Shaving heads / foil
The number of individual shaving heads (for rotary models) or foils (see "Type") in the shaver design.
More heads/foils allow for more coverage and a better shave. Note that rotary shavers traditionally have at least
2 heads, but there can be
one foil. The most popular are
3 head/foil models.Number of cuts
The number of cutting movements made by shaver blades per minute. Determines the number of hairs that the device can cut in a given amount of time. The higher the number of cuts, the more efficient and faster the shaving process.
Replacement nozzle model
Model of replacement head(s) compatible with electric shaver. This data will be useful primarily when looking for spare nozzles.
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.