EF-004
12S–18S 250A Smart Drone BMS for semi-solid UAV packs(44.8V–66.6V)
Dual-pack parallel, customizable protocols. From reconnaissance drone to fire monitoring drones.
Designed for inspection and monitoring
UAV applications
UAV applications
Aerial photography, crop monitoring, mapping, pipeline inspection,wildfire monitoring, environmental monitoring, infrastructure inspection and construction progress monitoring.
Product Introduction
The EF-004 is a configurable smart BMS designed for inspection,
monitoring and surveying UAV battery packs.
It supports 12S–18S LiPo and semi-solid-state battery configurations,
with isolated CAN, RS485 and DroneCAN communication options. The BMS
can also be configured for dual-pack parallel operation, allowing it
to support UAV platforms that require extended flight time and stable
high-current performance.
Protection thresholds, communication parameters and interface options
can be configured to suit the battery pack, flight-control system and
charger requirements.
Protocol integration is available for selected PX4, DroneCAN, SkyRC CAN
and project-specific UAV systems. Compatibility should be confirmed
during the engineering evaluation stage.
Compatibility should be confirmed during the engineering evaluation stage.
Key Specifications
| Series configuration | 12S-18S | Isolated RS485 | Standard |
| Continuous Discharge | 250A | TYPE-C Communication | Standard |
| Continuous Charge Current | 120A | Isolated CAN interface | Standard |
| NTC Temp Sensing | 4 ch + 1 MOS | Battery heating | |
| Passive Balancing | Bluetooth Module | ||
| External switch input | Parallel-pack support | ||
| Charge-current limiting | Configurable | LCD Display | Optional |
| Secondary Protection | LED Indicator | ||
| Pre-Discharge | RTC Function |
Compatible Battery Models
Ayaa BMS compatible high-performance lithium and semi-solid-state UAV battery configurations.
| 18S BMS - Verified Compatible Battery Packs |
|---|
|
High Voltage Semi-Solid 18S1P 71.1V 67000mAh UAV Battery
High Voltage Semi-Solid 18S1P 66.6V 30000mAh UAV Battery
18S 47000mAh 68.4V UAV Battery
High Voltage Semi-Solid 18S1P 66.6V 45000mAh UAV Battery
High Voltage Semi-Solid 18S1P 66.6V 35000mAh UAV Battery
High Voltage Semi-Solid 18S1P 66.6V 31000mAh UAV Battery
High Voltage Semi-Solid 18S1P 71.1V 31000mAh UAV Battery
High Voltage Semi-Solid 18S1P 71.1V 55000mAh UAV Battery
|
Engineering Capabilities
High-Current UAV Applications
Designed for UAV battery packs with demanding discharge profiles. Continuous and peak-current ratings are specified according to the selected hardware configuration.
Configurable Protection Strategy
Configurable monitoring and protection thresholds for cell voltage, pack current and temperature conditions.
Communication Integration
Supports isolated CAN, isolated RS485 and DroneCAN integration, with project-specific protocol configuration available.
OEM / ODM Engineering Support
Customisation support for series configuration, interfaces, firmware parameters, charger communication and battery-pack integration.
Technical FAQ and Troubleshooting
Q: What should I do if I notice smoke or a burning smell when connecting the voltage-sensing harness?
Q: Battery pack does not discharge — what to check?
Q: Why does the voltage-sensing harness become warm during operation?
Q: One cell voltage drifts significantly under load — how to resolve?
Q: Why does the load disconnect unexpectedly?
1) Battery voltage dropped below the over-discharge threshold;
2) Load/inverter power exceeded over-current limits;
3) Device has large capacitors that triggered short-circuit protection. Connect to PC software or Bluetooth app to read the active fault code.
Q: Power cuts out during rapid ascent — what should I check?
