Introduction
While DoD receives much attention, charge and discharge rates (C-rate) also play a critical role in determining LiFePO₄ battery cycle life.
Primary SEO Keywords:
LiFePO₄ C-rate, lithium battery charge discharge rate, LiFePO₄ battery degradation factors
Understanding C-Rate
- 1C = full charge or discharge in 1 hour
- 0.5C = full charge or discharge in 2 hours
- 0.2C = full charge or discharge in 5 hours
Lower C-rates generally mean less internal stress.
High C-Rate vs. Cycle Life
Frequent high-current operation leads to:
- Increased internal temperature
- Lithium ion polarization
- Accelerated electrode aging
Even LiFePO₄’s stable chemistry cannot fully eliminate these effects.
Recommended C-Rates for Long Life
- Charging: ≤0.5C preferred
- Discharging: ≤1C continuous
- Peak discharge: Short duration only
Designing systems around average rather than peak loads extends battery lifespan.
Real-World Example: ESS Oversizing
Slightly oversizing battery capacity reduces effective C-rate, delivering:
- Lower heat generation
- Higher usable cycles
- Improved long-term ROI
Key Takeaway
Cycle life is not only about how deep you discharge, but also how fast you charge and discharge.