Description
BAK 2S 7.4V 55000mAh 2S11P 3C Lithium-Ion Battery Pack | Rechargeable NMC Battery
The BAK 2S 7.4V 55000mAh 2S11P 3C Lithium-Ion Battery Pack is a high-capacity rechargeable NMC lithium-ion battery pack designed for applications requiring a compact 7.4V-class power source with high energy capacity and strong discharge capability.
This battery pack uses BAK 21700 5000mAh cells arranged in a 2S11P configuration, providing 55Ah / 55,000mAh capacity. The pack has a nominal voltage of 7.4V and a maximum charging voltage of 8.4V.
With 3C-rated cells, the theoretical cell-based discharge capability is up to 165A, although the actual usable continuous current depends on the BMS, wiring, connectors, cell specifications, thermal management and complete pack construction.
Key Features
- Brand: BAK
- Battery Chemistry: NMC Lithium-Ion
- Cell Type: 21700
- Cell Capacity: 5000mAh
- Configuration: 2S11P
- Pack Capacity: 55Ah / 55,000mAh
- Nominal Voltage: 7.4V
- Maximum Charge Voltage: 8.4V
- Cell Discharge Rating: 3C
- Total Cells: 22
- Rechargeable lithium-ion battery
- High-capacity 55Ah configuration
- Suitable for high-current applications
- BMS and connector options can be customized
2S11P Battery Configuration
The battery contains 22 BAK 21700 cells arranged as 2S11P:
- 2 cells/groups in series
- 11 cells in parallel
- 11 × 5000mAh = 55,000mAh / 55Ah
- 2 × 3.7V = 7.4V nominal
- 2 × 4.2V = 8.4V maximum charge voltage
- Nominal energy = 7.4V × 55Ah = 407Wh
The 11P configuration increases the available capacity while the 2S configuration provides the 7.4V nominal pack voltage.
3C Discharge Capability
Based on the 55Ah capacity:
55Ah × 3C = 165A theoretical current
The actual allowable continuous current should be determined from the complete battery design, including:
- BAK cell specifications
- BMS current rating
- Busbars/nickel strip
- Wire gauge
- Connector rating
- Pack construction
- Operating temperature
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 should be selected according to the required load current and application.
Connector & Wire
The battery can be supplied with application-specific connectors and wiring.
Available options may include:
- XT60
- XT90
- DC connectors
- JST connectors
- Custom power connectors
- Custom wire lengths
- Separate charging/discharging connectors
Applications
- Portable Power Equipment
- Robotics
- RC Systems
- Drones and UAVs
- Industrial Electronics
- Backup Power Systems
- Portable Instruments
- CCTV & Security Equipment
- Custom Battery Projects
- OEM Battery Packs
- High-Capacity Electronic Equipment
Advantages
- 55Ah high-capacity battery pack
- BAK 21700 NMC cells
- 2S11P configuration
- Approx. 407Wh energy capacity
- 3C-rated cell configuration
- Rechargeable lithium-ion technology
- Custom BMS and connector options
- Suitable for OEM and custom battery applications
Package Includes
- 1 × BAK 2S 7.4V 55000mAh 2S11P Lithium-Ion Battery Pack
- 2S BMS according to selected configuration
- Output/charging connector as specified
- 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 charger, LiFePO₄ charger, or another incompatible charger.
Always verify the charger voltage, charging current, BMS rating and battery specifications before charging.



