dji TB50 - User Manual

TB50 & TB55 User Guideline (Updated – 19 December 2018)
Background
DJI released a firmware update on 16 November 2018 following reports of a small number of TB50 and TB55
batteries showing incorrect power levels which led to the loss of power mid-flight. The firmware update
addresses a rare issue involving the battery state of charge (SOC) calculation algorithm by incorporating the
following conservative measures listed below which serve to enhance the battery management system and
optimize power supply during flight.
On 19 December 2018, DJI released new firmware updates which serve to address a small number of reports of
Matrice 200 Series drone users experiencing early Return-to-Home (RTH) or Automatic Landing (AL). These
cases were the result of false alarms triggered by the conservative measures DJI implemented in November.
This new firmware update (v01.02.0301) further improves the algorithm accuracy of the battery management
system to enhance user experience without compromising flight safety and product reliability which remain DJI’s
top priorities.
For TB55 batteries used with M200 series drones, the firmware update will impose these new battery
safeguards:
Additional battery heating before take-off (S1)
The additional heating will prevent batteries from turning off unexpectedly at low temperatures. The temperature
of both batteries must now be 16°C (61°F) or higher before the aircraft can take off. This is because a battery
with low temperature has a higher internal resistance, which causes lower voltage than in warmer conditions. A
battery with low voltage will provide a lower level of power to the drone, and hence impose higher risk of a power
loss.
1
Improved battery percentage and fault detection (S2)
The battery percentage check before take-off has been improved, and users will be warned when the battery is
faulty or the remaining battery charge suddenly jumps to a false higher percentage. The voltage of the battery
will be used to verify the SOC value by the further improved DJI algorithm in the new firmware. This SOC value
will be compared to the one calculated by the battery SOC calculation algorithm to determine if there is a “false
high” SOC reading. If there is a “false high” SOC reading, then the aircraft will not be able to take off.
Enhanced Return-to-Home (RTH) or Automatic Landing (S3)
When the DJI algorithm detects a difference in SOC levels (this calculation runs within the battery and is
therefore not visible to users through the screen) between the algorithm and the actual level that is too large,
RTH (Return-to-Home) will be activated at a detected battery level of 30% and Automatic Landing (AL) activated
at 10% (based on the DJI algorithm). Previously observed false alarms, that triggered early RTH or AL in a small
number of cases, have been reduced drastically.
For TB50 batteries used with M200 series drones, the FW update will impose this new battery safeguard:
Additional battery heating before take-off (S1)
The additional heating will prevent batteries from turning off unexpectedly at low temperatures. The temperature
of both batteries must be 16°C (61°F) or higher before the aircraft can take off. This is because a battery with
low temperature has a higher internal resistance, which causes lower voltage than in warmer conditions. A
battery with low voltage will provide a lower level of power to the drone, and hence impose higher risk of a power
loss.
2
1
Flight times vary depending on age of batteries, temperature of the environment, altitude or payload.
2
Flight times vary depending on age of batteries, temperature of the environment, altitude or payload.

Summary

Background

Additional battery heating before take-off (S1)

Prevents unexpected battery shutdown at low temperatures; requires batteries to be 16°C or higher for takeoff.

Improved battery percentage and fault detection (S2)

Enhances battery check before takeoff, warns of faulty batteries or false SOC readings, uses voltage for verification.

Enhanced Return-to-Home (RTH) or Automatic Landing (S3)

Activates RTH at 30% and AL at 10% SOC to mitigate false alarms triggered by conservative measures.

Guideline

Latest firmware update advice

Advises M200 series drone users to update to the latest firmware to minimize disruption to operations.

Inconsistent firmware notification

Warns of potential 'inconsistent firmware' notifications when using TB50 batteries with different firmware versions.

Battery heating time

Explains S1 safeguard causes longer heating time; suggests pre-heating batteries or keeping them at room temperature.

Pilot actions for early RTH or AL

Provides pilot actions to interrupt RTH or steer during AL if early triggers occur due to risk mitigation.

Pre-flight and cold weather battery preparation

Offers tips for pre-flight checks and battery preparation for cold weather environments.

Flight Operations

Cold environment flight considerations

Reminds users that flight times reduce in cold environments and to ensure sufficient battery for RTH.

Battery and environment handling during flight

Advises on handling batteries and aircraft when moving between warm and cold environments to prevent issues.

Smart gloves recommendation

Recommends smart gloves for using smart devices without removing gloves in cold conditions.

Storage

Battery storage temperature limits

Do not store charged packs below 0°C. Store between 10-45°C (50-113°F) to avoid damage or shorten life.

Recommended storage charge level

Keep packs between 50-65% charge. Recharge every 90 days to maintain this level.

Overview

1. Function Description
2. Important Technical Specifications
3. Usage Features
4. Maintenance Features

This document outlines the user guidelines for DJI TB50 and TB55 intelligent flight batteries, specifically addressing firmware updates and operational considerations, particularly in cold weather.

