The manufacturers nowadays provide different types of batteries. Some are Gel or AGM maintenance free batteries, Trojan/US batteries, lithium batteries. 

GEL, AGM batteries usually have 12months warranty. We'd keep the surface clean and dry. Charge it twice a month even we don't use it. 

Trojan , US batteries maintenance. We'd better sure the water inside are in suitable volume. 

Lithium battery normally has 3~5 years warranty. Relion from USA are expensive and excellent quality. Roy Pow is cost effective.