2S 20A BMS Li-Ion Battery Protection Board Price in Bangladesh

The 2S 20A BMS Li-Ion Battery Protection Board is a compact battery management and protection module designed for two lithium-ion cells or cell groups connected in series. It is commonly used when building rechargeable battery packs that require basic electronic protection against conditions such as overcharging, excessive discharge, overcurrent, and short circuits.

A 2S lithium-ion battery configuration consists of two individual cells or cell groups connected in series. With typical 3.7V nominal Li-ion cells, a 2S pack has a nominal voltage of approximately 7.4V and reaches approximately 8.4V when fully charged. Because two cells are connected in series, monitoring the individual cell voltages is important rather than relying only on the total pack voltage.

The BMS monitors the voltage of the cells through its balance or sensing connections. When a cell reaches an unsafe voltage condition, the protection circuit can disconnect the battery from the charger or load according to the board’s protection thresholds.

The 20A rating indicates the board’s intended current-handling capability under its specified conditions. However, the actual usable current depends on the particular PCB design, MOSFETs, temperature, wiring, battery cells, connector quality, and duration of the load. A 20A label should therefore not automatically be interpreted as meaning that every battery pack can safely deliver 20A continuously.

One of the major benefits of using a BMS is that it adds an electronic layer of protection to a lithium-ion battery pack. Lithium-ion cells require controlled charging and discharging. Operating cells beyond their specified voltage range can damage the cells and may create significant safety hazards.

The 2S 20A BMS can be useful in applications such as DIY battery packs, portable electronics, LED lighting, robotics, small power systems, backup systems, cordless equipment, and other compatible 7.4V lithium-ion applications.

The board is intended specifically for 2S Li-ion battery configurations. It should not be used interchangeably with a BMS designed for 3S, 4S, or another series count. The number of series cells is a fundamental characteristic of a BMS because the protection circuit must monitor the appropriate individual cell voltages.

It is also important to distinguish a BMS from a charger. The BMS protects and manages the battery pack, but it does not necessarily replace a proper lithium-ion charging circuit. A 2S Li-ion battery pack requires an appropriate 8.4V CC/CV charging source matched to the pack and the BMS.

When assembling a battery pack, the two cells or cell groups should ideally have matching specifications and similar state of health. Significant differences between cells can cause imbalance, reducing the usable performance of the pack and causing one cell to reach its voltage limit earlier than the other.

For applications requiring balanced charging, users should verify whether the particular 2S 20A board is a balancing BMS or protection-only BMS, as features vary between board versions.

Overall, the 2S 20A Li-ion BMS Protection Board is a practical and compact solution for adding essential protection circuitry to compatible two-cell series lithium-ion battery packs.

What is a 2S BMS?

A 2S BMS (Battery Management System) is an electronic protection circuit designed for a battery pack containing two cells or cell groups connected in series.

The “2S” designation means:

• 2 = two series-connected cell groups
• S = series

For typical 3.7V nominal Li-ion cells:

• Single cell nominal voltage: approximately 3.7V
• 2S nominal pack voltage: approximately 7.4V
• Fully charged 2S voltage: approximately 8.4V

The BMS monitors the individual cell groups and controls the connection between the battery and external charger/load.

Key Features of 2S 20A BMS Li-Ion Protection Board

• Designed for 2S Li-ion battery packs
• 20A-class current capability
• Overcharge protection
• Over-discharge protection
• Overcurrent protection
• Short-circuit protection
• Individual cell voltage monitoring
• Compact PCB design
• Suitable for rechargeable lithium-ion packs
• Useful for DIY battery construction
• Suitable for portable power projects
• Helps protect connected Li-ion cells
• Suitable for 7.4V nominal battery systems
• Compatible with properly matched 18650 and other suitable Li-ion cells
• Simple battery-management solution

Technical Specifications

• Product Type: Li-ion BMS / Battery Protection Board
• Configuration: 2S
• Battery Chemistry: Lithium-Ion
• Nominal Battery Voltage: 7.4V
• Full-Charge Voltage: 8.4V
• Maximum Rated Current: Up to 20A
• Protection: Overcharge / Over-discharge / Overcurrent / Short Circuit
• Cell Count: 2 Series
• Application: 2S Rechargeable Li-ion Battery Packs
• PCB Type: Compact Protection Circuit Board

Important: Exact specifications such as overcharge detection voltage, over-discharge detection voltage, overcurrent threshold, short-circuit response, balancing current, standby current, and maximum continuous current can vary between manufacturers and PCB versions. Always verify the markings and datasheet of the exact board before designing a battery pack.

Working Principle of 2S 20A BMS

The 2S BMS monitors the voltage of the two series-connected battery sections.

During charging, the BMS monitors the cell voltages. If one of the cells reaches its specified overcharge threshold, the protection circuit can disconnect the charging path to prevent further charging.

During discharge, if a cell falls below its specified minimum voltage, the BMS can disconnect the load to help prevent excessive discharge.

The overcurrent protection monitors the current flowing through the battery circuit. If the current exceeds the board’s specified threshold, the protection circuit can disconnect the output.

