hi sages- have been charging my own batteries since jack was pres. have an old 100amp sears charger instead of having it done at the cleaners. here is my issue for folks knowledgeable on chargers. some of my cars sit for a long time. the batteries slowly discharge themselves and sometimes a cell shorts out and an otherwisegood battery goes to hell. was thinking of getting what is now called a battery maintainer charger. think it used to be called a trickle charger or a float charger. anyway it is continuously connected to a long sitting vehicle and it delivers a tiny small charge when the level drops in voltage. keeping the battery fully charged seems to prevent a sitting battery cell from a crapout. the charger automatically shuts off when the battery is fully charged. does any sage here have any experience with this type. i have none. do they work as advertised; any recommendation on brand/ model. notice that harbor freight has one for 4.99 on sale made by centech. do know continuous charging w/o automatic shutoff can evaporate the electrolyte. thanks tons for your advice. oldduke