Rail vehicle comprising an energy storage system having an energy storage device and a transformer, a method of operating such a rail vehicle, and a method of assembling a train composition comprising a rail vehicle carriage

1 . A rail vehicle comprising:

a rail vehicle carriage;

a traction equipment comprising at least one traction converter and at least one traction motor;

a high-voltage conductor and a current collector, the high-voltage conductor electrically connects the traction equipment to the current collector; and

an energy storage system with an energy storage device

wherein the energy storage system comprises a transformer which is associated with the energy storage device and is electrically connected to the energy storage device and to the high-voltage conductor and wherein the high-voltage conductor can selectively be supplied with high-voltage alternating current via the current collector by an external power supply and/or by means of the energy storage system.

2 . A rail vehicle according to claim 1 , wherein the high-voltage conductor is connectable to an external power supply via the current collector without components influencing the voltage in such a way that the high-voltage conductor and the traction equipment can substantially be supplied with the voltage and the frequency of the current of the external power supply.

3 . A rail vehicle according to claim 1 , wherein the high-voltage conductor and the traction equipment are adapted to be supplied with an AC voltage of substantially 25 kV at a frequency of substantially 60 Hz or 50 Hz.

4 . A rail vehicle according to claim 1 , wherein the energy storage system has an electrical frequency filter.

5 . A rail vehicle according to claim 1 , wherein the rail vehicle has at least one double-deck carriage.

6 . A rail vehicle according to claim 1 , wherein the rail vehicle comprises a plurality of rail vehicle carriages, wherein the at least one battery is arranged in exactly one battery carriage or in several of the rail vehicle carriages.

7 . A rail vehicle according to claim 6 , wherein the rail vehicle carriage comprising the battery is accessible for passengers to pass through the interior of the rail vehicle carriage.

8 . A rail vehicle according to claim 6 , wherein the rail vehicle carriage, which comprises the battery, comprises a lower level and an upper level.

9 . The rail vehicle according to claim 8 , wherein the battery is arranged on the lower level.

10 . A rail vehicle according to claim 1 , wherein the rail vehicle comprises a charge status display by means of which the charge status of the batteries can be displayed.

11 . A rail vehicle according to claim 10 , wherein a remaining charging time until the battery is fully charged can be displayed by the charge status display.

12 . A rail vehicle according to claim 1 , wherein power consumers of the rail vehicle which are not used for traction are connectable or are at least partially electrically connected to a battery converter.

13 . A rail vehicle carriage for a rail vehicle according to claim 1 , comprising:

a high-voltage conductor electrically connectable to traction equipment comprising at least one traction converter and at least one traction motor and to a current collector; and

an energy storage system with an energy storage device,

wherein the energy storage system has a transformer which is assigned to the energy storage device and is electrically connected to the energy storage device and to the high-voltage conductor.

14 . The rail vehicle carriage for a rail vehicle according to claim 13 , wherein the energy storage device is a battery.

15 . The rail vehicle according to claim 1 , wherein the energy storage device is a battery.

16 . The rail vehicle according to claim 1 , wherein the high-voltage conductor and the traction equipment are adapted to be supplied with an AC voltage of substantially 15 kV at a frequency of substantially 16.66 Hz.