Introduction
This manual provides detailed instructions for the Dlyfull Multi-Battery Tester Set, which includes models B1L, B2, B3, B4, and DB1. Each tester is designed to accurately assess the health and performance of various battery types, offering reliable information for your power needs. Please read this manual thoroughly before operating any of the devices.

Figure 1: Overview of the Dlyfull Multi-Battery Tester Set.
General Setup and Safety Precautions
Before using any of the Dlyfull battery testers, ensure you understand the basic setup and safety guidelines.
Safety Precautions:
- Always handle batteries with care. Do not short-circuit battery terminals.
- Do not attempt to test damaged or leaking batteries.
- Ensure correct polarity when inserting batteries into the testers.
- Keep testers away from water and extreme temperatures.
- Store testers in a dry, cool place when not in use.
Initial Setup:
- For testers requiring internal power (e.g., B4), insert the specified AAA alkaline batteries.
- For rechargeable testers (e.g., DB1), ensure the device is fully charged via the provided USB-C cable before first use.
Operating Instructions
1. Dlyfull DB1 Battery Tester
The DB1 is a versatile tester compatible with 1.2V Ni-MH/CD, 1.5V Alkaline, 3.0V Lithium, 3.7V Li-ion, and 9V batteries. It features a smart LCD display and a magnetic battery slot for secure testing.
- Battery Compatibility: Supports various sizes including 1.2V Ni-MH/CD, 1.5V Alkaline, 3.0V Lithium, 3.7V Li-ion, and 9V batteries.
- Operation: Insert the battery into the magnetic slot, ensuring correct polarity. The smart LCD will automatically display accurate voltage and health status. Use the V-SELECT button for one-touch operation to cycle through display modes or battery types if applicable.
- Recharging: The DB1 is rechargeable via USB-C and provides up to 15 hours of use per charge. Connect the included USB-C cable to a power source to charge.

Figure 2: Dlyfull DB1 Tester with battery compatibility and LCD display.

Figure 3: DB1's magnetic battery slot and USB-C charging capability.
2. Dlyfull B2 Battery Tester
The B2 is a compact and lightweight tester for common household batteries. It provides quick health checks with a clear LCD display.
- Battery Compatibility: Designed for AA, AAA, C, D, 9V, CR123A, CR2, CRV3, 2CR5, CR-P2, N, and various button cells. Note: This tester is not designed for rechargeable batteries.
- Operation: Simply insert the battery into the appropriate slot or connect the terminals. The LCD display will show the battery status as 'Poor', 'Weak', or 'Good'.
- Features: Lightweight, pocket-friendly, with an anti-slip grip.

Figure 4: Dlyfull B2 Tester with supported battery types and LCD status indicators.

Figure 5: Examples of testing different battery types with the B2 tester.
3. Dlyfull B3 Battery Tester
The B3 is a multi-functional tester providing detailed information including capacity, voltage, and internal resistance, suitable for a wide range of batteries.
- Battery Compatibility: Covers A, AA, AAA, AAAA, C, SC, D, 9V, 3.7V Li-ion (e.g., 26650, 21700, 18650), and various button cells.
- Operation: Select the appropriate voltage setting. Connect the leads (red to positive, black to negative) to the battery terminals. The large LCD screen will display battery power, capacity, voltage, and internal resistance.
- Features: Helps prevent overcharging by accurately detecting battery parameters. Compact and easy to use.

Figure 6: Dlyfull B3 Tester's comprehensive compatibility and LCD display.

Figure 7: High-quality test pins of the B3 tester for accurate measurements.
4. Dlyfull B4 Battery Tester
The B4 offers broad compatibility and displays battery voltage and level as a percentage and bar, making it easy to understand battery status.
- Battery Compatibility: Supports 12 types, including 1.2V Ni-MH, 1.5V Alkaline, 3.7V Li-ion, 9V, and 12V, plus AAA, AA, C, D, N, CR123A, and button cells.
- Operation: For cylindrical batteries, use the black pin to connect. For button cells, place them in the designated slots. The LCD displays voltage and battery level as a percentage and a bar graph.
- Self-Check: Features a self-check button to quickly verify the tester's internal battery status.
- Power: Requires 1.5V AAA Alkaline batteries for operation.

