Hearing aid system, comprising - a hearing aid, which has a rechargeable battery for the power supply and a first data memory for storing operating data, and - a charging station, which has a nonvolatile second data memory, wherein the charging station is configured to at least temporarily charge the battery of the hearing aid when the hearing aid is arranged in a charging position with respect to the charging station, wherein the hearing aid is configured to store operating data continuously during operation in the first data memory for subsequent automated learning processes, and is configured to transfer operating data stored in the first data memory to the charging station when the hearing aid is arranged in a transfer position with respect to the charging station, wherein the hearing aid is configured to store as operating data information with respect to an existing hearing situation and/or acoustic measurement data collected by the hearing aid and/or a user input of the user preference with respect to the signal processing function for an existing hearing situation and/or an existing value of a parameter relating to the signal processing function of the hearing aid, wherein the charging station is configured to store operating data transferred from the hearing aid in the second data memory, characterized in that the second data memory is dimensioned larger than the first data memory, the charging station is furthermore configured to transfer older operating data stored in the second data memory, which were transferred during preceding charging processes to the second data memory and stored therein as part of a long-term history of operating data, back to the hearing aid when the hearing aid is arranged in the transfer position, and the hearing aid furthermore has a computer unit, which is configured to adapt at least one parameter relating to a signal processing function of the hearing aid by means of a machine learning algorithm on the basis of the older operating data transferred from the charging station to the hearing aid. - a hearing aid, which has a rechargeable battery for the power supply and a first data memory for storing operating data, and - a charging station, which has a nonvolatile second data memory, wherein the charging station is configured to at least temporarily charge the battery of the hearing aid when the hearing aid is arranged in a charging position with respect to the charging station, wherein the hearing aid is configured to store operating data continuously during operation in the first data memory for subsequent automated learning processes, and is configured to transfer operating data stored in the first data memory to the charging station when the hearing aid is arranged in a transfer position with respect to the charging station, wherein the hearing aid is configured to store as operating data information with respect to an existing hearing situation and/or acoustic measurement data collected by the hearing aid and/or a user input of the user preference with respect to the signal processing function for an existing hearing situation and/or an existing value of a parameter relating to the signal processing function of the hearing aid, wherein the charging station is configured to store operating data transferred from the hearing aid in the second data memory, characterized in that the second data memory is dimensioned larger than the first data memory, the charging station is furthermore configured to transfer older operating data stored in the second data memory, which were transferred during preceding charging processes to the second data memory and stored therein as part of a long-term history of operating data, back to the hearing aid when the hearing aid is arranged in the transfer position, and the hearing aid furthermore has a computer unit, which is configured to adapt at least one parameter relating to a signal processing function of the hearing aid by means of a machine learning algorithm on the basis of the older operating data transferred from the charging station to the hearing aid.