Method for connecting in parallel a first electrical storage device, in particular a battery, preferably a lithium-ion battery, and a second electrical storage device, in particular a battery, preferably a lithium-ion battery, - wherein the first electrical storage device and the second electrical storage device each have an open-circuit voltage (U Bat1, U Bat2) and an impedance (R1 or R2) - wherein the first electrical storage device is connected to connection terminals (K e) via two first electrical conductors for charge withdrawal or charge supply, wherein a first switch (S 1) is provided in one of the first electrical conductors, and wherein the electrical connection between the first storage device and one of the connection terminals (K e) can be established or interrupted by means of the first switch (S 1), - wherein the second electrical storage device is connected to the connecting terminals (K e) via two second electrical conductors, wherein a second switch (S 2) is provided in one of the second electrical conductors, and wherein the electrical connection between the second storage device and one of the connecting terminals (K e) can be established or interrupted by means of the second switch (S 2), - wherein the open-circuit voltage U Bat1 of the first storage device is greater than the open-circuit voltage U Bat2 of the second storage device, wherein, when charge is withdrawn, the electrical connection between the first storage device and the connection terminals (K e) is established by means of the first switch (S 1) and the electrical connection between the second storage device and the connection terminals (K e) is interrupted by means of the second switch (S 2), so that initially only charge is withdrawn from the first storage device, and in that the electrical connection between the second storage device and the connection terminals (K e) is established by means of the second switch (S 2) when the difference between the voltage dropped at the connection terminals of the first storage device and the open-circuit voltage (U Bat2) of the second storage device is less than a predetermined switch-on differential voltage (V d), characterised in that for the switch-on differential voltage (V d) applies: V d < I max * R, wherein I max represents the smaller value of the maximum permissible current when connecting or disconnecting the second storage device and of the maximum current, which may be taken from the first and/or second storage device (1, 2) in a permissible manner, and R represents the impedance of the storage devices (1, 2) effective after the parallel connection of the first and second storage devices (1, 2). - wherein the first electrical storage device and the second electrical storage device each have an open-circuit voltage (U Bat1, U Bat2) and an impedance (R1 or R2) - wherein the first electrical storage device is connected to connection terminals (K e) via two first electrical conductors for charge withdrawal or charge supply, wherein a first switch (S 1) is provided in one of the first electrical conductors, and wherein the electrical connection between the first storage device and one of the connection terminals (K e) can be established or interrupted by means of the first switch (S 1), - wherein the second electrical storage device is connected to the connecting terminals (K e) via two second electrical conductors, wherein a second switch (S 2) is provided in one of the second electrical conductors, and wherein the electrical connection between the second storage device and one of the connecting terminals (K e) can be established or interrupted by means of the second switch (S 2), - wherein the open-circuit voltage U Bat1 of the first storage device is greater than the open-circuit voltage U Bat2 of the second storage device, wherein, when charge is withdrawn, the electrical connection between the first storage device and the connection terminals (K e) is established by means of the first switch (S 1) and the electrical connection between the second storage device and the connection terminals (K e) is interrupted by means of the second switch (S 2), so that initially only charge is withdrawn from the first storage device, and in that the electrical connection between the second storage device and the connection terminals (K e) is established by means of the second switch (S 2) when the difference between the voltage dropped at the connection terminals of the first storage device and the open-circuit voltage (U Bat2) of the second storage device is less than a predetermined switch-on differential voltage (V d), characterised in that for the switch-on differential voltage (V d) applies: V d < I max * R, wherein I max represents the smaller value of the maximum permissible current when connecting or disconnecting the second storage device and of the maximum current, which may be taken from the first and/or second storage device (1, 2) in a permissible manner, and R represents the impedance of the storage devices (1, 2) effective after the parallel connection of the first and second storage devices (1, 2).