SLA and VRLA are different acronyms for the same battery, Sealed Lead Acid or Valve Regulated Lead Acid. This battery type has the following characteristics: Maintenance-free, leak-proof, position insensitive. Batteries of this kind have a safety vent to release gas in case of excessive internal pressure build up. AGM, Absorbed Glass Mat refers to a specific type of SLA/VRLA where the electrolyte is absorbed into separators between the plates consisting of sponge like fine glass fiber mats An automotive battery or car battery is a rechargeable battery that is used to start a motor vehicle. Its main purpose is to provide an electric current to the electric-powered starting motor, which in turn starts the chemically-powered internal combustion engine that actually propels the vehicle. Once the engine is running, power for the car's electrical systems is still supplied by the battery, with the alternator charging the battery as demands increase or decrease. Lithium Iron phosphate (LiFePO4) batteries are a type of lithium ion (Li-Ion) rechargeable battery. Their benefits over the more traditional cobalt-based Li-Ion batteries are increased power output, faster charging, reduced weight and longer lifetime. The batteries also have better safety characteristics and do not explode under extreme conditions. LiFePO4 batteries also eliminate the concerns of cobolt entering the environment through improper disposal once they have expired