This document applies to small and medium sized rechargeable lithium batteries and battery systems that are permanently installed on aircraft. For the purpose of this document, a battery or battery system is considered permanently installed equipment when it is included as part of the type design of the aircraft (or supplemental/amended type design). This standard also applies to rechargeable lithium batteries contained within Portable Electronic Devices (PEDs) that are part of the type design. This document does not apply to primary lithium batteries or large rechargeable lithium batteries or battery systems.