Function Description:

The TB50 and TB55 are intelligent flight batteries designed for DJI drones, including the Matrice 200 series and Inspire 2. Their primary function is to provide power to the aircraft, enabling flight. These batteries incorporate sophisticated battery management systems (BMS) that monitor and manage their state of charge (SOC), temperature, and overall health to ensure safe and reliable operation. Recent firmware updates have focused on enhancing the accuracy of the SOC calculation algorithm and implementing conservative measures to prevent unexpected power loss, especially in challenging environmental conditions.

Important Technical Specifications:

The document highlights several technical aspects related to the batteries' performance and safety:

• Temperature Threshold for Take-off (S1): For TB50 and TB55 batteries used with M200 series drones, the temperature of both batteries must be 16°C (61°F) or higher before the aircraft can take off. This safeguard is implemented because low temperatures increase internal resistance, leading to lower voltage output and a higher risk of power loss.
• Improved Battery Percentage and Fault Detection (S2): The firmware includes an enhanced algorithm that verifies the SOC value against the battery's voltage. If a "false high" SOC reading is detected, indicating a discrepancy between the calculated SOC and the actual voltage, the aircraft will be prevented from taking off. This system also warns users of faulty batteries or sudden jumps in reported charge.
• Enhanced Return-to-Home (RTH) or Automatic Landing (S3): The DJI algorithm, running within the battery, continuously compares calculated SOC levels with actual levels. If a significant difference is detected, RTH will be activated at a detected battery level of 30%, and Automatic Landing (AL) at 10%. This feature aims to prevent unexpected power loss by initiating a safe return or landing before the battery is critically depleted.
• Storage Temperature: Batteries should not be stored at temperatures lower than 0°C. The recommended storage temperature range is between 10°C and 45°C (50°F - 113°F).
• Storage Charge Level: Batteries should always be kept between 50% and 65% charge during storage. For long-term storage (more than a few months), it is recommended to check these levels regularly and recharge to 50-65% every 90 days.

Usage Features:

The guidelines provide extensive advice on how to use the TB50 and TB55 batteries effectively and safely, particularly in cold weather:

• Firmware Updates: Users are strongly advised to update their drone and batteries to the latest firmware to benefit from the latest safety enhancements. It's recommended to allocate extra time for these updates before flights.
• Inconsistent Firmware Notification: If using batteries with different firmware versions (e.g., some updated, some not), users may receive an "inconsistent firmware" notification, which could lock the drone. DJI advises using batteries with the same firmware until a new update is released.
• Pre-flight Battery Heating (S1): Due to the 16°C (61°F) take-off temperature requirement, batteries may take longer to heat up. Pilots are advised to pre-heat batteries or keep them at room temperature before flying outdoors. If the environment is too cold, hovering the aircraft for about 1 minute can help warm the batteries to the required temperature.
• Keeping Batteries Warm: Practical tips for maintaining battery temperature include using hand warmers, warm rice packs (microwave 5-10lb of dry rice in a resealable bag for 5-10 minutes and place in a cooler with batteries), keeping batteries close to the body, and preheating them during travel.
• Full Charge Before Use: Always ensure batteries are fully charged before flight.
• Acclimatization: When moving the aircraft from a warm to a cold environment, allow it to acclimatize without batteries for at least 10-15 minutes.
• Remote Controller Calibration: Moving the remote controller (RC) from warm to cold may cause a calibration error. If this occurs, turn off the aircraft and perform an RC calibration via the RC tab in the app.
• Moisture Management: Bring dry towels to wipe off any moisture that might build up on the aircraft or in the field. Ensure all contacts on cameras and batteries are dry before installation or storage.
• Smart Gloves: Smart gloves are recommended for operating smart devices without removing gloves in cold conditions.
• Responding to Early RTH/AL: In rare cases of early RTH, pilots can interrupt it by pressing "X" on the screen. If AL begins, pilots can still steer the drone with the joystick to find a safe landing spot, and pushing up the throttle can slow or counteract the descent. These responses are part of a risk mitigation strategy, not hardware faults.
• Avoid Partially Discharged Packs: Do not fly with partially discharged packs or those that have entered self-discharge mode.

Maintenance Features:

The document touches upon maintenance primarily through storage recommendations:

• Proper Storage Temperature: Avoid storing charged packs below 0°C or outdoors in cold temperatures, as this can severely damage them and shorten their lifespan. Store batteries between 10°C and 45°C (50°F - 113°F).
• Maintaining Storage Charge Level: Keep batteries between 50% and 65% charge during storage. For extended storage periods (several months), regularly check the charge levels and recharge to 50-65% every 90 days.
• Intelligent Flight Battery Safety Guidelines: Users are directed to the "Intelligent Flight Battery Safety Guidelines" for more detailed information on minimizing operational disruptions, implying that adherence to these guidelines is crucial for battery longevity and performance.

The overall emphasis is on proactive management of battery conditions, especially temperature, and adherence to firmware updates and operational protocols to ensure flight safety and extend battery life.

dji TB50 Specifications

General

Capacity	4280 mAh
Voltage	22.8 V
Battery Type	LiPo 6S
Energy	97.58 Wh
Net Weight	515 g
Operating Temperature	-20°C to 40°C
Max Charging Power	180 W
Compatible Models	Inspire 2, Matrice 200 Series