4500mAh

4500 mAh refers to a battery’s charge capacity, a rating commonly used for lithium-ion or lithium-polymer cells found in consumer electronics. The unit milliampere-hour indicates how much charge a battery can deliver over time when discharged at a given current.

To compare energy across batteries, it is helpful to convert to watt-hours. Watt-hours equal the product of the capacity in ampere-hours and the nominal voltage: Wh = (mAh × nominal voltage) / 1000. For a typical Li-ion cell with a nominal voltage around 3.7 V, a 4500 mAh pack stores about 16.65 Wh (roughly 16.6 Wh). This provides a convenient way to estimate how much energy is available beyond the raw mAh figure.

In practice, usable energy depends on several factors. The actual delivered capacity decreases with higher discharge rates, aging, and temperature. Charging and power conversion losses also reduce the amount of energy available to a device. Therefore, a labeled 4500 mAh battery may present a lower real-world capacity as it ages or when supplying power to devices with higher current draw.

Common usage and context. A 4500 mAh rating is typical for mid-to-large capacity smartphone batteries and for some portable power banks. In smartphones, it implies extended runtime relative to smaller packs, though actual endurance depends on device efficiency, software, and usage. For power banks, a 4500 mAh rating often translates to roughly one full phone charge, with some variation depending on the receiving device and charging efficiency.

Overall, 4500 mAh summarizes how much charge a battery can hold, while real-world performance also hinges on voltage, efficiency, and aging.