Capacitance measurement system for battery cell

Patent metadata

Field	Value
Publication number	US-2026036639-A1
Application number	US-202418791506-A
Country	US
Kind code	A1
Filing date	Aug 1, 2024
Priority date	Aug 1, 2024
Publication date	Feb 5, 2026
Grant date	—

Abstract

Aspects of the disclosure include a system for monitoring a capacitance across a battery cell during electrolyte wetting and cell formation and methods of using the same. An exemplary system includes a battery cell, a first conductive plate positioned over a first end of the battery cell, and a second conductive plate positioned on a second end of the battery cell. The first conductive plate is separated from the first end of the battery cell by a gap and the second conductive plate includes a component of the battery cell. The second end of the battery cell is opposite the first end of the battery cell. The system includes a capacitance measurement system electrically coupled to the first conductive plate and the second conductive plate. The capacitance measurement system is configured to measure a capacitance across the first conductive plate and the second conductive plate.

First claim

What is claimed is:

1 . A system for monitoring a capacitance across a battery cell during electrolyte wetting and cell formation, the system comprising:
a battery cell; a first conductive plate positioned over a first end of the battery cell, the first conductive plate separated from the first end of the battery cell by a gap; a second conductive plate positioned on a second end of the battery cell, the second conductive plate comprising a component of the battery cell, the second end of the battery cell opposite the first end of the battery cell; and a capacitance measurement system electrically coupled to the first conductive plate and the second conductive plate, the capacitance measurement system configured to measure a capacitance across the first conductive plate and the second conductive plate.

2 . The system of claim 1 , wherein the capacitance measurement system is further configured to generate, during an electrolyte wetting process in which a liquid electrolyte is introduced into the battery cell, a capacitance-time curve.

3 . The system of claim 2 , wherein the capacitance measurement system is further configured to identify, in the capacitance-time curve, a first region dominated by a linearly decreasing capacitance over log time and a second region dominated by a linearly stable capacitance over log time.

4 . The system of claim 3 , wherein the capacitance measurement system is further configured to identify an improper wetting condition for the battery cell according to an absolute value of a capacitance of the battery cell within the second region.

5 . The system of claim 1 , wherein the capacitance measurement system is further configured to generate, during a formation cycling process for the battery cell, a capacitance-voltage curve.

6 . The system of claim 5 , wherein the capacitance measurement system is further configured to identify, in the capacitance-voltage curve, a first formation effect comprising an activation of an additive in the battery cell during the formation cycling process.

7 . The system of claim 6 , wherein identifying the first formation effect comprises identifying a destabilization of a capacitance measurement with a first increase in an incremental capacity of the battery cell.

8 . The system of claim 6 , wherein the capacitance measurement system is further configured to identify, in the capacitance-voltage curve, a second formation effect comprising phase changes in anode and cathode active materials due to intercalation and depletion of lithium ions, respectively.

9 . The system of claim 8 , wherein identifying the second formation effect comprises identifying a peak and subsequent drop in both a capacitance measurement and incremental capacity of the battery cell.

10 . The system of claim 8 , wherein the capacitance measurement system is further configured to identify, in the capacitance-voltage curve, a third formation effect comprising a completion of the formation cycling process as indicated by completion of several phase transitions in the anode and cathode active materials.

11 . A method for monitoring a capacitance across a battery cell during electrolyte wetting and cell formation, the method comprising:
providing a battery cell; positioning a first conductive plate over a first end of the battery cell, the first conductive plate separated from the first end of the battery cell by a gap; positioning a second conductive plate on a second end of the battery cell, the second conductive plate comprising a component of the battery cell, the second end of the battery cell opposite the first end of the battery cell; electrically coupling a capacitance measurement system to the first conductive plate and the second conductive plate; and measuring, with the capacitance measurement system, a capacitance across the first conductive plate and the second conductive plate during at least one of an electrolyte wetting process and a formation cycling process.

12 . The method of claim 11 , further comprising generating, during an electrolyte wetting process in which a liquid electrolyte is introduced into the battery cell, a capacitance-time curve.

13 . The method of claim 12 , further comprising identifying, in the capacitance-time curve, a first region dominated by a linearly decreasing capacitance over log time and a second region dominated by a linearly stable capacitance over log time.

14 . The method of claim 13 , further comprising identifying an improper wetting condition for the battery cell according to an absolute value of a capacitance of the battery cell within the second region.

15 . The method of claim 11 , further comprising generating, during a formation cycling process for the battery cell, a capacitance-voltage curve.

16 . The method of claim 15 , further comprising identifying, in the capacitance-voltage curve, a first formation effect comprising an activation of an additive in the battery cell during the formation cycling process.

17 . The method of claim 16 , wherein identifying the first formation effect comprises identifying a destabilization of a capacitance measurement with a first increase in an incremental capacity of the battery cell.

18 . The method of claim 16 , further comprising identifying, in the capacitance-voltage curve, a second formation effect comprising phase changes in anode and cathode active materials due to intercalation and depletion of lithium ions, respectively.

19 . The method of claim 18 , wherein identifying the second formation effect comprises identifying a peak and subsequent drop in both a capacitance measurement and incremental capacity of the battery cell.

20 . The method of claim 18 , further comprising identifying, in the capacitance-voltage curve, a third formation effect comprising a completion of the formation cycling process as indicated by completion of several phase transitions in the anode and cathode active materials.

Assignees

• Gm Global Tech Operations Llc

Inventors

• Schmidt Robert D
• Pieczonka Nicholas Paul William
• Salvador James R
• Taha Raneen
• Kim Brian
• Kukreja Ratandeep Singh
• Huemiller Erik Damon
• Xu Shaomao
• Sekol Ryan Curtis
• Balogh Michael P

Classifications

• H01M10/058

  Construction or manufacture · CPC title

• G01R31/3865 Primary

  related to manufacture, e.g. testing after manufacture · CPC title

• G01R31/382

  Arrangements for monitoring battery or accumulator variables, e.g. SoC · CPC title

• G01R31/389 Primary

  Measuring internal impedance, internal conductance or related variables · CPC title

• G01R31/378

  specially adapted for the type of battery or accumulator · CPC title