Electrochemical apparatus and electronic apparatus including same

Patent metadata

Field	Value
Publication number	US-12438145-B2
Application number	US-202418645907-A
Country	US
Kind code	B2
Filing date	Apr 25, 2024
Priority date	Oct 25, 2021
Publication date	Oct 7, 2025
Grant date	Oct 7, 2025

Abstract

An electrochemical apparatus includes a positive electrode, a negative electrode, a separator, and an electrolyte. The positive electrode includes a first positive electrode material and a second positive electrode material. The first positive electrode material has good cycling stability and high initial coulombic efficiency, and the second positive electrode material has a high specific capacity and low initial coulombic efficiency during the first charge. This can compensate for the active lithium loss caused by the formation of SEI.

First claim

What is claimed is:

1. An electrochemical apparatus, comprising a positive electrode, a negative electrode, and an electrolyte; wherein
the positive electrode comprises a positive electrode current collector and a positive electrode material layer on at least one surface of the positive electrode current collector, and the positive electrode material layer comprises a first positive electrode material shown in Formula (I):

Li

1
+
x

⁢

Fe
y

⁢

Mn
z

⁢

M

1
-
y
-
z

⁢

PO

4
-
t

⁢

A
t

,

Formula
⁢

(
I
)

wherein
−0.1<x<0.1, 0<y≤1, 0≤z≤1, 0<y+z≤1, 0≤t<0.2, M comprises at least one of Ti, Zr, V, or Cr, and A comprises at least one of S, N, F, Cl, or Br; and
a second positive electrode material shown in Formula (II);

Li

1
+
r

⁢

Mn

1
-
p

⁢

X
p

⁢

O

2
-
s

⁢

T
s

,

Formula
⁢

(
II
)

wherein
−0.1<r<0.2, 0≤p<0.2, 0≤s<0.2, X comprises at least one of Fe, Co, Ni, Ti, Zn, Mg, Al, V, Cr, or Zr, and T comprises at least one of S, N, F, Cl, or Br; and
the positive electrode satisfies

0.5
≤

R
×
P
/
Q

≤
16

,

wherein
R is a numerical value representing a resistance of the positive electrode (in Ω); P is a numerical value representing a compacted density of the positive electrode (in g/cm 3 ); and Q is a numerical value representing a single-sided surface density of the positive electrode (in g/mm 2 ),
wherein Q is calculated according to Q=1540.25×m/Ar, where m is a numerical value representing a mass of the positive active material layer (in g), and Ar is a numerical value representing an area of the positive active material layer (in mm 2 ).

2. The electrochemical apparatus according to claim 1 , wherein 1.5≤R×P/Q≤10.

3. The electrochemical apparatus according to claim 1 , wherein R≤3.5.

4. The electrochemical apparatus according to claim 1 , wherein 1.6<P<2.6.

5. The electrochemical apparatus according to claim 1 , wherein 0.16<Q<0.45.

6. The electrochemical apparatus according to claim 1 , wherein a mass ratio of the first positive electrode material to the second positive electrode material is 5:1 to 99:1.

7. The electrochemical apparatus according to claim 1 , wherein based on a total mass of the positive electrode material layer, a percentage of the first positive electrode material is 80% to 98%.

8. The electrochemical apparatus according to claim 1 , wherein the second positive electrode material has a characteristic diffraction peak A in an X-ray diffraction pattern in a range of 15° to 16° and/or a characteristic diffraction peak B in a range of 18° to 19°, and a ratio of I A /I B of an intensity I A of the characteristic diffraction peak A to an intensity I B of the characteristic diffraction peak B satisfies 0<I A /I B ≤0.2.

9. The electrochemical apparatus according to claim 8 , wherein in the X-ray diffraction pattern of the second positive electrode material after a first cycle of charge, the characteristic diffraction peak A and the characteristic diffraction peak B both shift toward lower angles, with a shift magnitude less than 0.5°.

10. The electrochemical apparatus according to claim 1 , wherein the first positive electrode material comprises at least one of LifePO 4 , LiFe 0.5 Mn 0.5 PO 4 , Li 0.9 Fe 0.5 Mn 0.45 Ti 0.05 PO 4 , Li 0.9 Fe 0.5 Mn 0.45 Ti 0.04 Zr 0.01 PO 4 , or Li 0.95 FePO 3.95 F 0.05 ; and/or the second positive electrode material comprises at least one of LiMnO 2 , LiMn 0.9 Ni 0.1 O 2 , LiMn 0.9 Ni 0.05 Cr 0.05 O 2 , Li 0.95 MnO 1.95 F 0.05 , or Li 0.95 MnO 1.9 S 0.05 F 0.05 , (in g/cm 3 ); and Q is a numerical value representing a single-sided surface density of the positive electrode (in g/mm 2 ),
wherein Q is calculated according to Q=1540.25×m/Ar, where m is a numerical value representing a mass of the positive active material layer (in g), and Ar is a numerical value representing an area of the positive active material layer (in mm 2 ).

11. The electrochemical apparatus according to claim 1 , wherein the electrolyte comprises vinyl carbonate; wherein based on a total mass of the electrolyte, a percentage of the vinyl carbonate is 0.05% to 5%.

12. An electronic apparatus, comprising an electrochemical apparatus, the electrochemical apparatus comprises a positive electrode, a negative electrode, and an electrolyte, wherein
the positive electr

Assignees

• Ningde Amperex Technology Ltd

Inventors

• Zhou Molin

Classifications

• H01M2004/028

  Positive electrodes · CPC title

• H01M2004/021

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

• H01M10/0567

  characterised by the additives · CPC title

• H01M10/0525 Primary

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

• H01M4/5825

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