Please
read on for good information about why these Lithium Batteries perform better:
A typical
aluminum encased battery that has better heat dissipation will start out with a
higher cycle life. Dependent upon the
size of the cell the expectant charger cycle life of a smaller LifePO4 cell can
be as much as 4000 charge cycles and follow the same trajectory of the plastic
prismatic cell shown below. The simple
fact is that if you have an application where you want a long life, like for
solar storage, and you do not discharge the cells below their nominal 3.2
voltage you will have a cell that will probably outlive you. Depth of discharge has a very profound effect
on a lithium battery’s life.
What is
the Life Expectancy of the Aluminum Batteries?
- Factor 1: Depth of Discharge…Percentage
of Capacity Used Per Cycle.
- DOD, short for the Depth of Discharge, is
used to describe how deeply the battery is discharged. If we say a battery is
100% fully charged, it means the DOD of this battery is 0%, If we say the
battery have delivered 30% of its energy, here are 70% energy reserved, we say
the DOD of this battery is 30%.
- Factor 2: Discharge Rate, The AMPS
Divided by the Capacity
- To Read the Chart Above, here are Some
Examples
A. All Numbers are at a 1C Discharge Rate, which
is Aggressive…
B. At a 90% Depth of Discharge, Our Batteries
Will Provide 2400 Cycle to 80% State-of-Original-Capacity (SOIC)
C. At a 10% Depth of Discharge (Say, Engine
Starting) Our Batteries Will Provide 35,000 Cycles Until 80% SOIC. Beyond
35,000 Cycles the Battery is Still Functioning but Gradually Losing Capacity,
but not Performance
Conclusion:
By recharging a lithium battery more frequently, thus reducing the DOD (depth
of discharge), the battery cycle life is Increased. Solar is very often a
beneficial method to reduce DOD and increase life!
