How long do Ford Energi batteries last?

I'm curious to know about the longevity of Ford Energi batteries. As an environmentally conscious consumer, I'm interested in investing in a hybrid vehicle that can offer reliable performance and reduced emissions. However, I'm hesitant to make a purchase without a clear understanding of how long the battery will last. Can you provide some insight into the average lifespan of Ford Energi batteries and any factors that might affect their durability?