Lithium secondary battery

Patent metadata

Field	Value
Publication number	US-12230782-B2
Application number	US-201917290130-A
Country	US
Kind code	B2
Filing date	Nov 1, 2019
Priority date	Nov 2, 2018
Publication date	Feb 18, 2025
Grant date	Feb 18, 2025

Abstract

The present invention relates to a lithium secondary battery manufactured by forming a negative electrode free battery and then forming a lithium metal on the negative electrode current collector by charging.
In the lithium secondary battery, since lithium metal is formed on the negative electrode current collector in the state of being blocked with the atmosphere, the generation of the conventional surface oxide layer (native layer) formed on the negative electrode does not occur inherently, thereby preventing the reduction of the efficiency and lifetime characteristics of the battery.

First claim

The invention claimed is:

1. A lithium secondary battery comprising a positive electrode, a negative electrode, a separator interposed therebetween and an electrolyte,
wherein the positive electrode includes:
a positive electrode current collector; and
a positive electrode mixture comprising a positive electrode active material and a lithium metal compound,

the negative electrode includes only a negative electrode current collector before charging,
the negative electrode current collector consists essentially of a metal selected from the group consisting of copper, stainless steel, aluminum, nickel, titanium, silver, and aluminum-cadmium alloy,
the lithium metal compound has an irreversible capacity of 200 mAh/g or more, and
during charging of the lithium secondary battery, lithium metal of the lithium metal compound included in the positive electrode mixture is released from the positive electrode and is directly deposited on the negative electrode current collector.

2. The lithium secondary battery according to claim 1 , wherein the lithium metal compound comprises one or more selected from the group consisting of Li 6 CoO 4 , Li 2 MnO 3 , Li 2 MoO 3 , a composite including Li 2 O and a metal, a composite including LiF and a metal, Li 3 N and LiN 3 .

3. The lithium secondary battery according to claim 1 , wherein the lithium metal disposed on the negative electrode current collector is formed through one time charging in a voltage range of 4.8 V to 2.5 V.

4. The lithium secondary battery according to claim 1 , wherein a protective layer is formed on the negative electrode current collector on a side facing the separator.

5. The lithium secondary battery according to claim 1 , wherein the positive electrode mixture comprises the positive electrode active material and the lithium metal compound in a weight ratio of the positive electrode active material:the lithium metal compound of 5:95 to 95:5.

6. The lithium secondary battery according to claim 5 , wherein the positive electrode active material is present as a mixture with the lithium metal compound or forms a core-shell structure with the lithium metal compound.

7. The lithium secondary battery according to claim 5 , wherein the positive electrode active material comprises at least one selected from the group consisting of LiCoO 2 , LiNiO 2 , LiMnO 2 , LiMn 2 O 4 , Li(Ni a Co b Mn c )O 2 (0<a<1, 0<b<1, 0<c<1, a+b+c=1), LiNi 1−Y Co Y O 2 , LiCo 1−Y MnYO 2 , LiNi 1−Y MnYO 2 (wherein 0≤Y<1), Li(Ni a Co b Mn c )O 4 (0<a<2, 0<b<2, 0<c<2, a+b+c=2), LiMn 2−z Ni z O 4 , LiMn 2−z Co z O 4 (wherein 0<Z<2), Li x M y Mn 2−y O 4−z A z (wherein 0.9≤x≤1.2, 0<y<2, 0≤z<0.2, M is at least one of Al, Mg, Ni, Co, Fe, Cr, V, Ti, Cu, B, Ca, Zn, Zr, Nb, Mo, Sr, Sb, W, Ti or Bi, and A is one or more anion having a −1 or −2 valence), Li 1+a Ni b M′ 1−b O 2−c A′ c (wherein 0≤a≤0.1, 0≤b≤0.8, and 0≤c<0.2, M′ is at least one member selected from the group consisting of stable elements having six-coordination sites of Mn, Co and Mg, and Al, and A′ is at least one anion having −1 or −2 valence), LiCoPO 4 , and LiFePO 4 .

8. The lithium secondary battery according to claim 1 , wherein the positive electrode mixture comprises at least one selected from the group consisting of Li x VO 3 (1≤x≤6), Li 3 Fe 2 (PO 4 ) 3 , Li 3 Fe 2 (SO 4 ) 3 , Li 3 V(PO 4 ) 3 , MnO 2 , MoO 3 , VO 2 , V 2 O 5 , V 6 O 13 , Cr 3 O 8 , CrO 2 , Al 2 O 3 , ZrO 2 , AlPO 4 , SiO 2 , TiO 2 , and MgO.

