Energizer Universal AAA HR03 Rechargeable Batteries 500mAh (4 Pack)

Energizer Universal AAA HR03 rechargeable batteries are NiMH cells rated at 500mAh capacity and 1.2V nominal voltage, supplied pre-charged in a 4-pack. Each battery can be recharged hundreds of times using any standard NiMH battery charger, replacing disposable AAA alkaline cells in remote controls, wireless mice, keyboards, LED torches, clocks and other low-to-medium drain devices.

The 500mAh capacity suits devices that draw moderate current over extended periods rather than high-drain equipment like digital cameras or gaming controllers, which benefit from higher-capacity cells. Pre-charged from the factory, the batteries are ready to use immediately after unpacking. Charge retention allows them to hold 80% of their charge after 12 months in storage at room temperature, so spares kept in a drawer remain usable without needing a top-up charge before deployment.

Energizer incorporates recycled battery materials into the cell construction, reducing the environmental footprint compared to manufacturing from virgin materials alone. The cells are manufactured to deliver up to 5 years of use under typical household charging patterns, with performance degrading gradually rather than failing abruptly. Each cell weighs approximately 12.5g (50g total pack weight) and follows the standard AAA form factor, fitting any device designed for AAA batteries.

How many times can these batteries be recharged?

Energizer rates these cells for hundreds of recharge cycles. The exact number depends on usage patterns, charger quality, and depth of discharge before recharging. Regularly fully discharging NiMH cells before recharging can reduce total cycle life compared to partial discharge cycles.

Do they arrive charged?

Yes. The batteries are pre-charged at the factory and ready to use immediately after unpacking. They retain approximately 80% of their charge after 12 months in storage, so even if they've been on a shelf for some time, they should still function without an initial charge.

What charger do I need?

Any standard NiMH battery charger rated for AAA cells will work. The charger must be designed for NiMH chemistry rather than NiCd or alkaline. Energizer produces dedicated chargers, but third-party options are also compatible provided they support the correct chemistry and cell size.

Are these suitable for high-drain devices like cameras?

The 500mAh capacity is on the lower end for rechargeable AAA cells. High-drain devices such as digital cameras, gaming controllers and camera flashes perform better with higher-capacity cells (900mAh+). These 500mAh cells suit moderate-drain applications like remote controls, wireless mice, clocks and LED torches.