Which Is More Efficient: 4S or 6S Batteries For FPV?

As the popularity of First Person View (FPV) drone flying continues to soar, enthusiasts are always seeking ways to maximize flight performance and duration. One crucial factor that affects flight efficiency is the type of battery used. In this blog, we will delve into the comparison between 4S and 6S batteries and determine which one is more efficient for FPV applications.

First of all, let's check how Joshua Bardwell said about this qustion below:

"6s or 4s cost for flight time. that's very hard to say.there are so many variables
Ryan Harrel who is one of the smartest guys I know, when it comes to motors, props and ESCs,among other things but certainly that in that area he is one of the premier people in FPV. He's done a ton of bench testing of motors and ESCs, he understands motors and ESCs at a level that very few people in FPV do, not just from a theoretical perspective, but from a practical lab bench testing and flight testing perspective. so Ryan Harrel argues that 6s is actually less efficient, now I wish I had a copy-paste of the argument he makes so I could show it to you because I am not going to try to do it justice people say that 6s is more efficient for various reasons he says it's not his arguments sound convincing his credentials are impeccable and I tend to believe him. so why do people tend to get longer or at least seem to get longer flight times when they go to 6s. I think subjectively when I switched from 4s to 6s, it felt like I noticed the battery sag
later in the pack, with 4S I would start to feel the battery sag I would go oh I need to stop flying and I would come land, and, when I switched to success I just killed pack after pack because I didn't feel that sag and if I wasn't watching the OSD to see the battery get down to 3.5, 3.4, 3.3 then I would just flat and kill it. I don't kill packs anymore, but I will regularly fly a 6s pack down to 3.5 and still have plenty of life in it, and people could be like oh I need a land whereas I just don't remember that happening on 4s packs. One reason that might explain this is that when people go to 6s packs, they tend to go to a little bit larger pack, so people will fly an 11 million hour or 12 million hour 6s battery weighing two hundred and five grams, when they used to fly a 13 million hour 4s battery, weighing 175 or 180 grams, you simply have more battery, so in a lot of cases, the differences people notice between 4s and 6s can be attributed to the fact that they're not really doing apples to apples comparison, the other change that people tend to make is they tend to run higher KV motors on 6s than the equivalent 4s, so they're essentially getting more RPM and more thrust, now you would think that would make the quad have shorter flight time, but who knows. The answer is that on paper 4s will give you more efficiency, more grams per watt, but most people are going to fly 6s and feel they get better performance from it."

Before you make any choice, you need to understanding the Basics first:

Before diving into the comparison, let's briefly explain the differences between 4S and 6S batteries. The "S" stands for "cells in series," representing the number of lithium-ion cells connected consecutively to form a battery pack. A 4S battery consists of four cells, while a 6S battery has six cells.

Comparing Voltage:

Voltage is a significant consideration when deciding between 4S and 6S batteries. Each cell in a LiPo battery has a nominal voltage of around 3.7 volts. Therefore, a fully charged 4S battery will have a maximum voltage of 14.8 volts (4 cells x 3.7 volts), while a 6S battery will reach 22.2 volts (6 cells x 3.7 volts). The higher voltage of a 6S battery provides increased power output and potentially higher efficiency.

Flight Performance and Thrust:

Higher voltage directly translates to increased motor RPM, resulting in more thrust and better flight performance. With a 6S battery, the motor spins faster, allowing your FPV drone to attain higher speeds and maneuver more quickly. Additionally, the higher power output of a 6S battery means the drone can carry heavier payloads, such as cameras or additional equipment, without sacrificing flight stability.

Battery Efficiency and Flight Time:

When it comes to battery efficiency and flight time, multiple factors come into play. While 6S batteries offer higher voltage and more power, they also tend to be heavier due to the increased number of cells. The additional weight could potentially reduce flight time compared to a lighter 4S battery. However, the overall efficiency depends on the specific setup, flight style, and components used in an FPV drone.

Safety Considerations:

It's important to note that higher voltage batteries, such as 6S, require compatible components and careful consideration of safety measures. These batteries deliver more power, which can strain the electronic speed controllers (ESCs) and motors, leading to increased heat generation and the risk of damage if not managed properly. Always ensure that your drone is equipped with components rated for the voltage you intend to use and monitor the temperature during flight.

Conclusion:
In the debate between 4S and 6S batteries for FPV applications, there is no definitive answer as to which is more efficient. It ultimately depends on your specific requirements, flight style, and drone setup. While 6S batteries offer higher voltage, increased power, and better flight performance, they might also have reduced flight time due to their higher weight.

If you prioritize longer flight duration, especially for endurance-focused FPV flights, a CNHL 4s Lipo Battery might be a better choice. On the other hand, if you prioritize agility, speed, and the ability to carry heavier payloads, a CNHL 6Ss lipo battery would be more suitable.

Ultimately, it's essential to consider your specific application, budget, and the recommendations of experienced FPV pilots. Evaluating the pros and cons of each battery type will help you make an informed decision that aligns with your individual needs, maximizing the overall efficiency of your FPV drone.