There are many ways to power FPV Goggles for longer battery life. In this article I will show you the different ways and batteries and explain the pro’s and con’s.
The power options described in this tutorial should be suitable for many FPV Goggles out there, including Fatshark, Eachine, Aomway and Skyzone. As long as they take 2S voltage, and use a 5.5mm 2.1mm barrel connector.
Further Reading: How to choose FPV Goggles
Battery life can be estimated by dividing the capacity by the current draw of your FPV Goggles. For example, the Fatshark Dominator V2 using True-D diversity module consumes around 0.5A, an 2S 1000mAh battery will roughly last 2 hours.
Dedicated 2S LiPo battery
Many FPV Goggles commonly provides 2S LiPo batteries of capacity between 1000mAh to 1800mAh. For example, the Dominator V3 comes with a 2S 1800mAh battery, which should last about 3 and a half hours approximately (with a diversity receiver module).
If you are looking for longer battery life, you can get batteries with larger capacity such as the Tattu 2S 2500mAh. This battery is designed specifically for FPV goggles and comes with a 5.5mm barrel connector.
So far this is my favorite option, I get nearly 5 hours out of it!
This 2000mAh 2S from Banggood is a really cheap option. It’s actually designed for the Taranis QX7 TX and doesn’t have a barrel connector, but you can still use it for your FPV goggles by making a battery adapter.
18650 Li-Ion Batteries
From my 18650 batteries test, I had good result from Panasonic NCR18650B 3400mAh. These give me a total of 4 hours and 20 minutes battery life on my goggles.
The idea is to connect two of these cells in series to make a 2S pack. 18650 batteries are becoming a popular option to power FPV Goggles due to its high capacity per gram and low cost.
However there are some downsides to 18650 batteries…
First of all, you are NOT getting the advertised capacity. You can’t charge and discharge 18650 batteries to its maximum and minimum voltages (well, you are not recommended to). So you will probably be only using 2/3 of its capacity realistically. For example, for a 3400mAh cell, the effective capacity might only be about 2200mAh.
Another annoying thing is the low voltage alarms will start beeping early in the second half of the battery. Most FPV goggles are designed to be used with LiPo and some of them have a voltage alarm at about 3.6V to avoid over-discharging. However the 18650 batteries can be safely discharged to much lower voltage, i.e. 3.1V.
Some other minor negatives with 18650 batteries:
- They take longer to charge because you can only charge them with 0.5C or lower
- They require a dedicated charger, or a good LiPo charger that supports Li-Ion batteries
That’s why I still prefer using my 2S 2500mAh LiPo…
Fatshark 18650 Cell Case
If you are looking for a ready-made case for your 18650 cells, Fatshark made a really handy case for that. It comes with a 4-level battery voltage indicator, and is shaped to fit perfectly in the Fatshark Goggles head strap.
However it’s pretty bulky and it’s not meant to be used for charging the cells. The balance lead is missing a middle wire so it cannot be used for balance charging. It’s recommended to take the cells out, and use a dedicated 18650 battery charger to charge them.
Using a 2-cell 18650 battery holder, and some connectors of your choice, you can easily make your own an case. It’s cheaper, more flexible and functional.
The 2S balance lead allows you to balance charge the battery. The voltage indicator is optional, it will allow you to easily check the battery voltage and help prevent over-discharging.
- 2-cell 18650 battery holder: Amazon | Banggood (get the one shown in the picture below)
- 5.5mm Barrel for FPV Goggles: Amazon | Banggood | GetFPV
- 2S Balance Lead: Amazon | Banggood
- 2S Voltage Indicator: Banggood
To overcome the “early voltage alarm beeping” problem caused by the wider working voltage in 18650 cells, some people use a step up voltage regulator to increase the output voltage to 9V.
It’s a clever workaround, but it’s not perfect. The downside is that you can no longer charge your battery with the discharge lead anymore, so we don’t really recommend doing it.
You can get a step down voltage regulator to convert higher voltages down to your Goggle’s voltage input level. This is extremely flexible as you will be able to use larger packs such as 3S, 4S… even 6S as long as your regulator supports it.
I might do a tutorial in the future.