Lithium Ion batteries don't use lead and will cut the weight at least by half. A 12v 10ah lead acid run 6lbs where Lithium will be 2.14. these weights came from Amazon site.

1) Weight: Lithium-ion batteries are one-third the weight of lead acid batteries.

2) Efficiency: Lithium-ion batteries are nearly 100% efficient in both charge and discharge, allowing for the same amp hours both in and out. Lead acid batteries’ inefficiency leads to a loss of 15 amps while charging and rapid discharging drops voltage quickly and reduces the batteries’ capacity.

3) Discharge: Lithium-ion batteries are discharged 100% versus less than 80% for lead acid. Most lead acid batteries do not recommend more than 50% depth of discharge.

4) Cycle Life: Rechargeable lithium-ion batteries cycle 5000 times or more compared to just 400-500 cycles in lead acid. Cycle life is greatly affected by higher levels of discharge in lead acid, versus only slightly affected in lithium-ion batteries.

5) Voltage: Lithium-ion batteries maintain their voltage throughout the entire discharge cycle. This allows for greater and longer-lasting efficiency of electrical components. Lead acid voltage drops consistently throughout the discharge cycle.

6) Cost: Despite the higher upfront cost of lithium-ion batteries, the true cost of ownership is far less than lead acid when considering life span and performance.

7) Environmental Impact: Lithium-ion batteries are a much cleaner technology and are safer for the environment.