SPECIFICATIONS

Safe Power Core! 3S 25A 18650 Li-ion BMS Protection Board, Designed for Power Tools E-Bike E-Scooter with Full Overcharge/Discharge/Short Circuit Protection.

Key Features & Benefits:

3S Specific Design: Optimized for 3-cell series Li-ion packs (11.1V nominal, 12.6V charge). Precisely calibrated voltage thresholds, plug-and-play.

25A Continuous, 50A Peak: Handles up to 25A continuous charge/discharge, with 40-50A peak surge current for high-demand applications like power tools and e-bike start-up.

Comprehensive Safety Protections: Integrated protection against over-charge (~4.25V/cell), over-discharge (~2.80V/cell), over-current, short circuit, and temperature. Ensures safety and extends cycle life.

Wide Chemistry Compatibility: Works with common 3.6V/3.7V NMC, INR 18650 cells. A reliable choice for building or repairing battery packs.

Simple to Use: Clearly labeled pads (B-, B1, B2, B+, P-, P+) for straightforward wiring, easy integration into DIY projects or finished products.
Product Description: Equip your 3S lithium battery project with a professional "safety guardian". This BMS is built for high-power applications. It's not just a connector but the key to ensuring your valuable battery pack operates safely, stably, and durably. Whether you're modifying power tool batteries, assembling a spare e-bike pack, or building a portable power station, it provides robust protection for peace of mind.

🚨 Important Notes Before Buying!
❌ 【Product Clarification & Limits】: This is a protection board, NOT a charger or a finished battery pack! It requires your soldering to a pre-series-connected 3x 18650 battery pack. NOT compatible with 4S or other series configurations. Incorrect connection will damage it!
⚠️ 【Most Common Mistakes & Safety Warnings】

Voltage MUST Match: For 3S (3-Cell Series) Li-ion batteries ONLY (~12.6V total). Do not use with 1S, 2S, 4S packs or lead-acid batteries!

Wiring Sequence is CRITICAL: Must solder to battery pack in order: B- → B1 → B2 → B+. NEVER skip or reverse connections!

Power Wire Requirement: For high-current applications (e.g., e-bikes), wires to P- and P+ must be sufficiently thick (recommended ≥12AWG).
✅ 【Required Conditions & Skills】

Required Materials: Pre-welded/soldered 3x 18650 battery pack, high-power wires, soldering iron (and skill).

Required Knowledge: Ability to identify battery polarity, understand series connections, basic soldering skill.

Testing Advice: After assembly, test output voltage and polarity with a multimeter before connecting to load or charger.
🔧 【Difference from TP4056 etc.】: This is a BMS (Battery Management System) for multi-cell packs. The TP4056 is a single-cell Li-ion charging module. They have different functions and applications. Do not confuse them.

Specifications:

Designed For: 3S (3-Cell Series) Li-ion Battery Packs

Battery Chemistry: NMC, INR (3.6V/3.7V per cell)

Nominal Voltage: 11.1V

Charge Voltage: 12.6V

Continuous Current: 25A (Charge & Discharge)

Peak Current: 40A - 50A (short duration)

Over-Charge Protect Voltage: Approx. 4.25V ±0.03V per cell

Over-Charge Recovery Voltage: Approx. 4.10V ±0.05V per cell

Over-Discharge Protect Voltage: Approx. 2.80V ±0.05V per cell

Over-Discharge Recovery Voltage: Approx. 3.00V ±0.10V per cell

Protections: Over-Charge, Over-Discharge, Over-Current, Short Circuit, Temperature

Temperature Protection: Supported (NTC thermistor required)

Dimensions: Approx. 50 x 35 x 4 mm (actual product may vary)
Package Includes:

1 x 3S 25A Li-ion BMS Protection Board

Note: Wires and cables are included ONLY in the "with Wires" combo SKU. They are NOT included in the single board SKU. Please select your SKU carefully.