IEC 62933-5-3:2023 applies to those instances when a BESS undergoes unplanned modifications. Such modifications can involve one or more of the following:
- changes in energy storage capacity;
- changes of chemistries, design and manufacturer of the accumulation subsystem;
- changes of a subsystem component using non-OEM parts,
- changes to the mode of operation,
- changes of the installation site, or
- changes in an accumulation subsystem due to an installation of reused or repurposed batteries.
Any such modification can impair the original state of safety of the BESS.
This document complements IEC 62933-5-2, which relates to the overall safety aspects of a BESS. The requirements covered by this document are applied in addition to the requirements in IEC 62933-5-2 in accordance with each situation.