (I use the 4 unit pack from Dollar Tree) for example.
When the unit is OFF there is no current being drawn and even when they are low in charge the voltage is pretty near full level so the battery packs will not 'feed' each other.
If one or more of the batteries is much more 'used' than the rest it can give an imbalance in the voltage and cause some imbalance. But, if when changing batteries they are all the same, new units they will discharge at the same rates and you will have good results all the way through until a new set is required.
That is my opinion. Let me know if you need more.
PS: Have you thought of using a single 6v battery? There are many sizes and strengths to choose from.