Nonaqueous Lithium-Type Power Storage Element

Patent metadata

Field	Value
Publication number	US-2018269486-A1
Application number	US-201715761084-A
Country	US
Kind code	A1
Filing date	Jan 20, 2017
Priority date	Jan 22, 2016
Publication date	Sep 20, 2018
Grant date	—

Abstract

Provided is a nonaqueous lithium-type power storage element in which a lithium compound is included in positive electrode, wherein energy loss due to voltage decrease under high temperatures and high voltages is reduced, and the high-load charge and discharge cycle characteristics are exceptional.

First claim

1 . A nonaqueous lithium-type storage element, comprising a positive electrode containing a lithium compound other than a positive electrode active material, a negative electrode, a separator, and a nonaqueous electrolytic solution containing lithium ions,
wherein the positive electrode comprises a positive electrode power collector, and a positive electrode active material layer located at one surface or both surfaces of the positive electrode power collector, and containing the positive electrode active material, the negative electrode comprises a negative electrode power collector, and a negative electrode active material layer located at one surface or both surfaces of the negative electrode power collector, and containing the negative electrode active material, 2≤C≤300, where C (ppm) is concentration of Na and/or K element, contained in the positive electrode active material layer, and 1.0≤D≤15, 10≤E≤100, 0.2≤C/D≤38, and 0.1≤C/E≤7.2, where D (g/m 2 ) is basis weight of the lithium compound other than the positive electrode active material, contained in the positive electrode active material layer, per one surface of the positive electrode, and E (g/m 2 ) is basis weight of the positive electrode active material contained in the positive electrode active material layer, per one surface of the positive electrode.

2 . The nonaqueous lithium-type storage element according to claim 1 , wherein the lithium compound is lithium carbonate.

3 . The nonaqueous lithium-type storage element according to wherein the concentration C is 2.5≤C≤300.

4 . The nonaqueous lithium-type storage element according to claim 1 , wherein 0.01≤D/E≤0.52.

5 . The nonaqueous lithium-type storage element according to claim 1 , wherein A 1 is 40% to 99%, where A 1 is area overlap ratio of fluorine mapping to oxygen mapping, binarized based on average value of brightness, in an element mapping obtained using SEM-EDX of the surface of the positive electrode.

6 . The nonaqueous lithium-type storage element according to claim 1 , wherein A 2 is 10% to 60%, where A 2 is area overlap ratio of fluorine mapping to oxygen mapping, binarized based on average value of brightness, in the element mapping obtained using SEM-EDX of the cross-section of the BIB processed positive electrode.

7 . The nonaqueous lithium-type storage element according to claim 1 , wherein
(h) Fe/F is 1.01 or higher,
where Fe (F) is static capacitance after carrying out charging and discharging cycle 60,000 times under an environmental temperature of 25° C., a cell voltage of from 2.2 V to 3.8 V, a rate of an electric current value of 200 C, and subsequently carrying out charging under a constant voltage of 4.5 V for 1 hour, and F (F) is static capacitance before the charging and discharging cycle, for the nonaqueous lithium-type storage element.

8 . The nonaqueous lithium-type storage element according to claim 1 , using a positive electrode precursor comprising the positive electrode active material layer containing the positive electrode active material containing activated carbon, and the lithium compound other than the positive electrode active material, wherein 20≤C 0 ≤1300 ppm, where Co (ppm) is concentration of Na and/or K element contained in the positive electrode active material layer of the positive electrode precursor; 8.0≤D 0 ≤50.0, where D 0 (g/m 2 ) is basis weight of the lithium compound other than the positive electrode active material contained in the positive electrode active material layer, per one surface of the positive electrode precursor;10≤E 0 ≤100, 0.2≤C 0 /D 0 ≤38, and 0.1≤C 0 /E 0 ≤7.2, where E 0 (g/m 2 ) is basis weight of the positive electrode active material contained in the positive electrode active material layer, per one surface of the positive electrode precursor.

