when you buy a new battery they are not fully charged usually only 65 to 70 % even though the guy at the counter will tell ya oh yeah we charge all our batteries b.s. unless you see a battery charging station where they have their battery rack usually right behind it look around the corner to see if there are any batteries on a multiple charging station most likely not. they unload em off a truck and sell em. the specific gravity of a fully charged battery 6 or 12 volt will be 1.280" at each cell you can buy a specific gravity meter for cheap. 1.0" is the specific gravity of distilled water so if you have to add water use only distilled water not tap water. when i buy a new battery unless it is an emergency i charge it at low amps for a couple days.then i check the gravity.on a normal battery with lead plates once you hook it up and draw juice from it that will "set the plates" so if it is only 75%charged that's all it will ever be charged no matter how many times you charge it. an agm {glass mat] battery will take a fresh charge up to 100 % when drawn down or not fully charged when installed.the fiberglass mats are not like lead plate batteries they are mostly used on motorcycles which take a hell of a beating.but they have em for cars too.
