A battery module comprising: a first charging terminal and a second charging terminal for connecting the battery module to an external power source for charging of the battery module or a load for providing power to said load; a battery cell arrangement having a maximum charge voltage and having a first terminal and a second terminal, wherein the first terminal is connected to the first charging terminal, a switch arrangement including at least a first switching device connected between the second terminal of the battery cell arrangement and the second charging terminal, said first switching device being operable to switch the battery module between a discharging mode in which power is provided to said load and a charging mode in which power is provided from the external power source to the battery cell arrangement, the first switching device being in a current passing state for discharging the battery cell arrangement in the discharging mode, and a controller configured to control operation of the switch arrangement between said discharging mode and said charging mode, wherein, upon detection of a reverse polarity connection of the external power source at the first and second charging terminals, the controller is configured to operate the first switching device to switch to a current blocking state, wherein the first switching device has a blocking voltage equal to, or higher than, at least twice the maximum charge voltage of the battery cell arrangement, and wherein the controller is configured to control operation of said switch arrangement in response to an input signal provided by a sensor (330, 335) of said battery module. a first charging terminal and a second charging terminal for connecting the battery module to an external power source for charging of the battery module or a load for providing power to said load; a battery cell arrangement having a maximum charge voltage and having a first terminal and a second terminal, wherein the first terminal is connected to the first charging terminal, a switch arrangement including at least a first switching device connected between the second terminal of the battery cell arrangement and the second charging terminal, said first switching device being operable to switch the battery module between a discharging mode in which power is provided to said load and a charging mode in which power is provided from the external power source to the battery cell arrangement, the first switching device being in a current passing state for discharging the battery cell arrangement in the discharging mode, and a controller configured to control operation of the switch arrangement between said discharging mode and said charging mode, wherein, upon detection of a reverse polarity connection of the external power source at the first and second charging terminals, the controller is configured to operate the first switching device to switch to a current blocking state, wherein the first switching device has a blocking voltage equal to, or higher than, at least twice the maximum charge voltage of the battery cell arrangement, and wherein the controller is configured to control operation of said switch arrangement in response to an input signal provided by a sensor (330, 335) of said battery module.