Electronic shelf label system comprising - a plurality of electronic display modules, wherein each display module comprises at least one battery -for the power supply of the display module, at least one passive, non-luminous display unit and a low-energy radio system which is adapted for a bidirectional data transmission in an ISM band with a low-energy radio protocol, - a base station with a housing in which a low-energy radio system is arranged which is adapted for a bidirectional data transmission in the ISM band between the base station ('3) and each display module with the low-energy radio protocol, - wherein the low-energy radio protocol is programmed in such a manner that data transmissions from a low-energy radio system of one of the display modules to the low-energy radio system in the base station take place exclusively in time slots, wherein as a result of the time slot method, the low-energy radio system knows when transmissions from the low-energy radio system of the display modules are to be expected, - wherein the transmission power of the low-energy radio systems (2b, 5) operated with the low-energy radio protocol is a maximum of 10 mW both in the base station and also the display modules, - a WLAN radio system arranged in the housing of the base station in addition to the low-energy radio system, which is likewise adapted for data transmission in the ISM band but according to the IEEE standard 802.11 for communication in radio networks between the base station and a plurality of WLAN clients, wherein in cases of joint use of the ISM band, collisions with the data transmissions between the electronic display modules and the base station can occur, - a controller which is adapted in such a manner that transmissions of the WLAN radio system arranged in the housing of the base station are prevented when and as long as a data transmission takes place from at least one low-energy radio system of one of the display modules to the low-energy radio system in the base station, wherein however transmissions of the WLAN client which still possibly take place in this time interval are transmitted parallel to the WLAN radio system of the base station. - a plurality of electronic display modules, wherein each display module comprises at least one battery -for the power supply of the display module, at least one passive, non-luminous display unit and a low-energy radio system which is adapted for a bidirectional data transmission in an ISM band with a low-energy radio protocol, - a base station with a housing in which a low-energy radio system is arranged which is adapted for a bidirectional data transmission in the ISM band between the base station ('3) and each display module with the low-energy radio protocol, - wherein the low-energy radio protocol is programmed in such a manner that data transmissions from a low-energy radio system of one of the display modules to the low-energy radio system in the base station take place exclusively in time slots, wherein as a result of the time slot method, the low-energy radio system knows when transmissions from the low-energy radio system of the display modules are to be expected, - wherein the transmission power of the low-energy radio systems (2b, 5) operated with the low-energy radio protocol is a maximum of 10 mW both in the base station and also the display modules, - a WLAN radio system arranged in the housing of the base station in addition to the low-energy radio system, which is likewise adapted for data transmission in the ISM band but according to the IEEE standard 802.11 for communication in radio networks between the base station and a plurality of WLAN clients, wherein in cases of joint use of the ISM band, collisions with the data transmissions between the electronic display modules and the base station can occur, - a controller which is adapted in such a manner that transmissions of the WLAN radio system arranged in the housing of the base station are prevented when and as long as a data transmission takes place from at least one low-energy radio system of one of the display modules to the low-energy radio system in the base station, wherein however transmissions of the WLAN client which still possibly take place in this time interval are transmitted parallel to the WLAN radio system of the base station.