46 CFR § 120.352
Battery categories
April 15, 2021
This section applies to batteries installed to meet the requirements of §120.310 of this part for secondary sources of power to vital loads, or sources of power to final emergency loads.
(a) Large. A large battery installation is one connected to a battery charger having an output of more than 2 kilowatts (kw), computed from the highest possible charging current and the rated voltage of the battery installation.
(b) Small. A small battery installation is one connected to a battery charger having an output of 2 kw or less, computed as above.