School Bus Battery System
Over their lifetime, school bus batteries are required to deliver consistently high cold cranking amps for engine starting, which can be incredibly challenging during frigid weather. With the engine off, a high cycle reserve capacity is required to support key-off loads such as interior lighting, blower fans, dash systems and chair lifts. School buses spend a significant amount of time in storage, during which batteries self-discharged. Therefore the batteries need to be able to accept charge current after spending an extended period in a discharged state. The alternator is the sole charging source, and undercharging of the battery is expected due to the alternator being overloaded. Alternator voltage is often poorly regulated, causing long-term damage to the batteries.
Battery failure is most commonly caused by acid stratification, extreme temperatures and destructive over-the-road vibration. Acid stratification naturally occurs in flooded lead-acid batteries and leads to a decline in capacity and charge acceptance. AGM technology and acid mixing technology for flooded lead-acid will mitigate acid stratification. A maintenance-free spillproof battery is highly desirable.