Description
BAK 2S 7.4V 35000mAh 2S7P 3C Lithium-Ion Battery Pack | Rechargeable NMC Battery
The BAK 2S 7.4V 35000mAh 2S7P 3C Lithium-Ion Battery Pack is a high-capacity rechargeable NMC lithium-ion battery pack designed for applications requiring a compact 7.4V power source with high energy capacity and strong discharge performance.
Built using BAK 21700 5000mAh cells, this battery uses a 2S7P configuration, combining 2 cells/groups in series and 7 cells in parallel per group. The pack provides approximately 7.4V nominal voltage, 8.4V maximum charging voltage, and 35Ah capacity.
With a 3C cell discharge rating, the selected cells are suitable for applications requiring higher current output, subject to the BMS, wiring, connectors and complete pack design.
Key Features
- Brand: BAK
- Battery Chemistry: NMC Lithium-Ion
- Configuration: 2S7P
- Nominal Voltage: 7.4V
- Maximum Charge Voltage: 8.4V
- Capacity: 35Ah / 35,000mAh
- Cell Type: BAK 21700
- Cell Capacity: 5000mAh
- Cell Discharge Rating: 3C
- Total Cells: 14
- Rechargeable battery pack
- High-capacity design
- Suitable for portable and high-power applications
- Custom BMS, connector and wire options available
2S7P Battery Configuration
The pack contains 14 BAK 21700 cells arranged as 2S7P:
- 2 cells/groups in series
- 7 cells in parallel
- 7 × 5000mAh = 35,000mAh / 35Ah
- 2 × 3.7V = 7.4V nominal
- 2 × 4.2V = 8.4V full charge
- Nominal energy: 7.4V × 35Ah = 259Wh
The parallel arrangement increases the available capacity and current capability while the series arrangement establishes the pack voltage.
3C Discharge Capability
At a nominal 35Ah capacity, a theoretical 3C calculation gives:
35Ah × 3C = 105A
This does not mean that every finished battery pack should automatically be operated continuously at 105A. The practical discharge limit should be determined by the selected BMS, cell specifications, nickel/busbar connections, wires, connectors and thermal management.
BMS Protection
A suitable 2S BMS can provide protection against:
- Overcharge
- Over-discharge
- Over-current
- Short circuit
- Cell imbalance
- Temperature-related conditions when temperature sensing is included
The BMS current rating should be selected according to the actual load requirements.
Connector & Wire
Connector and cable specifications can be customized according to the application.
Possible options include:
- XT60
- XT90
- DC connectors
- JST connectors
- Custom power connectors
- Custom wire length
- Separate charge/discharge connections
Applications
- Portable Power Equipment
- Robotics
- RC Applications
- Drones and UAV Systems
- Industrial Electronics
- Medical Equipment
- Backup Power Systems
- CCTV & Security Equipment
- Portable Instruments
- Custom Battery Projects
- OEM Battery Packs
Advantages
- High 35Ah capacity
- BAK 21700 NMC cell technology
- Compact 2S battery configuration
- High theoretical current capability
- Approx. 259Wh energy capacity
- Suitable for demanding rechargeable power applications
- Custom BMS and connector configurations
- Suitable for OEM and custom battery pack requirements
Package Includes
- 1 × BAK 2S 7.4V 35000mAh 2S7P Lithium-Ion Battery Pack
- 2S BMS according to selected configuration
- Output/charging connector according to specification
- Battery wiring and insulation
- Protective packaging/enclosure according to selected design
Important Charging Information
Use an 8.4V Lithium-Ion/NMC charger specifically designed for a 2S NMC battery pack.
Do not use a 12.6V, 8.4V LiFePO₄ or other incompatible charger.
Always confirm the charger current, BMS rating and battery manufacturer’s charging specifications before charging.
