A brief history of Starting, Lighting and Ignition (SLI) batteries:
Since the beginning of the 20th century, when gasoline and diesel internal combustion engine technology emerged, vehicles have continued to electrify processes to improve reliability, comfort and safety. Manual cranking became unnecessary with the introduction of the starter motor, and magnetic ignition was replaced by a battery ignition that required an electric generator and a rechargeable battery.
Soon electric headlights and windshield wipers were added. Larger engines with higher cranking requirements and further electrification saw system voltages double from 6V positive-ground to 12V negative-ground (and some 24V systems) in the 1960s. Generators changed to higher efficiency alternators, and batteries began to standardize around the current 12V design.
Starting, Lighting and Ignition (SLI) Batteries continued to improve with mechanical improvements (grid, separator, case, cover and terminal) and electrochemical enhancements (lead alloys, active material and electrolyte additives).
High Maintenance Deep Cycle batteries with antimony alloys branched off into a category of their own to support battery-powered lighting and equipment.
Low or maintenance-free calcium plate alloys largely replaced high maintenance water-consuming antimony alloys in starting and ignition batteries. This led to the introduction of flooded sealed and accessible vent maintenance-free transportation batteries in the 1970s.
Battery design changes throughout the 80s and 90s largely kept pace with growing maintenance, reliability and performance demands as well as original equipment manufacturer demands for component weight reductions.
Starting and Ignition Batteries transitioned from being purchased “mostly” based on their capacity in Amp Hour (“AH”) or minutes of reserve capacity (“RC”) to being marketed mainly based on their cold cranking (“CCA”) ratings.
Deep Cycle / Lighting batteries gravitated from high antimony and high water consumption to low antimony and low maintenance technologies. The lead-acid starting, lighting and ignition battery has survived over one hundred years of cost-reducing manufacturing advancements and a radical performance and maintenance transformation.
As of now, vehicle evolution has accelerated, and the electrical demands are still handled by the same power supply systems used since the 70s. For the first time in 100 years, the average battery life of lead-acid batteries is declining. The starting and ignition lead-acid batteries are again being challenged to transform in the transportation market segment and flooded lead-acid Deep Cycle energy storage. Lighting batteries are now being overtaken by sealed maintenance-free Semi-Traction and general-purpose Deep Cycle AGM and GEL technologies and battery systems made with advanced cell chemistries such as lithium-ion.