Hello, it can be replaced. Rechargeable shavers in the world now generally have built-in rechargeable batteries, usually 1.2V rechargeable batteries. One section, or two sections in series. Ten years ago, nickel-chromium batteries were mainly used. Later, nickel-metal hydride batteries appeared. In recent years, lithium batteries have also been used in rechargeable shavers.
Different battery brands have different installation methods. Some are soldered on top, as shown in the photo above. Some are stuck. Some have one battery and others two in series. As shown below
Because nickel-chromium or nickel-metal hydride batteries want to be compared with lithium batteries, they are inexpensive, do not need protection boards and the circuit of charging and discharging does not need to be too complicatediqued. The short circuit current is large and the internal resistance is small. The electric motor runs more powerfully. Therefore, most products still use nickel-chromium-nickel-metal hydride rechargeable batteries. Only a few high-end products use lithium batteries. When the battery is no longer durable, we can disassemble it to see the battery type, then purchase a suitable battery and replace it ourselves. If you are soldering a battery, you need a soldering iron to help you. Be careful not to confuse the positive and negative poles!