Electric energy storage system
An electric energy storage system having a novel structure which exhibits a ling cycle life, rapid charging-discharging characteristics and a high energy density. The electric energy storage system comprises: an anode comprised of a first material that performs interalation-deintercalation of cation as an anode active material; a cathode comprised of a second material that may form an electric doublelayer with anion as a cathode active materials; and a electrolyte including lithium salt, the electrolyte including the cation and anion. Due to a high difference between anode and cathode in capacity to store the electric energy, most electrochemical impact that occurs in the process of intercalation-deintercalation of electric energy is absorbed into cathode and active material used for anode is activated carbon having a very high resistance to electrochemical and structural impact, so that its operation life is elongated and it has rapid charging-discharging characteristics. The electric energy storage system can complement the defects of a conventional technology.
1 . An electric energy storage system comprising:
an anode including a first material that performs interalation-deintercalation of cation as an anode active material;
a cathode including a second material that may form an electric double layer with anion as a cathode active material; and
an electrolyte including the cation and the anion, said electrolyte including both lithium salt and ammonium salt.
2 . An electric energy storage system as claimed in claim 1 , wherein said anode active material includes an oxide comprised of lithium and a transitional metal.
3 . An electric energy storage system as claimed 2 , wherein said transitional metal is at least one selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Mo and Ni.
4 . An electric energy storage system as claimed 2 , wherein said oxide is at least one selected from the group consisting of LiCoO2, LiMnO2, LiMn2O4, LiNiO2, LiMoO2, LiV2O5 and LiCoXNi1-XO2(0<x<1).
5 . An electric energy storage system as claimed 1 , wherein said cathode active material includes activated carbon.
6 . An electric energy storage system as claimed 5 , wherein a specific surface area of said activated carbon is no less than 200 m 2 /g.
7 . An electric energy storage system as claimed 1 , wherein said lithium salt is at least one selected from the group consisting of LiBF4, LiAsF6, LiClO4 and LiPF6.
8 . An electric energy storage system as claimed 1 , wherein said ammonium salt is at least one selected from the group consisting of tetraethylammonium tetrafluoroborate ((CH3CH2)4NBF6), tetraethylammonium hexafluorophosphate ((CH3CH2)4NPF6), and tetraethylammonium perclorate ((CH3CH2)4NCIO4).
9 . An electric energy storage system comprising:
an anode including a first material that performs intercalation-deintercalation of cation as an anode active material;
a cathode including a second material that may form an electric double layer with anion as a cathode active material; and
an electrolyte including lithium salt, the electrolyte including the cation and anion.
10 . An electric energy storage system as claimed in claim 9 , wherein said anode active material includes an oxide comprised of lithium and a transitional metal.
11 . An electric energy storage system as claimed 10 , wherein said transitional metal is at least one selected from the group consisting of Ti, V, Cr, Mn, Fe, Co, Mo and Ni.
12 . An electric energy storage system as claimed 10 , wherein said oxide is at least one selected from the group consisting of LiCoO2, LiMnO2, LiMn2O4, LiNiO2, LiMoO2, LiV2O5 andLiCoXNi1-XO2(0<x<1).
13 . An electric energy storage system as claimed 9 , wherein said cathode active material includes activated carbon.
14 . An electric energy storage system as claimed 9 , wherein a specific surface area of said activated carbon is no less than 200 m 2 /g.
15 . An electric energy storage system as claimed 9 , wherein said lithium salt is at least one selected from the group consisting of LiBF4, LiAsF6, LiClO4 and LiPF6.
16 . An electric energy storage system as claimed 9 , wherein said ammonium salt is at least one selected from the group consisting of tetraethylammonium tetrafluoroborate, tetraethylammonium hexafluorophosphate and tetraethylammonium perchlorate.