| abstract |
Provided herein are energy storage devices (400, 500, 600A, and 600B) having an anode comprising a layered double hydroxide (702) comprising divalent ions and trivalent ions, both of which contribute to energy storage. In some embodiments, the specific combination of device chemistry, active materials, and electrolytes (430) described herein form storage devices that operate at high voltage and exhibit the capacity of a battery and the power performance of supercapacitors in one device. |