1. Product Overview
This manual provides essential information for the safe and effective use of your new FLYORZO BL-21CI replacement battery. Please read it carefully before installation and use.

Figure 1: FLYORZO BL-21CI Replacement Battery
2. Safety Information
WARNINGS:
- Use specified Itel charger only.
- May explode if disposed of in fire.
- Keep the battery out of reach of children.
- Do not short-circuit the battery. Accidental short-circuiting can occur when a metallic object such as a coin, clip, or pen causes direct connection of the positive (+) and negative (-) terminals. Short-circuiting the terminals may damage the battery or the connecting object.
- Do not squeeze or subject to strong mechanical shocks.
- Do not disassemble or change the structure of the battery.
- Avoid exposing the battery to liquid.
- Avoid exposing to high temperatures (above 140°F / 60°C).
- Do not remove the battery label.
CAUTION:
- Please stop charging when the battery is 100% charged to avoid overcharge.
- Keep the battery power between 5%-95% for optimal longevity.
3. Setup and Installation
Before installing the new battery, ensure your phone is powered off and disconnected from any charging source.
- Carefully remove the back cover of your Itel A33, W5001, or W5001P cell phone.
- Locate the existing battery. If present, gently lift and remove it from its compartment.
- Insert the new FLYORZO BL-21CI battery into the battery compartment, ensuring the contacts align correctly with the phone's terminals.
- Press down gently to ensure the battery is securely seated.
- Replace the back cover of your phone.
- Power on your phone.
If your phone does not power on, ensure the battery is correctly installed and has some charge. If issues persist, refer to the Troubleshooting section.
4. Operating Instructions
Initial Use and Charging Cycle
For optimal performance and battery longevity, follow these initial charging guidelines:
- When you first receive the battery, use it until it is fully discharged.
- Then, charge it for more than 1-2 hours after it indicates full charge.
- Use it out completely again.
- Repeat this cycle (full discharge, then charge fully for 1-2 hours extra) for 3 times.
- After these initial cycles, you can use and charge the battery normally.
General Usage Tips
- Terminate any applications that are not in use to conserve battery life.
- Switch off vibration, reduce ring tone volume, and shorten screen timeout settings to extend usage time.
- Avoid overcharge and over discharge. Stop charging when the battery is 100% charged.
- Keep the battery power between 5%-95% during regular use for best performance and lifespan.
5. Maintenance and Storage
- Charging: Always use a specified Itel charger. Do not use inferior chargers, as they can damage the battery. Avoid leaving the battery in the charger for excessively long periods after it's fully charged.
- Temperature: Store and operate the battery within a temperature range of 20℃ to 5℃ (68°F to 41°F) for optimal performance. Avoid exposing the battery to high temperatures (above 140°F / 60°C) or extreme cold.
- Physical Care: Protect the battery from liquid exposure, strong mechanical shocks, squeezing, or puncturing.
- Disassembly: Never attempt to disassemble or modify the battery.
- Label Integrity: Do not remove the battery label, as it contains important product information and safety warnings.
6. Troubleshooting
If you encounter issues with your new battery, consider the following:
- Phone not powering on: Double-check that the battery is correctly installed and its contacts are clean and properly aligned with the phone's terminals. Ensure the battery has some charge.
- Temporary low capacity: A new battery or one not used for a long time may initially show a temporary short capacity. This is normal. The total capacity will be reinstated after 3-5 full charge/discharge cycles as described in the "Operating Instructions" section.
- Rapid discharge: Ensure no unnecessary applications are running in the background, and screen brightness/timeout settings are optimized. Avoid using the phone in extreme temperatures.
- Charging issues: Verify that you are using a compatible and functional charger. Ensure the charging port on your phone is clean and undamaged.
If problems persist after following these steps, please contact customer support.
7. Specifications
| Feature | Detail |
|---|---|
| Model Number | BL-21CI |
| Battery Type | Rechargeable Li-ion battery (Polymer battery) |
| Compatible Brand | Itel |
| Compatible Models | Itel A33, W5001, W5001P |
| Rated Voltage | 3.8V |
| Rated Capacity | 2150mAh / 8.17Wh |
| Typical Capacity | 2200mAh / 8.36Wh |
| Limited Charge Voltage | 4.35V |
| Quality Certification | CE |
| Origin | Mainland China |
| Production Date | 20200620 |
8. User Tips
- Battery Conditioning: Remember the initial 3-5 full charge/discharge cycles to condition your new battery for optimal long-term performance.
- Power Saving: Actively manage background apps, screen brightness, and vibration settings on your phone to maximize battery life between charges.
- Smart Charging: Avoid leaving your phone plugged in overnight or for extended periods after it reaches 100% charge. This helps prevent overcharging and prolongs battery health.
- Temperature Awareness: Be mindful of where you leave your phone. Extreme heat (e.g., in a hot car) or cold can significantly degrade battery performance and lifespan.
9. Warranty and Support
This product is designed for reliable performance. If you experience any quality issues or have questions regarding the use, maintenance, or troubleshooting of your FLYORZO BL-21CI replacement battery, please contact the seller or manufacturer's customer support for assistance.
Incorrect use of products may lead to damage to your device. Always refer to this manual and seek professional advice if unsure.