9. The lithium secondary battery according to claim 1 , wherein the positive electrode mixture has a loading amount of 1 to 10 mAh/cm 2 .

10. The lithium secondary battery according to claim 4 , wherein the protective layer comprises at least one of a lithium ion conductive polymer or an inorganic solid electrolyte.

11. The lithium secondary battery according to claim 10 , wherein the lithium ion conductive polymer comprises polyethylene oxide (PEO), polyacrylonitrile (PAN), polymethylmethacrylate (PMMA), polyvinylidene fluoride (PVDF), polyvinylidene fluoride-hexafluoropropylene (PVDF-HFP).

12. The lithium secondary battery according to claim 10 , wherein the inorganic solid electrolyte comprises at least one selected from the group consisting of thio-LISICON(Li 3.25 Ge 0.25 P 0.75 S 4 ), Li 2 S—SiS 2 , LiI—Li 2 S—SiS 2 , LiI—Li 2 S—P 2 S 5 , LiI—Li 2 S—P 2 O 5 , LiI—Li 3 PO 4 —P 2 S 5 , Li 2 S—P 2 S 5 , Li 3 PS 4 , Li 7 P 3 S 11 , Li 2 O—B 2 O 3 , Li 2 O—B 2 O 3 —P 2 O 5 , Li 2 O—V 2 O 5 —SiO 2 , Li 2 O—B 2 O 3 , Li 3 PO 4 , Li 2 O—Li 2 WO 4 —B 2 O 3 , LiPON, LiBON, Li 2 O—SiO 2 , LiI, Li 3 N, Li 5 La 3 Ta 2 O 12 , Li 7 La 3 Zr 2 O 12 , Li 6 BaLa 2 Ta 2 O 12 , Li 3 PO (4−3/2w) N w (w is w<1), and Li 3.6 Si 0.6 P 0.4 O 4 .

13. The lithium secondary battery according to claim 10 , wherein the protective layer further comprises at least one lithium salt selected from the group consisting of LiCl, LiBr, LiI, LiClO 4 , LiBF 4 , LiB 10 Cl 10 , LiPF 6 , LiCF 3 SO 3 , LiCF 3 CO 2 , LiAsF 6 , LiSbF 6 , LiAlCl 4 , CH 3 SO 3 Li, CF 3 SO 3 Li, LiSCN, LiC(CF 3 SO 2 ) 3 , (CF 3 SO 2 ) 2 NLi, (FSO 2 ) 2 NLi lithium chloroborane, lithium lower aliphatic carboxylate, lithium tetraphenyl borate, and lithium imide.

14. The lithium secondary battery according to claim 10 , wherein the protective layer has a thickness of 10 nm to 50 μm.

15. The lithium secondary battery according to claim 2 , wherein the composite including Li 2 O and a metal is a composite including Li 2 O and Co.

16. The lithium secondary battery according to claim 15 , wherein the composite including Li 2 O and Co comprises Li 2 O and Co in a weight ratio of 3:1.

17. The lithium secondary battery according to claim 2 , wherein the composite including LiF and a metal is a composite including LiF and Co.

18. The lithium secondary battery according to claim 17 , wherein the composite including LiF and Co comprises LiF and Co in a weight ratio of 6:1.

19. A lithium secondary battery comprising a positive electrode, a negative electrode, a separator interposed therebetween and an electrolyte,
wherein the positive electrode includes:
a positive electrode current collector; and
a positive electrode mixture comprising a positive electrode active material and a lithium metal compound,

the negative electrode includes only a negative electrode current collector before charging,
the negative electrode current collector consists essentially of copper, stainless steel, aluminum, nickel, or titanium,
during charging of the lithium secondary battery, lithium metal of the lithium metal compound included in the positive electrode mixture is released from the positive electrode and is directly deposited on the negative electrode current collector.

20. The lithium secondary battery according to claim 10 , wherein the inorganic solid electrolyte comprises LiPON, Li 3 N, LixLa 1−x TiO 3 (0<x<1) or Li 2 S—GeS—Ga 2 S 3 .

Assignees

• Lg Energy Solution Ltd

Inventors

• Uhm Insung
• Park Sin Young
• Kim Taegon
• Jang Minchul
• Jung Wang Mo
• Lee Boram
• Son Byoungkuk
• Park Eunkyung
• Ha Seongmin

Classifications

• H01M2004/021

  Physical characteristics, e.g. porosity, surface area · CPC title

• H01M10/446

  Initial charging measures · CPC title

• H01M10/0525

  Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries · CPC title

• H01M4/667

  in the form of layers, e.g. coatings · CPC title

• H01M4/661

  Metal or alloys, e.g. alloy coatings (H01M4/669 take precedence) · CPC title