SB003 Super Light Battery – SL8 Battery Incident – 21 Nov 2022 Follow-Up

Date Released: November 21st, 2022

Subject: SL8 Battery Incident – investigation closure

Effectivity: Immediate

Required Action:  None at this time – Alert

INTRODUCTION

This is the final follow-up to our 14 Nov Service Bulletin regarding an SL8 battery fire at our East Coast office. After a comprehensive investigation of the incident, we cannot conclusively determine the root cause of the battery fire and have reached the area of diminishing returns on our fault tree and investigation actions. Therefore, we are concluding the investigation of this incident.  Below we describe some of our findings.  

There are no required actions and customers are advised to continue normal SL4 / SL8 / Astro operations with diligent attention paid to any battery faults. Freefly continues to be confident in our SL batteries and stands behind their safety, reliability, and performance. 

DISCUSSION

Since our previous bulletin, we have focused primarily on two possibilities: overvoltage leading to critical component failure, and manufacturing defects in the PBCA.  Here is the status of investigation on each possible failure mechanism:

• Overvoltage incident
  • In extreme testing, we have not been able to generate a single overvoltage event large enough to cause this failure.  
• Manufacturing error or defect in a PCBA
  • No systemic process errors or omissions have been identified.  We are still awaiting some records from our supplier.  If those uncover any anomalies, we will send another update with those findings.

In addition to the two specific branches of our fault tree listed above, we investigated internal engineering and manufacturing records and searched technical papers from universities, manufacturers and professional organizations.  We found nothing that would allow us to make a definitive statement about the root cause of this incident.

RECOMMENDATION

There is no immediate action required from our customers.  If you have any abnormal battery behavior during use, charging, or storage, please contact Freefly Support. 

Freefly is closing this  incident investigation.  If any new information becomes available, we will follow up with all SL8 / SL4 / Astro customers.  

For Service Information Contact Freefly Support: Support@freeflysystems.com https://freeflysystems.com/support