Figure 8: Dlyfull B4 Tester's wide compatibility and clear LCD interface.
5. Dlyfull B1L Battery Tester
The B1L is a compact and portable tester for common alkaline and button-cell batteries, providing quick and accurate results with an intuitive display.
- Battery Compatibility: For 1.5V AAA, AA, C, D alkaline, 9V, and button-cell batteries.
- Operation: Simply align the battery's terminals with the tester's contacts. The intuitive display will show 'Good' (green), 'Low' (yellow), or 'Replace' (red) for easy battery status reading.
- Portability: Lightweight at just 70g, making it easy to carry and store.

Figure 9: Dlyfull B1L Tester in use, demonstrating its compact size.
Maintenance
Proper maintenance ensures the longevity and accuracy of your Dlyfull battery testers.
- Cleaning: Use a soft, dry cloth to clean the exterior of the testers. Do not use abrasive cleaners or solvents.
- Storage: Store the testers in a cool, dry place, away from direct sunlight and extreme temperatures.
- Battery Replacement (for B4): If the B4 tester's display becomes dim or inaccurate, replace its internal 1.5V AAA alkaline batteries.
- Charging (for DB1): Regularly charge the DB1 tester to maintain its internal battery health, especially if not used for extended periods.
Troubleshooting
If you encounter issues with your Dlyfull battery testers, refer to the following common troubleshooting steps:
| Problem | Possible Cause | Solution |
|---|---|---|
| Tester does not power on (B4) | Dead or incorrectly inserted internal AAA batteries. | Replace AAA batteries, ensuring correct polarity. |
| Tester does not power on (DB1) | Internal battery is depleted. | Charge the DB1 via USB-C cable. |
| Inaccurate readings | Poor contact with battery terminals; incorrect battery type selected (B3); dirty contacts. | Ensure firm contact. Verify battery type selection. Clean contacts with a dry cloth. |
| Display is dim or flickering | Low internal battery (B4, DB1). | Replace AAA batteries (B4) or recharge (DB1). |
| B2 shows "Poor" for new battery | Battery is genuinely low; B2 is not for rechargeable batteries. | Try a different new battery. Ensure you are not testing a rechargeable battery with B2. |
If the problem persists after trying these steps, please contact Dlyfull customer support for further assistance.
Specifications
Below are the general specifications for each Dlyfull battery tester in this set:
Dlyfull DB1:
- Compatible Battery Types: 1.2V Ni-MH/CD, 1.5V Alkaline, 3.0V Lithium, 3.7V Li-ion, 9V.
- Display: Smart LCD.
- Power Source: Rechargeable via USB-C.
- Battery Life: Up to 15 hours per charge.
- Features: Magnetic battery slot, V-SELECT button.
Dlyfull B2:
- Compatible Battery Types: AA, AAA, C, D, 9V, CR123A, CR2, CRV3, 2CR5, CR-P2, N, button cells. (Not for rechargeable batteries).
- Display: LCD (Poor, Weak, Good).
- Features: Compact, lightweight, anti-slip grip.
Dlyfull B3:
- Compatible Battery Types: A, AA, AAA, AAAA, C, SC, D, 9V, 3.7V Li-ion (26650, 21700, 18650, etc.), button cells.
- Display: Large LCD (Capacity, Voltage, Internal Resistance).
- Features: Test leads included, accurate detection.
Dlyfull B4:
- Compatible Battery Types: 1.2V Ni-MH, 1.5V Alkaline, 3.7V Li-ion, 9V, 12V, AAA, AA, C, D, N, CR123A, button cells.
- Display: LCD (Voltage, Percentage, Bar).
- Power Source: 1.5V AAA Alkaline batteries (not included).
- Features: Black pin for cylindrical, slots for button cells, self-check button.
Dlyfull B1L:
- Compatible Battery Types: 1.5V AAA, AA, C, D alkaline, 9V, button-cell batteries.
- Display: Intuitive (Good, Low, Replace).
- Weight: Approximately 70g.
- Features: Compact and portable.
Warranty and Support
Dlyfull products are designed for reliability and performance. For warranty information and customer support, please refer to the contact details provided with your purchase or visit the official Dlyfull website.
Website: Dlyfull Official Store on Amazon
Please retain your proof of purchase for warranty claims.




