Lithium-ion (Li-ion) batteries are gaining popularity in FPV for their impressive energy density, offering significantly longer flight times compared to traditional LiPo packs. In this review, I’ll test some of Auline’s latest Li-ion offerings—the V45 6S 3000mAh and S70 6S 4500mAh—and compare them to their previous generation as well as other well-known packs, including Lumenier’s 6S 3000mAh and my personal favorite, the Molicel P28A.
Learn more about Li-ion batteries and how they compare to LiPo in this detailed guide: https://oscarliang.com/li-ion-battery-long-range/#Differences-Between-LiPo-and-Li-ion-Batteries
Table of Contents
Where to Buy
Auline offers two series of Li-ion packs:
- V45: Uses 18650 cells – more compact and lightweight, with a maximum discharge current of 45A
- S70: Uses 21700 cells – larger and heavier, but with a significantly higher discharge current of 70A
Left: V45 6S; Right: S70 6S
In this review, I’ll focus on the 6S variants of both versions, as 6S is currently the most popular configuration in modern FPV drones.
Get the Auline V45 6S 3000mAh Li-ion from:
Buy the Auline S70 6S 4500mAh Li-ion from:
Why Choose Li-ion over LiPo?
Li-ion batteries offer a higher energy-to-weight ratio than typical LiPo packs, which translates to longer flight times for the same weight. However, they come with a trade-off—lower C-rating, meaning they can’t deliver as much current. That’s why Li-ion packs aren’t suitable for high-power applications like freestyle or racing.
But for long-range FPV, where efficiency and endurance matter more than raw power, Li-ion batteries are a perfect match. These types of drones typically draw low current, making Li-ion the ideal choice.
Specifications
V45:
- Cell Type: 18650 Li-ion
- Cell Configuration: 6S1P
- Nominal Voltage: 22.2V (3.6V per cell)
- Max Voltage (Fully Charged): 25.2V (4.2V per cell)
- Rated Capacity: 3000mAh
- Max Continuous Discharge Current: 45A
- Recommended Charge Current: 3A (1C)
- Battery Plug: XT60
- Dimensions: 73 × 56 × 38mm
- Weight: 314g (~50g per cell)
S70:
- Cell Type: 21700 Li-ion
- Cell Configuration: 6S1P
- Nominal Voltage: 22.2V (3.6V per cell)
- Max Voltage (Fully Charged): 25.2V (4.2V per cell)
- Rated Capacity: 4500mAh
- Max Continuous Discharge Current: 70A
- Battery Plug: XT60
- Dimensions: 78 × 65 × 44mm
- Weight: 428.7g (~68g per cell)
Auline S70 6S 4500mAh Pack
The battery arrived well-packaged in bubble wrap inside a sturdy cardboard box, ensuring excellent protection during shipping.
Construction remains similar to the previous version: simple and minimal to reduce weight. Each pack features soft foam tape on top and bottom, and a dual-layer PVC heatshrink wrap. The switch from black to white heatshrink is a welcome change—white tends to stay less warm under direct sunlight, which is helpful when flying in hot weather.
Each battery is clearly labeled with detailed specs, including configuration, capacity, max discharge current, nominal voltage, and total watt-hours. It comes with a standard 6S balance lead and an XT60 discharge connector.
Auline hasn’t disclosed the exact cell model used in the S70, but they claim these are premium 4500mAh 21700 cells with a 70A maximum current. This is a substantial improvement over the previous version, which was rated at 4000mAh and 45A.
To support the higher current rating, the discharge leads have been upgraded from 16AWG to thicker 14AWG wires, and the length has been extended slightly to about 7.5cm. The battery is also heavier—428g versus the previous 398g. This may be due to both the improved cells and the thicker wiring.
It’s important to note that these batteries do not include onboard BMS (battery management systems). While BMS protection is useful in other applications, it’s not suitable for FPV drones, as a sudden power cutoff mid-flight (which a BMS would trigger to protect the cells) could result in a crash.
Here’s a size comparison with a typical 6S 1100mAh LiPo battery for reference—these Li-ion packs are slightly larger but offer over 4 times the capacity!
Capacity
To verify the true capacity, I performed a controlled discharge test from 4.2V to 2.7V per cell at 0.5C. This low discharge rate ensures minimal heat buildup and delivers a more accurate reading of usable capacity.
Measured capacity: 4442mAh.
Discharge Performance
In terms of C-rating, the new Auline S70 performed significantly better than the previous version. Throughout most of the discharge curve, it maintained around 0.8V less voltage sag, meaning your drone can pull more power during flight, it should feel more responsive, agile and powerful.
Toward the final third of the discharge cycle, the performance gap widened even further. The S70 lasted longer before reaching 2.9V, indicating not just better power delivery but also increased total flight time.
Auline V45 6S 3000mAh Pack
The V45 pack features essentially the same construction and build quality as the 4500mAh S70, but it’s noticeably smaller and lighter due to the use of 18650 cells instead of the larger 21700 cells. That’s also why its maximum continuous discharge current is lower—rated at 45A.