Industry Experience
Clients Served
Countries Covered
Technical Specifications
12S-18S Semi-Solid LiPo Drone BMS - Engineering Data Sheet
General Specifications
| Parameter | Specification | Parameter | Specification |
| Battery Pack Configuration | 12S-18S Semi-Solid LiPo | Communication Interface | CAN (1M, ID:1) + TYPE-C + BLE |
| Interface Type | Charge/Discharge Shared Port | Operating Power | ≤30mA |
| Charging Voltage | 4.35V × Number of Strings | Sleep Power | ≤2mA |
| Cell Voltage Range | 3.3V-4.35V | Deep Sleep Power | ≤100μA |
| Continuous Charge Current | 120A | Sleep Conditions | No current, no communication |
| Continuous Discharge Current | 250A | Deep Sleep Conditions | Cell under-voltage state |
| Operating Temperature | -30°C - 70°C | Dimensions | 180 × 90 × 15mm |
Total Voltage Protection Parameters
| Protection Type | Parameter | MIN | TYP | MAX | Unit |
|---|---|---|---|---|---|
| Overcharge Protection | Overcharge Voltage | 78.51 | 78.66 | 78.81 | V |
| Protection Delay | - | 1000 | 2000 | mS | |
| Release Voltage | 77.94 | 78.30 | 78.66 | V | |
| Overdischarge Protection | Overdischarge Voltage | 59.20 | 59.40 | 59.60 | V |
| Protection Delay | - | 1000 | 2000 | mS | |
| Release Voltage | 62.64 | 63.00 | 63.36 | V |
Heating Management Parameters
| Parameter | Specification |
|---|---|
| Heating Activation Temperature | 0°C |
| Heating Deactivation Temperature | 10°C |
| Heating Current | 10A |
| Heating Source | Charge circuit |
PC & MOBILE SOFTWARE
AYAA software tool is developed by our company for our intelligent protection board series. The user interface allows the user to perform various operations such as monitoring battery data, modifying BMS parameters and many other functions. The UI is divided into four sections, which are, Battery information, parameter setting, calibration and others.
Key Features
Engineered for reliability, safety, and high-performance UAV operations
Multi-point Temperature Monitoring
Supports multiple NTC sensors per cell group for precise thermal tracking and enhanced safety management.
Isolated RS485 Communication
Communicates via isolated RS485 (Modbus), with adjustable baud rate and configurable device ID (0-255).
Multiple Communication Interfaces
Supports CAN and UART with isolation and communication wake-up for stable data transmission.
Bluetooth Connectivity (Optional)
Enables wireless monitoring via mobile app for real-time battery status and diagnostics.
Flexible Interface & Display
Includes Type-C, SOC display, LED indicators, and customizable display logic for different applications.
Configurable In-Flight Protection Strategy
Supports staged warnings and configurable protection responses for
selected fault conditions, helping the UAV system manage abnormal
battery states more safely during flight.
Self-Discharge & Storage Mode
Supports automatic storage mode with configurable idle time to extend battery lifespan.
Full Fault Reporting
Real-time fault data, diagnostics, and system status transmitted directly to UAV systems.
Applications
Powering a wide range of UAV and aerial system applications
Infrastructure Inspection UAVs
Reliable battery management for drones used in bridge, tower, power-line and industrial facility inspections.
Pipeline Inspection Drones
Stable high-current power support for long-range pipeline, oil and gas infrastructure inspection missions.
Surveying and Mapping UAVs
Smart BMS solutions for surveying, mapping and photogrammetry drones requiring stable flight time and accurate battery data.
Environmental Monitoring Drones
Battery monitoring and protection for UAVs used in environmental surveys, forestry monitoring and remote-area operations.
Fire Monitoring UAVs
Configurable UAV battery protection for wildfire detection, emergency monitoring and high-temperature operating environments.
Security and Surveillance Drones
Reliable battery telemetry and protection for surveillance, reconnaissance and perimeter-monitoring UAV platforms.
Request a Technical Proposal
Tell us about your UAV battery system requirements. Our engineering team will review your application and recommend a suitable BMS configuration.
Prediction. Warning. Stabilization.
- 250A continuous discharge current
- Configurable monitoring and multi-layer protection
- Dual-pack parallel operation support
- Configurable DroneCAN, CAN, RS485 and UART integration
Request Technical Proposal
UAV Power Engineers respond within 12 hours