When it comes to the longevity of battery storage systems, you can generally expect them to last between 10 and 12 years. That said, some premium models can keep going for up to 15 years or even longer with the right care and maintenance.
[pdf] 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] For homes or businesses that need to store electricity, PV storage systems typically have a service life of 10 to 15 years, depending on the choice of battery type, such as lithium or lead-acid batteries.
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