Weight: Li-Ion batteries are one-third the weight of lead-acid batteries.
Efficiency: Li-Ion batteries are nearly 100% efficient in both charge and discharge.
Discharge: You can discharge 100% of a Li-Ion battery versus less than 80% for lead acid.
Cycle Life: Rechargeable Li-Ion batteries cycle 5000 times or more compared to just 400-500 cycles in lead acid.
Voltage: Li-Ion batteries maintain their voltage throughout the entire discharge cycle. Lead-acid voltage drops throughout the discharge cycle.
Cost: Despite the higher upfront cost of Li-Ion batteries, due to the longer lifespan the true cost of ownership is significantly lower.