Gloves are not essential, but highly recommended --- When replacing a car battery there are three potential hazards that relate to safety: - electrical hazard - the battery is capable of generating 100's of amps' worth of current. You want to avoid short the two terminals with something like a wrench, cable or your own body. Gloves can help reduce the risk of shorting the battery with your hands, but the prudent thing to do is not do anything to short the battery terminals. - chemical hazard - battery acid is highly acidic and not to to be messed with. In case the battery water overflows or develops a leak gloves would be essential here, though I don't expect this to be too much of an issue while changing maintenance-free batteries. - falling hazard - batteries are heavy and can cause considerable damage if one were to fall on your toes. Gloves won't do much good here (unless they provide better grip). In all situations, the onus is on you to be careful while replacing the battery. Wearing gloves will not guarantee you your safety.