Lithium-ion Cell Advantage vs. Lead Acid

  • Cell Cycle Life: 20,000 shallow cycles or ~10 year
  • Longer Life Cycles: Exceed 2,000 full cycles, 5 times better than Lead Acid with 80% capacity left. Other companies claim higher full cycles with 50% capacity left that ours achieve as well.
  • Higher Discharge Power: 6.6 times of Lead Acid
  • Less Charging Time: Less than 2 hours
  • Less Self Discharge Rate: Less than 2% monthly, Lead Acid is 30%
  • Less Weight and Size: 50% of Lead Acid
  • High Temperature: Can operate at 70°C without life degradation
  • Low Temperature: Can operate in -30°C with slight performance degrade
  • Maintenance Free: Flooded Lead Acid need constant distilled water maintenance
  • Lithium does not Freeze
  • Safer: No Explosion, No Fire
  • Non Toxic to the Environment
  • 98% Energy efficient

Discharge Capability of Lead-Acid Battery

Rated capacity of the Lead-Acid Battery, based on 20-hour rate, is indicated by the capacity value when the battery of fully charged state is discharged to specified end of voltage.

The 20-hour rate is equal to 0.05C of Lead-Acid current rate and it is very low current rate condition. (Rated Current of Lead-Acid : 0.5C)

Generally, Lead-acid battery has poor capability under high discharge current. So it is easy to sacrifice its containing capacity at this higher discharge rate (In other word, Lead-acid battery can not used all rated capacity at higher discharge rate). Because of slow electrolyte diffusion into the electrode, the H2SO4 content is reduced in the micro pore that is occur IR drop rapidly.

Consequently, the capacity shows the tendency to be reduced remarkably as the discharge rate increase. Lithium-ion capacity rating is at 1 hour discharge rate and do not have the capacity decrease issue that Lead-Acid batteries have.

The Table1 and Fig 1 below shows rated capacity with discharge current between a lead-acid rated at 12V22Ah at 20-hour rate vs StarkPower’s Lithium-ion rated at 12V20Ah at 1 hour rate. The lead-acid rated at 22Ah only provided 14Ah with a degrease voltage and the Lithium-ion provided the full rated 20Ah at a steady voltage at their voltage cut-off point.