For the purpose of this appendix, both a battery and battery system is referred to as a battery. A battery system consists of the battery and any protective, monitoring, and alerting circuitry or hardware inside or outside of the battery. It also includes vents (where necessary) and packaging. The Federal Aviation Administration (FAA) has issued several special conditions (SCs) for non-rechargeable lithium battery installations on transport category airplanes (and these SCs have been adopted by the DASA). These SCs are located in this appendix. Applicants, who propose using these SCs for their project, must submit a MCRI indicating their intentions to the DASA.
In this policy, the terms “must,” “should,” and “recommend” have specific meanings:
The term “must” refers to a regulatory requirement that is mandatory for design approval. The functional impact of the term “must” is that the requirement has to be met to achieve design approval.
The term “should” refers to instructions for a particular acceptable method of compliance (MOC). The functional impact of the term “should” is that all proposed alternative MOC are evaluated through the issue paper process.
The term “recommendation” refers to a recommended practice that is optional. There is no functional impact of the term “recommend” because it is optional.
“End Item” is used in this appendix and is defined in RTCA/DO-227A, Minimum Operational Performance Standards (MOPS) for Non-Rechargeable Lithium Batteries, appendix D.
Recent events involving rechargeable and non-rechargeable lithium batteries prompted a broad evaluation of these energy storage technologies. In January 2013, two independent events involving rechargeable lithium-ion batteries revealed unanticipated failure effects. On July 12, 2013, an event involving a non-rechargeable lithium battery in an emergency locator transmitter installation demonstrated additional unanticipated failure effects. The FAA has been issuing SCs for certification projects involving the installations of non-rechargeable lithium batteries. At this time, all of the published SCs have been the same. These SCs are listed below.
In lieu of title 14, Code of Federal Regulations (14 CFR) 25.1353(b) (1) through (4) at amendment 25-123 or 25.1353(c) (1) through (4) at earlier amendments, each non-rechargeable lithium battery installation must:
Be designed to maintain safe cell temperatures and pressures under all foreseeable operating conditions to prevent fire and explosion.
Be designed to prevent the occurrence of self-sustaining, uncontrollable increases in temperature or pressure.
Not emit explosive or toxic gases, either in normal operation or as a result of its failure, that may accumulate in hazardous quantities within the airplane.
Meet the requirements of 25.863.
Not damage surrounding structure or adjacent systems, equipment, or electrical wiring from corrosive fluids or gases that may escape in such a way as to cause a major or more severe failure condition.
Have provisions to prevent any hazardous effect on airplane structure or systems caused by the maximum amount of heat it can generate due to any failure of it or its individual cells.
Have a failure sensing and warning system to alert the flightcrew if its failure affects safe operation of the airplane.
Have a means for the flightcrew or maintenance personnel to determine the battery charge state if the battery’s function is required for safe operation of the airplane.
Note: A battery system consists of the battery and any protective, monitoring, and alerting circuitry or hardware inside or outside of the battery. It also includes vents (where necessary) and packaging. For the purpose of these special conditions, a “battery” and “battery system” are referred to as a battery.