The CNHL Long Range Series 6350mAh 14.4V 4S1P 21700 Li-ion battery combines four BAK 65E high-energy cells into a compact 91.44Wh power system for efficient RC airplanes, fixed-wing aircraft and endurance-oriented UAVs using XT90. The 65E platform is designed around maximum stored energy and high gravimetric energy density rather than extreme burst output.
At approximately 329.5g for the pictured production sample, the finished battery achieves approximately 278Wh/kg of pack-level energy density. This figure includes the complete battery assembly, XT90 connector, 12AWG power leads and balance wiring.
This XT90 configuration is positioned primarily for efficient fixed-wing RC airplanes and UAV systems where endurance and stored watt-hours matter more than repeated high-current output. XT90 does not increase the capability of the underlying 65E cells compared with the corresponding XT60 version; connector choice should follow the aircraft's existing electrical system.
Quick Battery Fit & Performance Check
| Battery Type |
21700 Li-ion battery pack |
| Cell Platform |
BAK 65E |
| Configuration |
4S1P / 4 cells |
| Capacity |
6350mAh |
| Nominal Voltage |
14.4V |
| Nominal Pack Energy |
91.44Wh |
| Approx. Weight |
Approx. 329.5g |
| Approx. Pack Energy Density |
Approx. 278Wh/kg |
| Main Connector |
XT90 |
| Power Wire |
12AWG |
| Performance Direction |
Energy First / Maximum Endurance |
| Primary Applications |
RC airplanes, fixed-wing aircraft and efficient UAV systems |
Product Specifications
| SKU |
LI635104S70XT90 |
| Series |
CNHL Long Range Series |
| Chemistry |
Rechargeable Li-ion |
| Cell Format |
21700 |
| Cell Model |
BAK 65E |
| Configuration |
4S1P / 4 cells |
| Capacity |
6350mAh |
| Nominal Voltage |
14.4V |
| Nominal Pack Energy |
91.44Wh |
| Main Connector |
XT90 |
| Main Power Wire |
12AWG |
| Approx. Dimensions |
73.5 × 43.5 × 43.5mm (2.89 × 1.71 × 1.71in) |
| Approx. Weight |
329.5g / 0.73lb |
| Approx. Pack Energy Density |
Approx. 278Wh/kg |
91.44Wh at Only About 329.5g
The defining specification of this battery is the relationship between stored energy and finished pack weight. With 91.44Wh of nominal energy at approximately 329.5g, the pack delivers roughly 278Wh/kg.
This is a finished-pack value rather than a bare-cell calculation. It includes the complete four-cell assembly, XT90 connector, 12AWG power leads, balance wiring and pack construction.
For fixed-wing aircraft and UAVs, this matters because every gram of battery must be carried throughout the flight. A high pack-level Wh/kg allows more mission energy to be added without battery mass increasing at the same rate.
Approx. 278Wh/kg Finished-Pack Energy Density
The BAK 65E is already a very high-energy cell platform, and much of that advantage remains after assembly into the finished battery. LI635104S70XT90 retains approximately 278Wh/kg at pack level.
This makes energy density a central performance characteristic of the product rather than merely another specification. Efficient airplanes and fixed-wing UAVs can potentially translate that favorable energy-to-weight ratio into longer useful operating time.
Actual endurance still depends on aircraft efficiency, propulsion setup, payload, weather, battery placement and usable depth of discharge.
27% More Energy with Only About 11% More Weight
The difference becomes clear when this 65E pack is compared with the corresponding CNHL 5000mAh 50D 4S1P XT90 battery.
| Specification |
5000mAh 50D XT90 |
6350mAh 65E XT90 |
| Pack Energy |
72Wh |
91.44Wh |
| Approx. Weight |
296.5g |
329.5g |
| Pack Wh/kg |
Approx. 243Wh/kg |
Approx. 278Wh/kg |
| Performance Direction |
Power + Energy Balance |
Energy First / Maximum Endurance |
The 65E version stores approximately 27% more nominal energy, while the pictured finished-pack weight increases by only about 11.1%. This produces approximately 14.3% higher finished-pack gravimetric energy density.
The 65E version is therefore not simply a larger-capacity version of the 50D pack. It represents a different optimization target: maximum energy for each kilogram of battery carried.
Powered by BAK 65E – Energy First / Maximum Endurance
The BAK 65E is the energy-focused platform in the CNHL 21700 Long Range family. Its advantage is high stored energy relative to cell mass rather than maximizing burst-current capability.
That design direction fits efficient fixed-wing aircraft especially well. Once established in cruise, many airplanes require relatively modest propulsion power, giving the battery more opportunity to convert stored watt-hours into useful distance and flight time.
Aircraft with repeated high-current demand should be matched more conservatively to the battery platform rather than selecting the 65E purely because it has higher capacity.
4S1P High-Energy Architecture
LI635104S70XT90 uses only four 21700 cells in a 4S1P configuration while providing 6350mAh capacity and 91.44Wh of nominal pack energy.
This keeps the pack significantly lighter and more compact than a 4S2P architecture while still providing a high energy budget. For weight-sensitive aircraft, that can be more valuable than simply maximizing total mAh.
Because the pack remains 1P, electrical load is not shared across parallel cells. Current demand therefore needs to remain appropriate for the energy-oriented 65E platform.
4S High-Energy Li-ion Battery for RC Airplanes
This XT90 version is positioned primarily for efficient 4S RC airplanes and fixed-wing aircraft where long flight duration and stored energy are more important than repeated high-current output.
Gliders, sailplanes, endurance-oriented utility aircraft and other efficient fixed-wing models can be strong application directions when takeoff, climbing and full-throttle current remain appropriate for the 65E platform.
Browse additional options in the CNHL Li-ion batteries for RC airplanes and fixed-wing aircraft collection.
