Method for detecting a short circuit within an energy store, comprising: - detecting a first current (I n-1) flowing through the energy store at a first time (t n-1), - detecting a first voltage (U n-1) provided by the energy store at the first time (t n-1), - detecting a second current (I n) flowing through the energy store at a second time (tn) subsequent to the first time (t n-1), - detecting a second voltage (Un) provided by the energy store at the second time (tn) subsequent to the first time (t n-1), - establishing whether the energy store is in a charging state, a discharging state or an idle state on the basis of the detected first current (I C), - performing a first, second or third detection step on the basis of the established charging state, a short circuit being detected as present in the first detection step, which is performed if the energy store is in the idle state, if the second voltage (Un) is less than the first voltage (U n-1), in particular less than the first voltage (U n-1) minus a first constant (ε 1), a short circuit being detected as present in the second detection step, which is performed if the energy store is in the charging state, if the second voltage (Un) is less than the first voltage (U n-1), in particular less than the first voltage (U n-1) minus a second constant (ε 2), and the third detection step, which is performed if the energy store is in the discharging state, being characterised in that a short circuit is detected as present if the second voltage (Un) is less than the first voltage (U n-1) minus a difference voltage (ΔU) and minus a third constant (ε 3), an internal resistance (R C) of the energy store being estimated, and the difference voltage (ΔU) being determined on the basis of the internal resistance (R C) and the difference between the second current (I n) and the first current (I n-1). - detecting a first current (I n-1) flowing through the energy store at a first time (t n-1), - detecting a first voltage (U n-1) provided by the energy store at the first time (t n-1), - detecting a second current (I n) flowing through the energy store at a second time (tn) subsequent to the first time (t n-1), - detecting a second voltage (Un) provided by the energy store at the second time (tn) subsequent to the first time (t n-1), - establishing whether the energy store is in a charging state, a discharging state or an idle state on the basis of the detected first current (I C), - performing a first, second or third detection step on the basis of the established charging state, a short circuit being detected as present in the first detection step, which is performed if the energy store is in the idle state, if the second voltage (Un) is less than the first voltage (U n-1), in particular less than the first voltage (U n-1) minus a first constant (ε 1), a short circuit being detected as present in the second detection step, which is performed if the energy store is in the charging state, if the second voltage (Un) is less than the first voltage (U n-1), in particular less than the first voltage (U n-1) minus a second constant (ε 2), and the third detection step, which is performed if the energy store is in the discharging state, being characterised in that a short circuit is detected as present if the second voltage (Un) is less than the first voltage (U n-1) minus a difference voltage (ΔU) and minus a third constant (ε 3), an internal resistance (R C) of the energy store being estimated, and the difference voltage (ΔU) being determined on the basis of the internal resistance (R C) and the difference between the second current (I n) and the first current (I n-1). a short circuit being detected as present in the first detection step, which is performed if the energy store is in the idle state, if the second voltage (Un) is less than the first voltage (U n-1), in particular less than the first voltage (U n-1) minus a first constant (ε 1), a short circuit being detected as present in the second detection step, which is performed if the energy store is in the charging state, if the second voltage (Un) is less than the first voltage (U n-1), in particular less than the first voltage (U n-1) minus a second constant (ε 2), and the third detection step, which is performed if the energy store is in the discharging state, being characterised in that a short circuit is detected as present if the second voltage (Un) is less than the first voltage (U n-1) minus a difference voltage (ΔU) and minus a third constant (ε 3), an internal resistance (R C) of the energy store being estimated, and the difference voltage (ΔU) being determined on the basis of the internal resistance (R C) and the difference between the second current (I n) and the first current (I n-1).