The V45 weighs about the same as the Lumenier 6S 3000mAh Li-ion pack we previously reviewed, but it appears slightly more compact thanks to Auline’s more space-efficient packaging.
Here’s a size comparison to a typical 6S 1100mAh LiPo battery for perspective—it’s bulkier, of course, but offers over 2.5 times the capacity in return.
Capacity
For the Auline V45 6S 3000mAh, I performed the same controlled discharge test as with the S70, from 4.2V to 2.7V per cell at 0.5C. The measured capacity came in at 2991mAh, which is essentially spot-on with the rated value—very impressive consistency.
Discharge Performance
The performance gap between the Auline V45 and the older Lumenier pack is substantial—it’s like night and day. Voltage sag is significantly reduced, and power delivery remains more stable throughout the discharge cycle.
In fact, the Auline V45 even outperformed the Molicel P28A in my testing—widely considered one of the best 18650 cells for high-performance FPV use. That’s an outstanding result and makes the V45 stand out as one of the best 18650-based Li-ion packs currently available.
Final Thoughts
From capacity to discharge performance, Auline’s latest V45 and S70 Li-ion batteries are top-tier. Compared to previous Auline models and competitors like Lumenier, they deliver substantial improvements in both C-rating and capacity. If you’re looking for a ready-to-use Li-ion battery to maximize flight time without sacrificing reliability, these are easily among the best you can get today.
That said, they aren’t cheap. You can build your own Li-ion battery packs and potentially save money. Here’s a DIY tutorial if you want to try that route: https://oscarliang.com/li-ion-battery-long-range/
My go-to 18650 cells have been the Molicel P28A and P30B cells. They’re well-known for their high discharge performance and have served me reliably for long-range flying. You can find my full comparison and testing results here: https://oscarliang.com/best-18650-li-ion-battery/
Still, building your own pack takes time, and there’s always some risk involved when soldering directly to cells. For many pilots—especially those short on time or looking for peace of mind—buying an off-the-shelf pack like the V45 or S70 is a more practical choice.
You can get the Auline V45 6S 3000mAh Li-ion from:
Buy the Auline S70 6S 4500mAh Li-ion from:
Which One to Choose?
V45 is ideal for smaller builds such as cinewhoops, 4-inch long-range, and lightweight 5-inch drones where power and payload capacity are limited.
S70, on the other hand, offers more punch and capacity—perfect for more powerful 5-inch, 6-inch, and 7-inch long-range quads that demand higher current draw and longer endurance.
7 comments
Hey Oscar, first of all thank for all the work,
I’ve got a 5inch ~440g dry weight that run on 2207 1960KV and HQ R37 props, and I usually run 1300mah 6s 150C (~210g). Would the Auline V45 6S 3000mAh Li-ion work on this config for cruising flights ? I still haven’t used any li-ion batteries at all so i’m a bit unsure of it all !
When trying to charge my new 3S 3000 mAh Auline Li Ion packs, even at the recommended 0.5C for 1.5A, my ToolkitRC Q6AC charger gives error messages. Oscar, have you tried your Q6AC with these Auline Li Ion packs?
What error exactly? Is your charger reading voltage from all 3 cells through the balance lead?
I test one individual AuLine 45A 3000 mAh, 3S Li-ion battery the charger’s 4 ports, one at a time.
I plug it into channel 1, 2, 3, or 4 and set Li-ion, 3S, 4.20, 1.5 amp. I power cycle between tests.
Ch1 Low Battery Voltage
Ch2 is OK
Ch3 is OK
Ch4 Balance Port Voltage Match Error!
I can repeat this and get the same results. Ch1 and Ch4 seem to have problems. I am running the lastest firmware 1.06.
It seems to be hit and miss. My other comment suggests that Ch1 and Ch4 have problems. However, when I test a second identical 3S pack, I get
Ch 1 OK
Ch 2 High battery voltage!
Ch 3 Low battery voltage!
Ch 4 OK
My iSDT K2 Air charger has no problems at all with these Auline 3S 3000 mAh Li Ion batteries. Also, this Q6AC charger has no problems with a Auline 4S 3000 mAh Li Ion pack. This is a head scratcher. Something in the Q6AC firmware is too sensitive to the voltages on the balance pins.
Check the balance connector (pin by pin) with a multimeter and see if the readings are normal? Also try wiggle the balance lead when measuring to rule out loose connections/solder joints inside the pack.
If battery is fine then it’s probably the charger, or the balance port – check with reseller and see if you can get a replacement.
Thanks for your comments. Using a Tenergy 5-in-1 Cell Meter I measured the balance lead wire voltages against ground for the 2 of my Auline 3S 3000 mAh Li-ion batteries, after I put a storage charge onto them with my iSDT K2 Air:
Battery 1: 3.796v, 3.804v, and 3.798v
Battery 2: 3.798v, 3.796v, and 3.800v
Granted, these voltages are without any current loads.
Then I tried charging them with the Q6AV and got errors as usual. I get zero errors with the iSDT K2 Air.