Lithium-ion (Li-ion) batteries stand out for their impressive energy density, offering longer flight times compared to traditional LiPo batteries. The Lumenier NAV Li-ion Battery series is specifically designed for long-range FPV pilots who crave extended flight time. These batteries excel in lower amp draw drones and planes, and they’re also perfectly suited for FPV gear like radios and goggles.
Looking for a battery charger? Check out my charger buyer’s guide: https://oscarliang.com/choose-lipo-battery-charger-power-supply/
Table of Contents
Where to Buy?
Get your Lumenier NAV battery from GetFPV
- 6S 3000mAh: https://oscarliang.com/product-0j2q
- 6S 6000mAh: https://oscarliang.com/product-h4hg
Lumenier offers two versions with different capacities: the 6S 3000mAh and the 6S 6000mAh. Both use the same li-ion cells but differ in cell configurations; the 6S 3000mAh features a 6S1P arrangement, while the 6S 6000mAh utilizes a 6S2P setup.
Why Using Li-ion over LiPo?
In my Li-ion battery buyer’s guide, I delve into the advantages and drawbacks of Li-ion batteries in comparison to LiPo https://oscarliang.com/li-ion-battery-long-range/
While LiPo batteries excel in delivering high burst power, making them optimal for racing and acrobatics, Li-ion batteries has higher capacity per weight. The choice between the two battery types in the FPV drone world depends on the specific goals of the pilot, with Li-ion batteries offering advantage in endurance.
Despite being only slightly larger, a Li-ion battery can offer triple the capacity of a LiPo as you can see in this size comparison between a 6S 1050mAh LiPo, 6S 3000mAh Li-ion and 6S 6000mAh Li-ion battery.
6S 1000mah LiPo; 6S 3000mah Li-ion; 6S 6000mah Li-ion
Specifications
6S 3000mah:
- Cell Type: Li-ion 18650
- Cell Configuration: 6S1P
- Nominal Voltage: 22.2V (3.7V per cell)
- Max Voltage (Fully Charged): 25.2V (4.2V per cell)
- Discharge Cut-off Voltage (min voltage): 2.5V per cell
- Rated Capacity: 3000mAh
- Discharge Rate: 10C
- Continuous Discharge Current: 30A
- Burst Discharge Current: 50A
- Rated Charging Current: 1.5A (0.5C)
- Maximum Charge Current: 4.5A (1.5C)
- Battery Plug: XT60
- Typical Internal Resistance: 13mΩ (per cell)
- Watt-hour: 66.6WH
- Dimensions: 70x55x38mm
- Weight: 314g per 6S Pack, 45g per cell
6S 6000mah:
- Cell Type: Li-ion 18650
- Cell Configuration: 6S2P
- Nominal Voltage: 22.2V (3.7V per cell)
- Max Voltage (Fully Charged): 25.2V (4.2V per cell)
- Discharge Cut-off Voltage (min voltage): 2.5V per cell
- Rated Capacity: 6000mah
- Discharge Rate: 10C
- Continuous Discharge Current: 60A
- Burst Discharge Current: 100A
- Cell Rated Charging Current: 1.5A
- Cell Maximum Charge Current: 4.5A
- Battery Plug: XT60
- Typical Internal Resistance: 13mΩ (per cell)
- Watt-hour: 133.2WH
- Dimensions: 135x55x47mm
- Weight: 637g per 6S Pack, 45g per cell
Bench Testing
Capacity
To assess the true capacity of the Lumenier NAV 6S 3000mAh and 6000mAh batteries, I conducted a discharge test down to 2.7V per cell with a discharge current of 2A (0.5C). This current level is low enough to prevent the battery from warming up and consequently wasting energy.
For the Lumenier NAV 6S 3000mAh battery, the measured capacity was approximately 2880mAh.
6S 3000mAh
Given that the 6000mAh version uses the same type of cells as the 3000mAh one, I expected its capacity to be roughly double. The assumption was proved accurate as it measured around 5763mAh.
6S 6000mAh
Discharging
I compared the performance of these Lumenier NAV 18650 cells with the popular Molicel P28A 18650.
The Molicel P28A has a specified maximum discharge current of 35A (according to its datasheet), while the Lumenier claims 50A (based on the product page), a bold assertion indeed – it would be interesting to see if this claim holds up.
From the graph below, the Molicel exhibited noticeable better performance, showing about 0.4V less voltage sag through most of the discharge cycle. However, its voltage dropped sharply towards the end, suggesting it might have a higher cut-off voltage than the Lumenier. Therefore, to be on the safe side, I wouldn’t discharge the Molicel P28A below 3V per cell. On the contrary, the Lumenier’s voltage decreased relatively linearly down to 2.7V.
Internal Resistance
The Lumenier NAV’s internal resistance (IR) appears to be around 13-15mΩ, aligning with the specifications. But they are a bit higher than the Molicel P28A’s 10mΩ. Note that these measurements were taken on my LiPo charger. While LiPo chargers might not offer the most accurate IR, they provide a useful benchmark for comparison between batteries.
Building Your Own Li-ion Packs
Building your own Li-Ion battery is also an option, I will show you how to do it using my own method in this post: https://oscarliang.com/li-ion-battery-long-range/
My go-to 18650 cells have been the Molicel P30B and P28A, popular for long-range aircraft due to their performance, offering up to 35A of discharge current. You can see my testing of these cells here: https://oscarliang.com/best-18650-li-ion-battery/
While building your own can be rewarding, it’s worth noting that it often costs as much as purchasing a pre-made battery. More importantly, building a battery pack can be hazardous and time-consuming if not executed correctly. If there’s any doubt or concern, I recommend opting for an off-the-shelf product for safety and peace of mind.
Conclusion
I noticed that the wires on these batteries seem somewhat excessive. Opting for thinner wires could have shaved off a few grams without sacrificing performance.
From the tests conducted, it appears that the cells used in the Lumenier NAV Li-Ion packs exhibit lower performance compared to the Molicel P28A in terms of burst current.
I personally use P28A a lot and it’s relatively affordable, costing less than £7 in the UK (around US$8-$9), so building a 6S pack would only cost US$50, making it a cheaper option. However, opting for the Lumenier NAV eliminates the trouble and risk you have to go through making your own battery, which is a significant advantage. Although they might not deliver top-tier performance, these batteries are sufficiently competent for long-range aircraft with low amp draw requirements.
Get your Lumenier NAV battery from GetFPV
- 6S 3000mAh: https://oscarliang.com/product-0j2q
- 6S 6000mAh: https://oscarliang.com/product-h4hg
My original plan was to put this battery to the test on my 7″ FPV drone and fixed wings. Unfortunately, the weather has been uncooperative, and these long-range flights typically last an hour or more making it hard to find a window for testing. As I’ll be away for some time, I’ll have to postpone further testing until my return. For now, I’m sharing the data I’ve collected so far.