Lead-acid batteries have been the standard in electric wheelchairs for many years. These batteries are divided into two main types flooded lead-acid and sealed lead-acid (SLA). Flooded lead-acid batteries require regular maintenance, including water refills, but they are generally more affordable upfront. Sealed lead-acid batteries, on the other hand, are maintenance-free and can be used in any orientation. While lead-acid batteries are heavier and bulkier, they are known for their reliability and cost-effectiveness. However, they typically have a shorter lifespan compared to other battery types.