Strong Energy-to-Weight Performance for Gliders and Sailplanes
Electric gliders and sailplanes are particularly interesting applications for a high-energy 65E battery because much of the flight may occur with very low propulsion power once altitude has been gained.
The approximately 278Wh/kg finished-pack energy density gives an appropriately sized aircraft substantial onboard energy without moving to an eight-cell 4S2P configuration.
Motor-on climbing current, battery placement, final CG and landing weight must still be verified for the specific model.
4S Li-ion Battery for Fixed-Wing UAVs
Fixed-wing UAVs can also make strong use of this battery because aerodynamic efficiency allows more of the available 91.44Wh to be devoted to useful mission time rather than continuously generating lift through propulsion.
Mapping, inspection and surveying aircraft can benefit when the complete UAV is designed around the pack's 4S voltage platform, current capability, physical dimensions and installed battery mass.
Explore additional endurance-oriented products in the CNHL Li-ion UAV battery range.
XT90 Connector with 12AWG Power Leads
LI635104S70XT90 uses an XT90 main connector with 12AWG power leads, making it a natural configuration for fixed-wing and UAV systems already standardized around XT90.
The XT90 connector does not increase the fundamental capability of the BAK 65E cells compared with the corresponding XT60 version. Both batteries use the same four-cell 4S1P architecture.
Choose XT90 because it matches the aircraft's electrical ecosystem, not because it represents a higher-performance cell configuration.
Compact 73.5 × 43.5 × 43.5mm Pack Size
Despite storing 91.44Wh of nominal energy, the finished battery measures approximately 73.5 × 43.5 × 43.5mm. Its four-cell 4S1P structure keeps the pack compact compared with higher-capacity 4S2P alternatives.
Before purchase, measure the usable battery compartment and allow additional clearance for the XT90 connector, 12AWG wiring, balance lead, securing straps and airflow. For fixed-wing use, always verify center of gravity after installation.
6350mAh 4S1P vs 12700mAh 4S2P
| Configuration |
Main Advantage |
Fixed-Wing / UAV Direction |
| 6350mAh 4S1P |
Very high energy density with only four cells |
Weight-sensitive airplanes, gliders and efficient fixed-wing UAVs |
| 12700mAh 4S2P |
Twice the parallel capacity plus load sharing |
Larger fixed-wing and UAV platforms capable of carrying more battery mass |
The 2P version provides much more total energy, but the 1P battery can deliver better overall aircraft efficiency when reducing installed battery mass is more important than maximizing capacity.
Part of the CNHL 4S 21700 Long Range Platform
This battery belongs to the CNHL 4S 21700 Li-ion battery range, where 5000mAh, 6350mAh, 10000mAh and 12700mAh configurations cover different balances of power, energy and installed battery mass.
It is also part of the CNHL Long Range Series, designed around endurance-focused cylindrical Li-ion battery technology.
For wider comparison, explore all CNHL 21700 Li-ion batteries or the complete CNHL Li-ion battery range.
Charging and Battery Safety
Use charging equipment and settings appropriate for the exact finished Li-ion battery specification. Follow the final published charge-voltage and charge-current limits for this BAK 65E pack rather than assuming that settings from another Li-ion, LiPo or LiHV battery are interchangeable.
The 65E platform is designed around high stored energy. Do not interpret the 6350mAh capacity or high Wh/kg figure as evidence of high-burst discharge capability. Aircraft propulsion current and battery temperature must remain appropriate for the finished pack.
Inspect the battery, XT90 connector, wiring and wrapping before charging or flight. Do not use a battery that is damaged, excessively hot or electrically abnormal.
During initial aircraft setup, monitor actual propulsion current and battery temperature under realistic operating conditions before relying on the battery for extended-duration flights or missions.
FAQ: CNHL 6350mAh 4S 21700 Li-ion Battery with XT90
What cells are used in this battery?
The battery uses four BAK 65E 6350mAh high-energy 21700 Li-ion cells in a 4S1P configuration.
How much energy does this battery store?
The finished battery is rated at 91.44Wh of nominal pack energy with a 6350mAh capacity and 14.4V nominal product rating.
What is the finished-pack energy density?
Based on the pictured production sample weight of approximately 329.5g and 91.44Wh nominal energy, calculated finished-pack gravimetric energy density is approximately 278Wh/kg.
Why is this battery more energy-dense than the 5000mAh XT90 version?
The BAK 65E is an energy-focused cell platform. Compared with the corresponding 5000mAh 50D 4S1P XT90 battery, this pack stores approximately 27% more nominal energy while the pictured finished-pack weight increases by only about 11.1%.
Is this battery intended for RC airplanes?
Yes. Efficient fixed-wing RC airplanes are the primary application direction for this XT90 configuration, especially where endurance and energy-to-weight performance matter more than repeated high-current output.
Can it be used in a fixed-wing UAV?
Yes. It can suit mapping, inspection, surveying and other endurance-oriented fixed-wing UAVs when the complete aircraft is compatible with the battery's voltage, dimensions, weight and current capability.
Is the XT90 version more powerful than the XT60 version?
No. Both versions use the same BAK 65E cells and 4S1P architecture. XT90 changes the connector ecosystem and slightly increases finished pack weight, but it does not increase the fundamental capability of the cells.
What are the dimensions and weight?
The pictured production battery measures approximately 73.5 × 43.5 × 43.5mm and weighs approximately 329.5g.
What connector and wire does it use?
LI635104S70XT90 uses an XT90 main power connector with 12AWG leads.
Does higher capacity mean higher discharge power?
No. The 6350mAh 65E platform is optimized around stored energy and endurance. Higher capacity should not be interpreted as greater discharge capability than a more power-oriented cell platform.
