The ABYC standard for battery installation, including movement, is as follows...(underscore is mine).
10.7 INSTALLATION
NOTE: When installing flooded batteries on a sailing vessel, consideration should be given so that the orientation of the battery minimizes the uncovering of battery plates while heeling.
10.7.1 Battery mounting materials and surfaces shall withstand electrolyte attack.
10.7.2 Provision shall be made to contain incidental leakage and spillage of electrolyte.
NOTE: Consideration should be given to:
1. the type of battery installed (e.g. liquid electrolyte or immobilized electrolyte).
2. the boat in which the battery is installed (e.g. angles of heel for sailboats, and accelerations for powerboats).
10.7.3 Fasteners for the attachment of battery boxes or trays shall be isolated from areas intended to collect spilled electrolyte.
[10.7.4 Batteries, as installed, shall be restrained to not move more than one inch (25mm) in any direction when a pulling force of twice the battery weight is applied through the center of gravity of the battery as follows:
10.7.4.1 vertically for a duration of one minute, and
10.7.4.2 horizontally and parallel to the boat's centerline, for a duration of one minute fore and one minute aft, and
10.7.4.3 horizontally and perpendicular to the boat's centerline for a duration of one minute to starboard and one minute to port.
(In Xiamen, China, at the South Coast Yard)