cell which remains closed and does not release either gas or liquid when operated within the limits specified by the manufacturer
Note 1 to entry: A sealed cell may be equipped with a safety device to prevent a dangerously high internal pressure and is designed to operate during its life in its original sealed state.
[SOURCE IEC 60050-482:2004: 482.05.17)
Source: IEC 61892-6, Mobile and fixed offshore units – Electrical installations – Part 6: Installation, Third Edition, December 2013. Global Standards