6S 24V 20A Balanced Lithium Battery BMS Protection Board with Equalization for Power Tools & Solar Lighting Systems

SKU: FA2193-14-2
Compatible Battery

6S 22.2V lithium-ion

Full Charge Voltage

25.2V

Continuous Discharge Current

20A

Overcharge Protection Voltage

~4.25V – 4.3V per cell

Over-discharge Protection Voltage

~2.5V – 3.0V per cell

Equalization Function

Yes

Connection Type

Solder pads (spot welding supported)

Module Dimensions

Compact PCB for 6S packs

The 6S 24V 20A Balanced Lithium Battery BMS Protection Board with Equalization is a high-performance safety module designed to protect 6-cell (6S) lithium-ion battery packs from overcharge, over-discharge, and overcurrent conditions. With a 20A continuous discharge rating and equalization (balance) function, this BMS is engineered for moderate to high-drain applications including power tools, solar lighting systems, e-bikes, and energy storage systems where reliable battery safety is essential.

At the heart of the board is a BMS protection circuit that continuously monitors the voltage of each cell and the total pack current, disconnecting the load or charger if any parameter exceeds safe limits. This protects both the battery pack and your connected devices from damage, extending battery lifespan and ensuring safe operation in demanding applications.

The board provides three critical protection functions:

  • Overcharge protection — Disconnects the charger when any cell voltage reaches approximately 4.25V to 4.3V, preventing damage from excessive charging.

  • Over-discharge protection — Disconnects the load when any cell voltage drops to approximately 2.5V to 3.0V, preventing deep discharge that can permanently damage the battery.

  • Overcurrent protection — Disconnects the output when current exceeds 20A, protecting against short circuits and excessive loads.

The 6S configuration means the board manages six cells in series, equalizing (balancing) the voltage across all six cells to ensure they charge and discharge evenly. This cell equalization function is critical for maintaining pack health and maximizing lifespan. Without proper equalization, one cell can become overcharged or over-discharged, leading to premature failure or safety hazards.

The 6S configuration provides a nominal voltage of 22.2V and a full charge voltage of 25.2V, commonly referred to as 24V systems. This voltage range is ideal for power tools, solar lighting systems, e-bikes, and other applications requiring higher voltage than 5S packs.

The 20A continuous rating makes this board suitable for moderate to high-drain applications such as power tools, solar lighting, e-bikes, and portable power stations. This provides reliable performance for a wide range of 6S applications, filling the gap between standard 10A boards and higher-current 40A+ boards.

The board features a solder pad design that supports both direct soldering and spot welding. The exposed pads allow you to solder wires directly to the board, while also being compatible with spot-welded nickel strips for professional battery pack assembly. The board includes B+, B-, BM1 through BM5 (mid-points), P+, and P- pads for battery and output connections.

The wide application range includes:

  • Power tools — High-current protection for drills, saws, and other tools

  • Solar lighting systems — Reliable power for solar street lights and garden lights

  • E-bikes — High-power protection for electric bicycles

  • Energy storage systems — Protect 6S battery packs in solar storage

  • Portable power stations — High-current protection for portable power

  • Electric scooters — Safe power for personal mobility devices

Important Note: This BMS is designed for 6S (6-cell) 24V lithium battery packs with a maximum continuous current of 20A. For higher-current applications, a BMS with a higher current rating should be used. Always verify the voltage and current ratings match your application before installation. Ensure all wiring and connections are rated for the maximum current your application will draw.

Whether you are building a high-power 6S battery pack for a power tool, assembling a solar lighting system, or adding safety protection to an energy storage system, the 6S 24V 20A Balanced Lithium Battery BMS Protection Board provides a reliable solution. It is suitable for individual makers, engineers, and businesses purchasing in bulk for product development or industrial applications.


