Hi!

I am studying about lithium polymer batteries.

I have trying to find a concrete answer to my problem mentioned below.

The question is - Which will give a better performance - Using a single large capacity battery (say 11000 mAh) or using multiple small batteries in parallel (say five 2200 mAh) to give equivalent capacity to the large battery? We are drawing equal current in both the cases.

All the information and help would be highly appreciated. It would be great if you could support your points with credible references

Lipo batteries are split into cells (even if the pack is one big pack) of 3.7v nominal (4.2 - 4.3v fully charged) therefore a mavic pack for example is 3s (3x3.7v nominal). So to be honest it really depends on the total voltage you need to supply, what the continuous and peak current draw will be followed by the required duration at that continuous current. Then you can calculate how many cells you need as well as the capacity. However that all said and done 2 of one type of battery wired in parallel will always be able to provide more current than the same type of battery by itself. But you need to consider other things before coming to a firm conclusion over what your particular requirement is.

Hey Dan!
Thanks for your reply.

Let me make my question a little more easy (I hope!).
Which will provide more nominal energy - single 11000 mAh battery or 5 2200 mAh battery connected in parallel?
Currently, voltage is not a concern. If you can explain in terms of nominal energy, energy density, power density etc., it would be great.

Most likely the 5x2200mAh, but it depends on whether you want all that 11Amps provided over an hour or whether you'd prefer 66Amps in 10 minutes.

If you look at the LiPo batteries for sale, you'll see them advertise a "C" rating for discharge and possibly another "C" rating for charging.  Those have to do with how fast the battery can provide current and how fast it can be charged.  Some batteries just can't pump out current as fast as others.  They all should be able to provide the label rating, say 11,000mAh over the course of the hour, but the "C" rating will determine if they can provide that same energy in shorter bursts.  Batteries that can't will exhibit a large drop in voltage which ESCs will take as meaning that the battery is depleted.  Also batteries may overheat or puff if they are discharged faster than rated.

Here's an example you can Google to see the ratings:  Turnigy nano-tech 3000mah 4S 25~50C Lipo Pack
Capacity: 3000mAh
Voltage: 4S1P / 4 Cell / 14.8V
Discharge: 25C Constant / 50C Burst
Weight: 299g (including wire, plug & case)
Dimensions: 150x45x24mm


(Of course, the wires used to connect the battery to the device drawing the current also need to be able to handle the current and heat).

nicely done - thanks for sharing.