| abstract |
Methods of improving the performance of energy storage devices are described. The method can include providing an energy storage device, which can be a lithium ion battery. Provided energy storage devices may include electrodes and room temperature ionic liquid electrolytes. The room temperature ionic liquid electrolyte may include a lithium salt, wherein the concentration of the lithium salt in the room temperature ionic liquid is greater than 1.2M, such as 2.4M to 3.0M. The method may also include charging and discharging the provided energy storage device. Other methods described include providing an energy storage device including electrodes and a room temperature ionic liquid electrolyte, heating the energy storage device to a temperature above ambient temperature (eg, 45°C), and charging and discharging the energy storage device. Other approaches include using room-temperature ionic liquid electrolytes with high lithium salt concentrations and heating energy storage devices. |