While many experts recommend using LIION packs for long-range flights due to their high energy density, after testing several packs, I found out that they lack performance, featuring only a 10-30C discharge rate. Instead, the Bonka 6S 6000mAh LiPO has 120C discharging, providing enough power for the most challenging flight movements.
Bonka’s U2 FPV series includes capacities from 300 to 9700mah and discharge rates from 45C to 180C, covering a wide range of FPV drones. Their product palette also includes RC Car, Helicopter, Airplane, RC Transmitter, and Airsoft Gun batteries.
The Bonka 6S 6000mAh U2 batteries are close to 16cm long, making them suitable only for 9-inch and larger drones.
Bonka FPV 6S 6000mAh 120C battery from MyLiPO.de
Disclosure: I received this long-range LIPO pack in a product review collaboration with MyLiPO. Although the battery was offered for free, all opinions in this article remain mine, and the sponsor did not influence me. MyLIPO is the official distributor of Bonka Power batteries in Germany.
In addition to the Bonka 6S/6000mAh battery, MyLIPO sent me four of their Velcro bands, a pair of 25cm and one of 30cm. Of all the battery straps I have used over the last 10 years of droning, these rubberized Kevlar battery straps seem to have the best quality.
The Bonka 6S 6000 U2 is available with three discharge plug types (XT60, XT90, AS150) or without any, as the review unit I received. The battery pack comes with thick 8AWG (⌀3mm) main leads, making it difficult to solder XT60 connectors. 
As you can see in the picture above, the battery is quite big. It measures 156*55*49mm and weighs 878 grams. The battery adopts standard 6S1P configuration, meaning that the six cells inside the pack are serially soldered. Storage voltage is 22.8V (3.8V/cell), and you can charge it up to 25.2V (4.2v/cell).
Technical parameters
| Model number | BKU2-6000/PSN-6S FPV |
| Cell combinations | 6S1P |
| Capacity | 6000mAh |
| Voltage | 22.2V / 6S |
| Power | 133.2Wh |
| Max discharge rate | 120C (720A) |
| Output cable | 8AWG (no plug, or optional XT60, XT90, AS150) |
| Balance connector | JST / XH |
| Size | 49 x 55 x 156mm |
| Weight | 878 grams |
| Suitable for | CineLifter and 7-10″ FPV drones |
Pricing and availability
The Bonka 6S 6000mAh LR LIPO battery can be ordered from MyLiPo.de for €159. The Kevlar LIPO straps shown in this review are priced at €3.20 (five size options). Before ordering, I suggest you ask about delivery options, as batteries over 100Wh are regulated as hazardous materials in many countries.
Bonka 6S 6000mAh FPV LIPO: Performance and Test Results
One of the most important quality factors of a LIPO pack is the internal resistance (IR). A healthy battery has similar cell IR across the pack. A lower IR means the battery can more effectively deliver power to your FPV drone.
A healthy battery has similar individual cell IR across the pack. The higher the cell’s capacity, the lower the internal resistance should be. For example, this Bonka 6000mAh has 2-3mΩ/cell, and a 650Ahm has 10-15mΩ/cell. For capacities over 5000mAh, it would be ideal to have 1mΩ/cell (1 milliohms/cell).
At higher temperatures, the internal resistance of LIPO batteries decreases, which can result in higher power output. This is why it is important to pre-heat them before use during the winter. As batteries age, their internal resistance increases. A high IR indicates that it is time to retire them.
Before testing, I performed five cycles of charging/discharging at 0.5C (3A). I tested the Bonka 6S 6000mAh with my long-range iFlight Chimera 9 drone. While using LIION packs, I constantly receive low-voltage alarms; the BONKA performed bravely despite being 250 grams heavier. With my setup, which had a 1650-gram take-off weight, the flight time averaged around 25 minutes. After nearly 50 cycles on our test battery, it still puts out plenty of power while under load, just like a new pack should. I’m also using this BONKA battery to charge smaller batteries. The 133Wh capacity allows charging 12-14 pieces of 4S 650mA batteries.
Thanks to the 120C discharge rate, the Bonka 6S 6000mAh LIPO can deliver 720A (6Ax120), so I did not encounter any power shag (high voltage drop) during the test flights. The pack remained cold while charging, discharging, and flights. Note: Li-Po and Li-Ion batteries should NEVER be charged, balanced, or discharged unattended. ALWAYS use fireproof bags to store and charge/discharge them. Mishandling of FPV batteries can lead to fire, explosions, and toxic smoke inhalation.
Bonka 6S 6000mAh LIPO vs FullSend 6s 6000mAh LiION
If you are looking for a long-range FPV drone battery, you must choose between LIPO and LIION batteries. In the table below, I compared the Bonka 6S LIPO with the FullSend 6S LIION pack.
| FullSend 6s 6000mAh | Bonka 6S 6000mAh | |
| Chemistry | Lithium-ion | Lithium polymer |
| Cell connection | 6S2P | 6S1P |
| Max discharge rate | 35C | 120C |
| Minim discharge voltage | 2.5V | 3.2V |
| Energy density | 1W/4.56 grams | 1W/6.6 grams |
| Size | 137*56*38mm | 156*55*49mm |
| Weight | 608 grams | 878 grams |