Introduction
This manual provides detailed instructions for the installation, operation, and maintenance of the Daly LiFePO4 BMS (Battery Management System) for 4-series 12V LiFePO4 battery packs. This BMS is designed to protect your battery pack from various electrical issues, ensuring its longevity and safe operation.
The Daly DL4S BMS is suitable for 4S 12V 14.6V LiFePO4 battery packs, including common capacities such as 50Ah, 100Ah, 200Ah, 280Ah, and 500Ah, often used in solar systems and other applications.
The Daly BMS is designed for a wide range of applications, including electric scooters, e-bikes, tourist vehicles, electric tricycles, low-speed EVs, emergency UPS, solar street lights, and RV & home energy storage systems.
Key Features
- Comprehensive Protection: Includes over charge protection, over discharge protection, over current protection, short-circuit protection, and temperature protection.
- High Quality Components: Manufactured with top-quality (A-level) protective integrated circuit ICs from Seiko of Japan and high voltage resistance, low inner resistance power MOSFETs.
- Efficient Heat Dissipation: Features a heat sink and, for higher current models, an active fan for effective cooling.
- Cell Balancing: Integrated IC with power balancing function ensures each cell is maintained optimally.
- Robust Design: PCB uses high anti-corrosion, high water resistance, high impedance ESD conformal coating.
- Waterproof and Durable: Full sealed, waterproof, dustproof, and shockproof design (Patent No: ZL 2018 2 1243978.5).
- Low Power Consumption: The entire device consumes less than 50uA.
The Daly BMS features a fully sealed, waterproof, dustproof, and shockproof design, protected by patent ZL 2018 2 1243978.5.
Higher current models of the Daly BMS incorporate an active heat dissipation fan to maintain optimal operating temperatures.
The BMS utilizes pure copper for critical connections, ensuring good conductivity and reduced heat generation.
Setup and Installation
Proper installation is crucial for the safe and effective operation of your Daly LiFePO4 BMS. Please follow these steps carefully.
Wiring Diagram for Common Port
Detailed wiring diagram for connecting the Daly BMS to a 4S LiFePO4 battery pack, charger, and motor/load.
Installation Steps:
- Initial Connection Precaution: Do NOT insert the balance wires into the BMS before connecting them to the battery cells. Ensure all battery connections are correct first.
- Connecting Balance Wires:
- Start with the thin black balance wire (B-).
- Connect the second wire (thin red wire) to the positive pole of the first battery cell.
- Continue connecting each subsequent thin wire to the positive pole of each cell in ascending order (e.g., 3rd wire to 2nd cell positive, and so on) until the last cell's positive pole (B+).
- Voltage Verification (Crucial Step):
- Before inserting the balance connector into the BMS, measure the voltage between two adjacent metal terminals on the back of the connector using a multimeter.
- For LiFePO4 batteries, the voltage between adjacent terminals should be between 2.0V and 3.6V. (For Li-ion, 3.0V-4.2V; for LTO, 1.5V-2.75V).
- If the voltages are correct, proceed to insert the connector into the BMS.
- BMS Functionality Check:
- Adjust your multimeter to the buzzer position (continuity test).
- Measure the internal resistance between the B- and P- terminals of the BMS.
- If the internal resistance is 0 (multimeter beeps), the BMS is functioning correctly. If not, do not proceed with welding and contact customer support.
- Main Negative Connection: The final step is to connect the thick blue wire (B-) to the total negative pole of the battery pack.
Post-Wiring Verification:
After all wiring is complete, measure the following voltages:
- Voltage between B+ and B- (total battery pack voltage).
- Voltage between B+ and P- (output voltage from BMS).
These two voltage readings should be equal. If they are, your BMS is working normally and ready for use. If not, recheck your wiring sequence carefully.
The balance cable features a convenient buckle with a reverse snap mechanism to ensure a tight and secure connection, preventing accidental disconnections.
The wires provided are designed to be safe and reliable, featuring strong flame retardancy and good flexibility for wiring at various angles.
The BMS includes reasonable screw positioning holes for easy and secure installation. Dimensions for a 100A model are shown as an example.
Operation
Once installed and verified, the Daly LiFePO4 BMS operates automatically to manage and protect your battery pack. It continuously monitors cell voltages, current, and temperature.
- Overcharge Protection: The BMS will stop charging if any cell voltage exceeds the over charge detect voltage (3.75V ± 0.05V). Charging will resume when the voltage drops to the release voltage (3.55V ± 0.05V).
- Over-discharge Protection: The BMS will cut off discharge if any cell voltage drops below the over discharge detect voltage (2.2V ± 0.1V). Discharge will resume when the voltage rises to the release voltage (2.3V ± 0.1V).
- Overcurrent Protection: If the discharge current exceeds the specified limit, the BMS will activate overcurrent protection.
- Short-circuit Protection: In case of an external short circuit, the BMS will immediately cut off the circuit to prevent damage.
- Temperature Protection: The BMS monitors the temperature during both charging and discharging to prevent operation outside safe temperature ranges (-20°C to 70°C working, -40°C to 80°C storage).
