A lithium battery taken outside its voltage, current or temperature limits can be ruined, and some failures end in fire. A battery management system (BMS) watches those limits cell by cell and disconnects the battery before they're crossed. A drop-in lithium battery has one built in. A bank built from loose cells needs an external one.
ABYC E-13 is the lithium standard. Panbo's summary says it applies to systems of 600 Wh or more, about 50 Ah at 12 V, and section 13.7 requires a BMS on every lithium battery.
What a surveyor checks
Find out what's installed: chemistry, make, capacity, and whether the BMS is built in or external. Ask for the maker's documents with the charge, discharge and temperature limits. Check that chargers and the alternator are set for lithium, and what happens to the alternator if the BMS disconnects. Check the restraint: Panbo notes E-13 asks for no visible movement.
In the report
"House bank, four LiFePO4 cells in series with no battery management system; charging from an alternator regulated for lead-acid. Fit a BMS to ABYC E-13 and the cell maker's limits, and set charge sources for lithium, before further use." See lithium batteries without BMS.