Battery Management System ( or BMS ) spreads the charge and discharge regularly over the cells of a battery. This ensures correct and evenly distributed power flows, which lengthens the lifespan of a battery and reduces the risk of damage. A BMS can often be found in lithium batteries as the charge is spread over a number of cells rather than lead batteries with simpler plate designs.
Glossary - B
BMS
BS (Bottle Supplied)
For Yuasa batteries, the BS suffix equates to 'Bottle Supplied' (an acid pack). A battery supplied with an acid pack, and must be filled to activate the battery. This allows for a longer shelf life as the battery is not activated at factory.