23501
Finally at very low temperature ( - 40 degrees C ) , this system demonstrates an unprecedented combination of high specific capacitance ( up to 117 F g ( - 1 ) ) , and rapid charging - discharging even at high current density , which is very promising for the progress of energy storage systems with environmentally friendly electrolytes at such very low temperatures .
 None
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: Chemical 
Text: {0} 
Answer:
 None