Akkuikä

Akkuikä refers to the length of time a rechargeable battery remains usable and meets performance requirements before its capacity, power output, or reliability fall below an acceptable level. It is influenced by calendar aging (time) and cycle aging (charging/discharging events) and depends on chemistry, design, and operating conditions. In most consumer lithium-ion batteries, capacity fades gradually with both aging paths; higher temperatures and deeper discharges accelerate degradation. An increase in internal resistance raises heat and reduces available power.

Key measures of Akkuikä include the battery's nominal capacity, its current capacity (often expressed as state of health), and its internal impedance. Manufacturers typically define a service life in cycles or in calendar years, with a common end-of-life criterion around 70-80 percent of the original capacity or a threshold impedance. Real-world lifespans vary: consumer Li-ion devices often retain usable capacity for 2-5 years, while electric-vehicle batteries commonly target 8-15 years or several thousand cycles, depending on duty cycle and thermal management.

Factors influencing Akkuikä are temperature, depth of discharge, charging rate (C-rate), state of charge management, storage state, and manufacturing quality. Proper use can extend life: operate at moderate temperatures, avoid exposing the battery to heat, charge to about 80-90 percent for daily use, and avoid full discharges. For long-term storage, a partial charge (roughly 40-60 percent) is advised. Regular calibration of the device’s battery gauge and a capable battery management system help maintain accurate SoC readings.

Finally, Akkuikä has economic and environmental implications, influencing replacement timing, second-life use, and recycling. Ongoing advances in chemistry and thermal management continue to extend usable life and reliability of rechargeable batteries.