I'd take all of them to the scrapyard,cash them in,an buy one new (or good used battery from a wreck),before wasting time and electricity,and possibly hurting the charger trying to re-charge those batteries..any battery that has sat more than 6 months is likely junk,the plates will be all sulphated..
I had 5 old batteries hanging around for years,about a year ago I took them to the recycler and got 6 bucks each for them,and I took the 36 bucks,went to another junkyard I frequent,and bought 3 used batteries,two Duralast from a diesel pickup that were new in october of '07,and a Interstate from a Honda Civvic that fit my tractor perfect only 3 months old,for 30 bucks..no more aggravation and tripping over dead batteries,or fears of fire from leaving them on the charger all the time..
I have heard the "wives tale" about leaving batteries on cement..far as I can tell the only harm that might cause is if any acid leaks out of the battery,it'll dissolve the concrete..personally I dont see how current can flow through a plastic case and through cement,even wet or damp cement,myself..
I know for fact having the top of the battery dirty and damp can let current discharge across the terminals and eventually kill it though..put a multi-meter or voltmeter's leads on the positive post and the negative to the case,if its dirty or moist enough,you'll see the needle rise indicating a slight short curcuit.my shop teacher in school showed us that,and said thats why its important to keep the battery clean..
I had 5 old batteries hanging around for years,about a year ago I took them to the recycler and got 6 bucks each for them,and I took the 36 bucks,went to another junkyard I frequent,and bought 3 used batteries,two Duralast from a diesel pickup that were new in october of '07,and a Interstate from a Honda Civvic that fit my tractor perfect only 3 months old,for 30 bucks..no more aggravation and tripping over dead batteries,or fears of fire from leaving them on the charger all the time..
I have heard the "wives tale" about leaving batteries on cement..far as I can tell the only harm that might cause is if any acid leaks out of the battery,it'll dissolve the concrete..personally I dont see how current can flow through a plastic case and through cement,even wet or damp cement,myself..
I know for fact having the top of the battery dirty and damp can let current discharge across the terminals and eventually kill it though..put a multi-meter or voltmeter's leads on the positive post and the negative to the case,if its dirty or moist enough,you'll see the needle rise indicating a slight short curcuit.my shop teacher in school showed us that,and said thats why its important to keep the battery clean..