In the event of a short circuit, the BMS can rapidly disable the battery output depending on the design of the protection circuit.

These functions work together to provide a layer of protection between the lithium-ion cells and the external circuit.

Applications of 2S 20A BMS Li-Ion Battery Protection Board

• 2S 18650 battery packs
• 2S 21700 battery packs
• 7.4V rechargeable battery systems
• DIY portable power supplies
• Robotics projects
• RC electronics
• LED lighting systems
• Portable electronics
• Small UPS systems
• Backup power projects
• DIY battery-powered equipment
• IoT devices
• Electronics prototypes
• Engineering projects
• Educational battery projects

Advantages

• Provides essential battery protection
• Supports 2S lithium-ion configurations
• Compact and easy to integrate
• Helps prevent overcharging
• Helps prevent excessive battery discharge
• Provides overcurrent protection
• Provides short-circuit protection
• Suitable for DIY battery packs
• Works with compatible cylindrical Li-ion cells
• Useful for portable and embedded applications
• Helps improve battery-pack operating safety

Limitations

• Designed specifically for 2S Li-ion configurations.
• It should not be used with LiFePO4 cells unless the specific board is explicitly designed for that chemistry.
• A BMS is not a substitute for the correct battery charger.
• The actual continuous current capability depends on the PCB, MOSFETs, wiring, connectors, and thermal conditions.
• Not every 2S BMS provides active or passive cell balancing.
• Incorrect wiring can damage both the BMS and battery cells.
• The battery cells should be appropriately matched.

Installation / Usage Tips

• Confirm that the battery pack is a 2S Li-ion configuration.
• Use two compatible cells or two matched cell groups.
• Verify cell polarity before making any connection.
• Follow the PCB’s B-, B1/BM, and B+ markings if those terminals are provided.
• Connect the cell junction to the designated middle/series-sense terminal.
• Connect the external load and charger according to the board’s P+/P− or equivalent markings.
• Double-check every connection before applying power.
• Use an 8.4V CC/CV Li-ion charger appropriate for a 2S pack.
• Do not connect an unsuitable charger.
• Use appropriate wire thickness for the expected load current.
• Keep the PCB insulated from conductive metal surfaces.
• Do not short-circuit the battery pack.
• Test individual cell voltages before final assembly.
• For high-current applications, ensure adequate cooling and suitable connectors.

Why Choose 2S 20A BMS Li-Ion Battery Protection Board?

The 2S 20A BMS Li-ion Protection Board is a useful choice for battery builders who need a compact protection circuit for a two-cell series lithium-ion battery pack. It provides multiple protection functions in a small PCB and can be integrated into a wide variety of 7.4V nominal battery systems.

Whether you are building a DIY power supply, robotics battery, portable electronics project, LED system, or other compatible battery-powered device, a properly selected BMS can provide an important protection layer for the battery pack.

Why Buy from Electroxbd?

• 100% Quality Tested Products
• Trusted Source for Reliable Electronic Parts
• Fast Delivery Across Bangladesh
• Competitive Pricing
• Quality Battery Management Products
• Dedicated Technical Support
• Nationwide Delivery Across Bangladesh
• Suitable for Students, Engineers, Technicians and DIY Makers

Frequently Asked Questions (FAQ)

What is the voltage of a 2S Li-ion battery pack?

A typical 2S Li-ion pack has a 7.4V nominal voltage and reaches approximately 8.4V when fully charged.

What does 20A mean on this BMS?

The 20A designation refers to the board’s rated current capability. Actual safe continuous current depends on the specific board design, MOSFET temperature, wiring, connectors, battery cells, and operating conditions.

Can I use this BMS with LiFePO4 batteries?

Not unless the specific BMS is explicitly designed for LiFePO4 chemistry. A standard 2S Li-ion BMS has different voltage-protection thresholds from a LiFePO4 BMS.

Does the 2S 20A BMS charge the battery?

The BMS manages and protects the battery during charging, but it is not a replacement for an 8.4V Li-ion charger. Use a proper 2S lithium-ion CC/CV charger.

Can I use 18650 or 21700 cells with this BMS?

Yes, provided the cells are compatible Li-ion cells and the completed pack is configured as 2S. The physical cell format does not determine the BMS series count; the electrical configuration does.

Where can I buy the 2S 20A BMS Li-ion Battery Protection Board in Bangladesh?

You can buy the 2S 20A BMS Li-ion Battery Protection Board from Electroxbd, a trusted supplier of electronic components, modules, batteries, and DIY electronics products in Bangladesh.

Common Questions:
What is the price of 2S 20A BMS Li-Ion Battery Protection Board in Bangladesh?
The latest price of 2S 20A BMS Li-Ion Battery Protection Board in Bangladesh is 80BDT.
Where to buy 2S 20A BMS Li-Ion Battery Protection Board in Bangladesh?
You can buy the 2S 20A BMS Li-Ion Battery Protection Board at the best price from ElectroXBD in Bangladesh.

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