Best Li-ion Battery Setup for 7" Cinematic FPV – Need Advice

General
1

Hello everyone,

I’ve built a 7" FPV drone with the following configuration:

  1. Frame: iFlight XL7 V5 (7 inch)
  2. Motors: Flywoo NIN v2 2806.5 1350KV
  3. Flight Controller: Matek H743-SLIM
  4. ESC: T-Motor P50A 3-6S BLHeli_32 4-in-1
  5. Propellers: Gemfan Cinelifter 7035 (7×3.5×3 Tri-Blade)

The dry weight (without battery) is 530 grams.

My goal is to achieve long flight times for cinematic flying only—I don’t do freestyle or acrobatics.
I’m using Molicel INR21700 P42A Li-ion cells and would like advice on which battery configuration to build.

Here are the options I’m considering:

  1. 6S2P – 8400mAh, weighs ~900g
    2.Concern:* Heavier weight, though offers higher capacity.
  2. 6S1P – 4200mAh, weighs ~450g
    4.Concern:* Lower capacity, but lightweight.
  3. 4S2P – 8400mAh, weighs ~600g
    6.Concern:* Lower voltage (4S), may impact efficiency or thrust.

Question:
Which battery configuration would you recommend for smooth and extended flight time on this 7" setup?

2

Im using 4S2P setup on 560mm quad carring gimbal with 13 inch props and i can say i like it, i get over 30 mins of flight time on it. Not sure about your motors how they are efficent on 4s vs 6s. But for sure weight between 4s and 6s is big so for cine crusing i guess you will get better flight time with 4s.

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3

ecalc

Keep in mind the battery weight in ecalc is per-cell until you see the total down in the summary.

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4

Thank you all for your valuable time.
Upon further research, I found that my motors — Flywoo NIN V2 2806.5 1350KV — are most efficient when used with a 6S setup. Additionally, since lithium-ion cells perform better with lower current draw, using a higher voltage (6S) system helps reduce the current. Therefore, I should go with either a 6S1P or 6S2P configuration. However, since the 2P setup will be heavier, the 6S1P option seems more suitable.

5

I would go with the 6S1P setup. The 6S2P would give you more flight time - but probably only 35% more flight time for a 100% increase in battery capacity.

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6

i am thinking same way

7

I use 6s2p for my 8" drone, but this is almost 2kg total mass. It can fly over 30 minutes, but I am considering switching to 1p - probably not much shorter flight time but much lighter and agile drone.

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8

Than you all for valuable inputs, I decided to go with 6S1P

9

Great! Let us know how it goes!

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10

I like these cells better, more capacity and high discharge rate.

11

Right now I use Molicel P45B and they are very good. I would also look on EVE 50PL.

12

The Molicel 42A, 45B, and 50B are all great cells! Just depends what your budget is (42A is cheapest, 50B is most expensive).