Battery type
— Li-Ion. Currently, the prevailing battery type is Lithium-ion (Li-Ion), known for its high energy density, compact size, and light weight. Li-Ion batteries offer approximately 400 charge-discharge cycles on average. These batteries exhibit minimal self-discharge and lack a significant "memory effect" (capacity reduction due to charging a partially drained battery). However, they are sensitive to cold temperatures and require high-quality charging currents.
— Li-pol. Lithium-polymer (Li-Pol) batteries maintain stable output voltage even during significant discharge. These batteries offer an average lifespan of about 800 charge-discharge cycles. Unlike some battery types, Li-Pol batteries don't exhibit a memory effect, and they operate reliably within a wide temperature range of -20 to +40°C. However, they are sensitive to deep discharge and overcharging. To address this, specialized chargers employing suitable power supply algorithms for the lithium polymer context are recommended for maintenance.
— Ni-Mh. Nickel-metal hydride (Ni-MH) batteries excel in managing substantial charge and discharge currents, making them suitable for power-demanding electric motors and rapid charging. These batteries now boast impressive longevity, enduring around 1000 to 1500 charge-discharge cycles, while maintaining an eco-friendly nature. In comparison to Li-Ion, Ni-MH batteries appear bulkier and add weight to the device, yet they offer a more economical option.
Battery capacity
While higher battery capacity theoretically extends a device's operation on a single charge, practical considerations are more complex. Ampere-hours are a specific unit, comparable only among batteries with the same voltage. For differing voltages, capacity must be converted to watt-hours for accurate comparison. Furthermore, actual tool battery life depends on consumption and performance, not just battery properties. Comparing battery capacity is meaningful only when models share the same voltage and capabilities. Operating time is a more informative parameter for comparison.
Operating time
The average runtime of electric shavers on a full battery charge, without recharging, is generally overestimated due to factors like hair length, density, and trimmer usage. Manufacturer claims for runtime tend to be higher than actual usage.
Longer runtimes require heavier and more expensive powerful batteries. Most shavers offer around
45 minutes of runtime, while some models provide up to
1 hour or as low as
30 minutes of operation.
Charge level indicator
The presence in the design of the electric shaver
charge level indicator.
It's important to highlight that in this context, an indicator refers specifically to a visual representation of the charge level. This could manifest as a battery icon or a percentage displayed on the
display. Such an indicator significantly simplifies battery monitoring, minimizing the possibility of being unexpectedly left with a depleted battery.