Under ideal conditions (25degC) with 100% DOD, batteries may retain at least 80% of their charge/discharge energy after 6,000 cycles, 70% after 9,000 cycles, and 60% after 12,000 cycles, respectively.
[pdf] LiFePO4 batteries can achieve an impressive 2000 to 4000 charge cycles, significantly outlasting traditional lithium-ion batteries. This extended lifespan is due to their stable chemical structure, which enhances their thermal stability and safety.
[pdf] Solar installer Sunrun said batteries can last anywhere between 5-15 years. That means a replacement likely will be needed during the 20-30 year life of a solar system. Battery life expectancy is mostly driven by usage cycles.
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