9 . The nonaqueous lithium-type storage element according to claim 1 , wherein 1.00≤C 1 /C 2 ≤15.00, where C 1 (ppm) is concentration of Na and/or K element contained in the negative electrode active material layer, and C 2 (ppm) is concentration of Na and/or K element contained in the electrolytic solution,
the lithium compound is one or more compounds selected from lithium carbonate, lithium oxide, lithium hydroxide, lithium fluoride, lithium chloride, lithium bromide, lithium iodide, lithium nitride, lithium oxalate, and lithium acetate,
0.1 μmX 1 ≤10 μm, where X 1 is average particle diameter of the lithium compound, 2 μm≤Y 1 ≤20 μm, and X 1 <Y 1 , where Y 1 is average particle diameter of the positive electrode active material, and an amount of the lithium compound contained in the positive electrode is 1% by weight to 50% by weight, based on the total weight of the positive electrode active material layer.

10 . The nonaqueous lithium-type storage element according to claim 9 , wherein an amount of lithium, calculated from an area of peaks in −40 ppm to 40 ppm, in a solid 7 Li-NMR spectrum of the positive electrode active material layer, is 10.0×10 −4 mol/g to 300×10 −4 mol/g.

11 . The nonaqueous lithium-type storage element according to claim 9 , wherein the nonaqueous electrolytic solution contains at least one organic solvent selected from ethylene carbonate, propylene carbonate, butylene carbonate, vinylene carbonate and fluoroethylene carbonate.

12 . The nonaqueous lithium-type storage element according to claim 9 , wherein the nonaqueous electrolytic solution contains at least one of LiPF 6 and LiBF 4 .

13 . The nonaqueous lithium-type storage element according to claim 9 , wherein concentration of LiN(SO 2 F) 2 in the nonaqueous electrolytic solution is 0.3 mol/L to 1.5 mol/L, based on the total amount of the nonaqueous electrolytic solution.

14 . The nonaqueous lithium-type storage element according to claim 9 , wherein the positive electrode power collector and the negative electrode power collector are metal foils not having through holes.

15 . The nonaqueous lithium-type storage element according to claim 9 , wherein
(a) Ra·F, that is a product of Ra and F, is 0.3 to 3.0, (b) E/V is 15 to 50,
where Ra(Ω) is initial inner resistance at a cell voltage of 4 V, F(F) is static capacitance, E(Wh) is electric energy, and V(L) is volume of a casing containing an electrode laminated body, in the nonaqueous lithium-type storage element.

16 . The nonaqueous lithium-type storage element according to claim 9 , wherein
(e) Rd/Ra is 0.9 to 3.0, (g) Re/Ra is 0.9 to 2.0
where Ra (Ω) is initial inner resistance at a cell voltage of 4 V, F (F) is static capacitance, Rd(Ω) is inner resistance at 25° C., after storage for 2 months at a cell voltage of 4 V and an environmental temperature of 60° C., and Re(Q) is inner resistance after carrying out charging and discharging cycle 60,000 times under an environmental temperature of 25° C., a cell voltage of from 2.2 V to 3.8 V, and a rate of 300C, in the nonaqueous lithium-type storage element.

17 . The nonaqueous lithium-type storage element according to claim 1 , wherein
the negative electrode active material contains a carbon material, which is capable of intercalating/releasing lithium ions, the positive electrode active material contains activated carbon, the positive electrode contains the lithium compound other than the positive electrode active material in an amount of 1% by weight to 50% by weight, based on the total weight of the positive electrode active material layer, Al concentration of the nonaqueous electrolytic solution is 1 ppm to 300 ppm.

18 . The nonaqueous lithium-type storage element according to claim 7 , wherein the

Assignees

• Asahi Chemical Ind

Inventors

• Umetsu Kazuteru
• Hirakawa Yuichiro
• Kimura Yuima
• Morita Hitoshi
• Okada Nobuhiro

Classifications

• H01M4/0404

  by coating on electrode collectors · CPC title

• H01M10/0566

  Liquid materials · CPC title

• H01M10/44

  Methods for charging or discharging (circuits for charging H02J7/00) · CPC title

• H01M4/5825

  Oxygenated metallic salts or polyanionic structures, e.g. borates, phosphates, silicates, olivines · CPC title

• H01M4/364

  as mixtures · CPC title