The ground-breaking method adopted by Morgan Advanced Materials has paved the way for the development of a new solution to defeat the problems caused by the transportation of lithium-based batteries on passenger aircraft.
These batteries are subject to the issue of thermal runaway and several serious incidents have happened in the past, which has caused the international aviation authorities to take strong measures to improve the safety surrounding their transportation as cargo. However, these batteries are still carried by many passengers, and with their tendency to overheat, they pose a constant hazard.
A safe and dependable solution has now been found. It was tested in partnership with a leading airline. The solution harnessed the next generation materials technology from Morgan.
Issues Caused by Lithium Ion Batteries
Lithium-ion batteries can be found in several applications, ranging from notebooks, tablet computers and MP3 players, to mobile phones, cameras, and cordless devices. This means that a lot air passengers will have at least one battery with them when they board the aircraft.
Although these batteries are normally reliable, one problem with them is that they could overheat and catch fire. While this may not be a huge issue and easily contained in other modes of transport or land-based environments, in an enclosed space of an aircraft the prospect of a fire is a serious issue, and can endanger many human lives.
The problem with heat is connected with the potential formation of thermal runaway. This can be explained as auto-acceleration of heat generation, with a quick increase in temperature, defined by the removal of flammable liquids and gases from the product casing. Simply put, a single battery overheating can cause an unmanageable fire, pressure wave, explosion or a combination of all three within a matter of minutes. The main challenge is to avoid propagation between cells, packaging, modules, and surroundings – on an aircraft. The objective is to prolong the time available for emergency measures to be used and for safe landing to occur.
In a perfect world, manufacturers would use cell structures and chemistries that prevent thermal runaway from happening. Conversely, increasing energy densities, requiring batteries to hold more charge, make this extremely difficult, especially in applications where space is critical.
Between March 1991 and January 2016, the US Federal Aviation Administration (FAA) recorded 171 incidents where batteries carried as cargo or baggage caused issues. As the years have passed, a growing number of these incidents are caused by lithium batteries. In some cases, these incidents have caused a catastrophic effect. In 2006, a fire broke out on a UPS DC-8 cargo plane in Philadelphia, which completely destroyed the aircraft. Four years later, another cargo aircraft carrying 81,000 lithium batteries caught fire and crashed soon after take-off from Dubai, causing two fatalities as well. In the following year, two crew members died when a cargo jet crashed into the East China Sea, soon after a crew member reported a fire on board.
What Does the Law Say?
Primary Lithium (UN3090) and Lithium–Ion (UN 3480) are the two key types of lithium batteries. The risk of fire posed by these two varieties of batteries has been recognized by the authorities with both categorized as Class 9 hazardous materials in Title 49 of the Code of Federal Regulations, the Hazardous Materials Regulations and the International Civil Aviation Organization (ICAO) Technical Instructions.
In 1999, a fire at Los Angeles Airport involving 120,000 lithium primary cells resulted in the problem of five separate safety and fire proposals by the National Transportation Safety Board, which performed an investigation for the FAA and the Research & Special Programs Administration. This investigation was conducted together with the issue of FAA Dangerous Goods Advisory Bulletin (DAGB) 00-02 on this subject.
Consecutive studies demonstrated that it is not possible to use halon to adequately suppress primary lithium cell fires. In 2005, the FAA banned primary lithium batteries on passenger aircraft, and the International Civil Aviation Organization (ICAO) followed suit from the beginning of 2015.
In the mean time, FAA Safety Alert for Operators (SAFO) 16001: Risks of Fire or Explosion when Transporting Lithium Ion or Lithium Metal Batteries as Cargo on Passenger and Cargo Aircraft, supports suggestions that before operators participate in the transport of lithium ion or lithium metal batteries in cargo aircraft they should be made aware that both ICAO and leading airframe manufactures (Airbus and Boeing) have proposed that operators carry out risk assessments to determine whether and how they can handle the risks related to the transportation of these items.
Despite the fact that these recommendations are limited, the regulations are becoming a lot tougher. In February 22nd 2016, the ICAO passed a prohibition on the carrying of UN3480 lithium ion batteries as cargo on passenger aircraft. This was effective from 1st April 2016.
The ICAO explained this requirement in detail, and the ICAO ‘Technical Instructions for the Safe Transport of Dangerous Goods by Air’ 2015/16 (Document 9284) also stipulated that lithium-ion cells and batteries must be allowed for transport as a state of charge (SoC) of no more than 30% of their rated design capacity, along with details explaining what constitutes acceptable packaging and labelling.
The carrying of primary lithium and lithium ion batteries may be a concern to increased restriction, but still no limits have been imposed on the transport of these products within the main aircraft cabin. All the same, airlines themselves have recognized a need to address this issue.
Identifying the issues associated with overheating batteries and the need to mitigate fire risk and offer insulation to contain heat spread, Morgan set out to harness the capabilities of its wide range of state-of-the-art insulation technologies in order to sum up a solution.
Morgan’s proficiency in the area of high-performance insulation to prevent the spread of thermal energy is recognized at a global level, not least in the supply of materials that are utilized for encapsulating cockpit voice recorder (CVR) and flight data recorder FDR products, and even in the Oil & Gas sector where its FireMaster® Marine Plus Blanket is utilized to enfold the living quarters in offshore extraction facilities, protecting the structure to permit adequate time for those working on the rig to escape during an outbreak of fire.
A wide variety of combinations and configurations of Morgan’s material range were analyzed and considered to contain fire and heat, reduce additional fire risk, and deal with the issue of heat transfer.
The FireMaster Marine Plus blanket is used at the core of an ideal bag solution. Generally, this product is used to shield FRP composite, aluminum, and steel structures for a prolonged period of time. The outer layer has a hook-and-loop tape fastener and a silicone-coated glass cloth to lock the bag after the contents are placed inside. The materials are selected with the intention of maintaining their integrity even if they get to come into contact with water. Water can be instantly introduced to cool down the overheated battery. The bags’ dimensions are 500 mm x 500 mm and are fixed together with a high-temperature yarn, which is usually employed in welding equipment and heat protection clothing. The bags have been widely tested along with Germanwings, which is part of the Lufthansa group.
This information has been sourced, reviewed and adapted from materials provided by Morgan Advanced Materials.
For more information on this source please visit Morgan Advanced Materials.