Method for estimating the self-discharge of a lithium battery

• US 9,608,456 B2
• Filed: 01/20/2012
• Issued: 03/28/2017
• Est. Priority Date: 01/20/2011
• Status: Active Grant

• Current Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Original Assignee: Commissariat a L'Energie Atomique (AES Corporation)
• Inventors: Martin, Nelly, Le Cras, Frederic
• Primary Examiner(s): Williams, Arun
• Application Number:
  US13/980,132
• Publication Number:
  US 20140049227A1
• Time in Patent Office: 1,894 Days
• Field of Search: 320/162
• US Class Current: 1/1
• CPC Class Codes: H01M 10/0525 Rocking-chair batteries, i.e. batteries with lithium insertion or intercalation in both electrodes; Lithium-ion batteries
• CPC Class Codes: H01M 10/4285 Testing apparatus
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/446 Initial charging measures
• CPC Class Codes: H01M 6/5088 Initial activation; predischarge; Stabilisation of initial voltage
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02P 70/50 Manufacturing or production processes characterised by the final manufactured product

Abstract

A method for determining the self-discharge current of a lithium-ion battery provided with a positive electrode, a negative electrode, and an electrolyte arranged between the positive and negative electrodes includes charging the battery until a metal lithium layer is formed between the electrolyte and the negative electrode, measuring the open-circuit voltage of the battery at two moments, and determining the self-discharge current from the variation of the voltage measured between the two moments.

Claims

1. A method for determining a self-discharge current comprising the steps of:

providing a lithium-ion battery provided with a positive electrode, a negative electrode comprising a lithium ion insertion material, and a solid type electrolyte arranged between the positive and negative electrodes, the lithium ion insertion material being in direct contact with the solid type electrolyte,

charging the lithium-ion battery until a metal lithium layer is formed between the solid type electrolyte and the negative electrode,

measuring the open-circuit voltage of the lithium-ion battery at two moments without connecting the battery between the two moments, and

determining the self-discharge current from the variation of the measured voltage between the two moments.

2. The method according to claim 1, wherein the positive electrode comprises a quantity of lithium greater than the quantity of lithium that the negative electrode is capable of inserting.

3. The method according to claim 1, wherein the charge parameters are selected to cause a flow of lithium ions greater than the maximum flow of lithium ions capable of diffusing within the negative electrode.

4. The method according to claim 1, wherein the negative electrode comprises a material having a lithium chemical diffusion coefficient smaller than 10⁻

9 cm²/s.

5. The method according to claim 1, wherein the negative electrode comprises a lithium ion insertion material selected from the group consisting of Si, Al, Ge, SnO, LiNiO₂, and indium lead oxide.

6. The method according to claim 1, comprising a full first charging step of the lithium-ion battery configured to saturate the lithium ion insertion material followed by an additional charging step configured to form the metal lithium layer.

7. The method according to claim 1, wherein voltage measurements between two moments are made while the potential of the negative electrode is set to 0.

8. The method according to claim 1, wherein voltage measurements between two moments are achieved when relaxation of Li+ concentration in the positive electrode is reached.

9. A method for determining the self-discharge current of a lithium-ion battery provided with a positive electrode, a negative electrode comprising a lithium ion insertion material, and a solid type electrolyte arranged between the positive and negative electrodes, comprising the steps of:

providing the lithium-ion battery provided with a positive electrode, a negative electrode comprising a lithium ion insertion material, and a solid type electrolyte arranged between the positive and negative electrodes, the lithium ion insertion material being in direct contact with the solid type electrolyte,

charging the lithium-ion battery so that a significant quantity of Li+ ions is transferred to the negative electrode during a short time period, until a metal lithium layer is formed between the solid type electrolyte and the negative electrode,

measuring the open-circuit voltage of the lithium-ion battery at two moments without connecting the battery between the two moments, and

determining the self-discharge current from the variation of the measured voltage between the two moments.

10. The method according to claim 9, wherein the positive electrode comprises a quantity of lithium greater than the quantity of lithium that the negative electrode is capable of inserting.

11. The method according to claim 9, wherein the charge parameters are selected to cause a flow of lithium ions greater than the maximum flow of lithium ions capable of diffusing within the negative electrode.

12. The method according to claim 9, wherein the negative electrode comprises a material having a lithium chemical diffusion coefficient smaller than 10⁻

9 cm²/s.

13. The method according to claim 9, wherein the negative electrode comprises a lithium ion insertion material selected from the group consisting of Si, Al, Ge, SnO, LiNiO₂ and indium lead oxide.

14. The method according to claim 9, comprising a full first charging step of the lithium-ion battery configured to saturate the lithium ion insertion material followed by an additional charging step configured to form the metal lithium layer.

15. The method according to claim 9, wherein voltage measurements between two moments are made while the potential of the negative electrode is set to 0.

16. The method according to claim 9, wherein voltage measurements between two moments are achieved when relaxation of Li+ concentration in the positive electrode is reached.