High power energy storage device additive and high power energy storage device comprising same

Patent metadata

Field	Value
Publication number	US-2018197691-A1
Application number	US-201615740895-A
Country	US
Kind code	A1
Filing date	May 4, 2016
Priority date	Jun 30, 2015
Publication date	Jul 12, 2018
Grant date	—

Abstract

The present invention relates to a high power energy storage device additive and a lithium ion capacitor including the same, and more particularly, to: a preparation method of a new lithium ion capacitor additive which is added to a carbon-based material applied as a cathode active material of a lithium ion capacitor such that the new lithium ion capacitor additive is capable of improving capacity and energy density by electrochemically doping a lithium ion onto an anode; the lithium ion capacitor additive prepared thereby; and the lithium ion capacitor including the lithium ion capacitor additive.
The lithium ion capacitor additive according to the present invention can release 3 mols or more of lithium ions even at a low voltage of 4.4 V or less, and the lithium ion capacitor including the lithium ion capacitor additive according to the present invention can electrochemically dope lithium onto the anode even without performing a pre-doping process using lithium metal as in the conventional lithium ion capacitor.

First claim

1 . A lithium ion capacitor additive represented by Li 6-x Co y M1 1-y O 4-z A z wherein 0≤x≤4, 0≤y≤1 and 0≤z≤1, M1 is any one selected from the group consisting of Ni, Mn and Fe, and A is any one selected from the group consisting of F, Cl and Br.

2 . The lithium ion capacitor additive of claim 1 , wherein the lithium ion capacitor additive is a particle type, and has a particle size of 10 to 50 μm.

3 . The lithium ion capacitor additive of claim 1 , wherein the lithium ion capacitor additive is formed in an anti-fluorite structure.

4 . A cathode active material for a lithium ion capacitor, the cathode active material comprising the lithium ion capacitor additive according to claim 1 and a carbon-based material.

5 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the lithium ion capacitor additive in the cathode active material is characterized in that energy at which a peak intensity caused by a cobalt (Co) atom in XPS becomes a maximum is exhibited at 779.8 eV by Co 2+ when x is 0.

6 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the lithium ion capacitor additive in the cathode active material is characterized in that the energy at which a peak intensity caused by a cobalt (Co) atom in the XPS becomes the maximum is 780.4 eV by Co 3+ when x is more than 0 less than 1.

7 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the lithium ion capacitor additive in the cathode active material is characterized in that the energy at which a peak intensity caused by a cobalt (Co) atom in the XPS becomes the maximum is 781.4 eV by Co4+ when x is more than 1 and less than 1.

8 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the lithium ion capacitor additive in the cathode active material is characterized in that although there is not a change in the location of energy at which a peak intensity caused by an oxygen (O) atom in the XPS becomes a maximum according as x increases when x is 2 or less, the location of energy at which a peak intensity caused by an oxygen (O) atom in the XPS becomes the maximum according as x increases is moved from 529.3 eV to 529.8 eV when x is 2 or more.

9 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the cathode active material has an initial charge-discharge efficiency (QE) according to the following calculation formula 1 of 50% or less:
15 QE =( QD/QC )×100, wherein
QE denotes an initial charge-discharge efficiency of lithium composite metal oxide, QD denotes a discharge capacity (mAh/g) with a cut-off discharge voltage of 2.3V vs. Li/Li+ 20 QC denotes a charge capacity (mAh/g) with a cut-off charge voltage of 4.7V vs. Li/Li+

10 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the carbon-based material is one or more selected from the group consisting of activated carbon, an activated carbon-metal oxide composite, and an activated carbon-conductive polymer composite.

11 . The cathode active material for the lithium ion capacitor of claim 4 , wherein the lithium ion capacitor additive is mixed at a ratio of 10 to 20 parts by weight with the respect to 100 parts by weight of the carbon-based material.

12 . A lithium ion capacitor comprising:
a cathode including the cathode active material according to claim 4 ; an anode including an anode active material; and a separator between the cathode and the anode, wherein the anode receives lithium ions only from the cathode.

13 . The lithium ion capacitor of claim 12 , wherein the anode is pre-doped with lithium in an amount corresponding to 60 to 100% of anode capacity.

Assignees

• Korea Electronics Technology

Inventors

• Song Jun Ho
• Kim Young Jun
• Park Min Sik

Classifications

• H01G11/06

  with one of the electrodes allowing ions to be reversibly doped thereinto, e.g. lithium ion capacitors [LIC] · CPC title

• C01P2002/72

  by d-values or two theta-values, e.g. as X-ray diagram · CPC title

• C01P2004/04

  obtained by TEM, STEM, STM or AFM · CPC title

• C01P2004/51

  Particles with a specific particle size distribution · CPC title

• H01G11/32

  Carbon-based · CPC title