- Balance Function: The integrated balance function helps equalize the voltage across all cells, extending battery life. Balancing activates when cell voltage reaches 3.5V.
Maintenance
The Daly LiFePO4 BMS is designed for low maintenance. However, periodic checks can help ensure optimal performance and longevity.
- Visual Inspection: Periodically inspect the BMS and all wiring for any signs of damage, corrosion, or loose connections.
- Cleanliness: Keep the BMS clean and free from dust and debris. For models with active cooling fans, ensure the fan vents are not obstructed.
- Environmental Conditions: Ensure the BMS operates within its specified working temperature range (-20°C to 70°C) and is stored within its storage temperature range (-40°C to 80°C).
- Waterproof Integrity: While the BMS is waterproof, avoid prolonged submersion or exposure to harsh chemicals.
Troubleshooting
If you encounter issues with your battery pack or BMS, refer to the following common troubleshooting steps:
- BMS Not Activating / No Output Voltage:
- Recheck all wiring connections, especially the balance wires and main power cables (B- and P-). Refer to the "Setup and Installation" section.
- Verify cell voltages. If any cell is significantly over-discharged or overcharged, the BMS may remain in a protected state.
- Ensure the total battery pack voltage is within the operational range.
- Perform the BMS functionality check (internal resistance between B- and P-) as described in the installation steps.
- Battery Pack Not Charging:
- Check the charger connection and ensure it is functioning correctly.
- Verify that no cells are in an overcharge protection state.
- Check for any temperature protection activation.
- Battery Pack Not Discharging / Low Power Output:
- Check the load connection.
- Verify that no cells are in an over-discharge protection state.
- Check for overcurrent or short-circuit protection activation. Reduce the load if it exceeds the BMS's continuous discharge current rating.
- Check for any temperature protection activation.
- Unbalanced Cell Voltages:
- The BMS has an automatic balance function. Allow time for it to balance the cells.
- If significant imbalance persists, ensure all balance wires are securely connected and not damaged.
If troubleshooting steps do not resolve the issue, please contact customer support for further assistance.
Specifications
The Daly LiFePO4 BMS is available in various current ratings. The following table provides general specifications for the 4S LiFePO4 models.
Detailed product parameters for Daly 4S LiFePO4 BMS models, covering discharge, charge, protection, balance, and temperature specifications.
| Function | Description | Specification (LiFePO4 4S) | Unit |
|---|---|---|---|
| Discharge | Continue discharge current | 15-500 | A |
| Sparkle current | 50-600 | A | |
| Charge | Charge current | 8-200 | A |
| Continue discharge current | 120-1200 | A | |
| Inner Resistance | Main Circuit Conduct Inner | ≤20 | mΩ |
| Over charge protection | Over charge detect voltage | 3.75±0.05 | V |
| Over charge release voltage | 3.55±0.05 | V | |
| Balance | Balance detect voltage | 3.5 | V |
| Balance release voltage | 3.5 | V | |
| Balance current | 30±5 | mA | |
| Over discharge protection | Over discharge detect voltage | 2.2±0.1 | V |
| Over discharge delay | 1 | S | |
| Over discharge release voltage | 2.3±0.1 | V | |
| Over current | Over current detect voltage | 1 | V |
| Over current detect delay | Offload | ||
| Short Circuit protection | Short Circuit protection condition | Short circuit of external load | |
| Short Circuit detect delay | 250 | uS | |
| Short Circuit protection release | Offload | ||
| Temp protect | Temp Protect | / | °C |
| Self consumption | Working current | 80A (including 80A) and above 500uA | mA |
| Sleeping current (when in discharge) | 0 | uA | |
| Working Temp | Temp range | -20~70 | °C |
| Storage Temp | Temp range | -40~80 | °C |
Physical Dimensions (Examples):
Examples of different Daly BMS current ratings with their corresponding dimensions.
- 15A/20A: 34*59*9mm
- 30A/40A: 48*75*9mm
- 50A/60A: 61*80*16mm
- 80A: 66*150*19mm
- 100A: 65*166*24mm
- 120A/150A: 95*212*20mm
- 200A/250A: 130*221*32mm
- 300A/400A/500A: 130*257*52mm
Certifications: CE, FCC, RoHS, PSE, ISO.
The Daly BMS has obtained various standard certifications, including CE, FCC, RoHS, PSE, and ISO, ensuring product quality and safety.
User Tips
- Bluetooth Communication: While this manual focuses on the standard 4S BMS, some Daly BMS models offer Bluetooth communication for advanced monitoring. If you require this feature, ensure you purchase a model specifically designed with Bluetooth capabilities.
- Voltage Compatibility: Always double-check that the BMS matches your battery pack's series configuration (e.g., 4S for 12V LiFePO4) and chemistry (LiFePO4).
- Professional Installation: If you are unsure about any wiring steps, it is highly recommended to seek assistance from a qualified professional to avoid damage to the BMS or battery pack.
Warranty and Support
For warranty information, technical support, or any questions not covered in this manual, please contact the seller or manufacturer directly. Refer to your purchase documentation for specific contact details.
If you have any questions regarding the wiring or operation, please contact our customer service for support.