Features

  • 6S six-cell protection — Manages six cells in series with equalization

  • 20A continuous discharge — Moderate to high-current capability for demanding applications

  • Equalization function — Ensures even charge and discharge across all six cells

  • Comprehensive protection — Overcharge, over-discharge, and overcurrent protection

  • Integrated BMS design — Compact, self-contained protection solution

  • Wide voltage range — 22.2V nominal / 25.2V full charge (24V systems)

  • Solder pad design — Supports both direct soldering and spot welding

  • Wide application range — Power tools, solar lighting, e-bikes, energy storage


Technical Specifications 

# Parameter Specification
1 Compatible Battery 6S 22.2V lithium-ion
2 Full Charge Voltage 25.2V
3 Continuous Discharge Current 20A
4 Overcharge Protection Voltage ~4.25V – 4.3V per cell
5 Over-discharge Protection Voltage ~2.5V – 3.0V per cell
6 Equalization Function Yes
7 Connection Type Solder pads (spot welding supported)
8 Module Dimensions Compact PCB for 6S packs

Usage

Getting Started

  1. Identify the battery pack terminals — Locate the positive (+), negative (-), and mid-point (BM1 through BM5) terminals of your 6S battery pack.

  2. Connect the battery — Solder or spot weld the B+ pad to the pack positive terminal, B- pad to the pack negative terminal, and BM1 through BM5 to the respective mid-points between the six cells.

  3. Connect the output — Solder your load or output wires to the P+ and P- pads on the protection board.

  4. Test the protection — Verify that the output voltage is present when the pack is within safe limits, and that the output disconnects when any cell voltage drops too low or rises too high.

  5. For high-current applications — Ensure all wiring and connections are rated for the maximum current your application will draw. Use appropriately sized wires and connectors.

Protection Thresholds (Typical)

Parameter Threshold Action
Overcharge ~4.25V – 4.3V per cell Disconnect charger
Over-discharge ~2.5V – 3.0V per cell Disconnect load
Overcurrent 20A Disconnect output

Connection Points

Pad Function
B+ Battery pack positive terminal
B- Battery pack negative terminal
BM1 First mid-point between cells
BM2 Second mid-point between cells
BM3 Third mid-point between cells
BM4 Fourth mid-point between cells
BM5 Fifth mid-point between cells
P+ Protected output positive
P- Protected output negative

Typical Applications

  • Power tools — High-current protection for drills, saws, and other tools

  • Solar lighting systems — Reliable power for solar street lights and garden lights

  • E-bikes — High-power protection for electric bicycles

  • Energy storage systems — Protect 6S battery packs in solar storage

  • Portable power stations — High-current protection for portable power

  • Electric scooters — Safe power for personal mobility devices

  • Educational projects — Teaching battery safety and protection principles

Notes for Business Buyers

  • High-current capability — 20A rating fills the gap between standard 6S boards and higher-current BMS systems.

  • Equalization function included — Ensures even charge and discharge for longer pack life.

  • Integrated BMS design — Compact, self-contained protection solution.

  • Suitable for bulk purchasing — Ideal for battery pack assemblers, power tool manufacturers, and solar lighting manufacturers.

Q: What is the 6S 24V 20A BMS used for?

It is a safety module that protects 6-cell lithium battery packs from overcharge, over-discharge, and overcurrent conditions, with an equalization function for even charging.

Q: What batteries are compatible with this BMS?

It is designed for 6S (6-cell) 22.2V lithium-ion battery packs with a full charge voltage of 25.2V. This is commonly referred to as a 24V system.

Q: What is the continuous discharge current?

The BMS is rated for 20A continuous discharge. Ensure all wiring and connections are rated for your application’s current draw.

Q: What are the protection thresholds?

Overcharge protection activates at approximately 4.25V–4.3V per cell. Over-discharge protection activates at approximately 2.5V–3.0V per cell. Overcurrent protection activates at 20A.

Q: What is the equalization function?

The equalization function monitors each cell during charging and bleeds off excess charge from cells that reach full voltage before others, ensuring all cells reach the same voltage.

Q: What is the difference between B+/-, BM1–BM5, and P+/-?

B+ and B- connect to the pack positive and negative terminals. BM1 through BM5 connect to the mid-points between the six cells. P+ and P- provide the protected output to your load or charger.

Q: Can I spot weld this BMS to the battery?

Yes. The board supports both direct soldering and spot welding. The exposed pads are compatible with spot-welded nickel strips.

Q: Can I use this BMS with a 5S or 7S battery pack?

No. This BMS is specifically designed for 6S (6-cell) 24V battery packs. For other configurations, a different protection board or BMS is required.

Q: Does the BMS protect against short circuits?

Yes. The BMS includes overcurrent protection that disconnects the output if a short circuit or excessive current is detected.

Q: Can I purchase in bulk for a product development project?

Yes. This BMS is suitable for both individual users and business purchasing, including battery pack assemblers, power tool manufacturers, and solar lighting manufacturers.