摘要 |
An energy storage apparatus including at least first and second energy storage devices to supply, or also consume, an electric current. At least the second energy storage device is an electrochemical energy storage device. A control device controls at least supply of electric current by at least one of the energy storage devices and can also control consumption of electric current by at least one of the energy storage devices. Energy density of the second energy storage device is higher than energy density of the first energy storage device; energy density is defined as the ratio between energy that can be stored in the energy storage device in a charged state and weight of the energy storage device. The control device can trigger the first energy storage device to supply electric current when the electric current exceeds a predetermined threshold value for the current strength. |