Shaving
— Dry. Dry shaving is suitable for shavers specifically designed for use on dry skin, excluding the application of creams, foams, or similar products. It's important to recognize that these models might have moisture-resistant qualities and tolerate water washes (as described below), but these features don't imply compatibility with wet shaving.
— Wet/dry. Shavers that can shave not only "dry", but also on wet skin, which is applied with foam or other shaving agent.
Wet shaving is considered more gentle and is well suited for people with sensitive skin. However, such shavers are much more expensive than “dry” ones — after all, the shaving head must have certain features (so as not to clog with foam and not smear it instead of shaving hairs).
Waterproof
Models feature waterproof casing with varying levels of protection, often indicated by two numbers. The first number pertains to dust resistance and is often marked as X. The second number reflects moisture resistance, particularly water. For instance, IPX3 and IPX4 offer splash protection, IPX5 and IPX6 enable shower use, while
electric shavers with IPX7 can be submerged underwater for up to 30 minutes.
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.