Hi all,
Quick question: if I can connect two identical and balanced batteries to my Y6 in parallel using an XT60 Y-connector, could I connect four identical and balanced batteries in parallel using 3 Y-connectors?
Let's assume I have the lift capacity for four batteries for now.
I'm totally prepared to be told that that's a ridiculous question, but I haven't been able to find anything to say I can't. Nor have I found anything that says I can. :)
Thoughts?
Replies
You can attach as many batteries connected in parallel as you can lift. You just have to calculate the max Lift of your quad and then see how much batteries you can plug in parallel. I recomend you looking for high mAh rated batteries.
David Rodriguez
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owner of http://www.multirotorguides.com
Multirotor fanatic
You can attach as many batteries connected in parallel as you can lift. You just have to calculate the max Lift of your quad and then see how much batteries you can plug in parallel. I recomend you looking for high mAh rated batteries.
David Rodriguez
________________
owner of http://www.multirotorguides.com
Multirotor fanatic
Take a look at eCalc
You will find answers regarding the number/capacity of Lipos vs. flying time.
Important is Lipo to be the same capacity.
After more searching, I fount this comment, with some good stuff on the thread about battery life in general:
http://diydrones.com/xn/detail/705844:Comment:1408534
This link is also helpful on battery efficiency in terms of 3s vs 4s:
http://diydrones.com/xn/detail/705844:Comment:1431880
Thanks, James! There's always a catch. ;)
You've got some large batteries there. I've been evaluating batteries in terms of their mah/g ratio, and it seems as the batteries get larger that ratio goes down. E.g. my 3s 3300mah Kypoms are 263g, about 12.5mah/g, whereas a number of larger (6000mah, 8000mah) 3s batteries have ratios more like 10 (and also cost a little more).
Can one get more flight time by using a large number of smaller batteries, or is there a catch with this too beyond the assymetric battery drain due to differing impedance between batteries? For example, perhaps there is some roughly constant number of mah you can't get out of any battery, making a bigger dent in the usable mah in a smaller battery.
Nick
Hi nickthecook,
Not a ridiculous question at all. Within the lift capacity of your copter, there is nothing stopping you from doing this, however because the increased weight and the reduced efficiency of increased prop loading, there are diminishing returns. Doubling your battery capacity does NOT double your flight time. In addition, there are some issues with matching battery impedance when connecting packs in parallel. Within a given pack, cells are carefully matched, but between packs there can be significant differences. The pack with the highest impedance will have the highest voltage drop so will shoulder proportionally less of the load. I use 2 x 4S 8000mah packs in parallel. I have one particular 4S pack that will consistently only discharge by 2500mah when in parallel with other my packs that will discharge by around 6000mah