Battery cell with an integrated pouch metal foil terminal

• US 9,136,509 B2
• Filed: 05/27/2011
• Issued: 09/15/2015
• Est. Priority Date: 05/27/2011
• Status: Active Grant

• Current Assignee: Apple Inc.
• Original Assignee: Apple Inc.
• Inventors: Tam, Ching Yu John, Birrell, Craig C.
• Primary Examiner(s): Rodas, Richard Isla
• Assistant Examiner(s): DIBENEDETTO, MICHAEL N
• Application Number:
  US13/118,025
• Publication Number:
  US 20120299555A1
• Time in Patent Office: 1,572 Days
• Field of Search: 429/61, 429/79, 429/90, 429/91, 429/179, 324/433, 324/434, 324/435, 324/426, 324/500, 324/509, 324/512, 324/522, 361/42, 361/78, 361/79, 361/86, 361/88, 702 57- 65, 320/112, 320/113
• US Class Current: 1/1
• CPC Class Codes: H01M 10/44 Methods for charging or discharging circuits for charging H02J7/00
• CPC Class Codes: H01M 10/46 Accumulators structurally combined with charging apparatus circuits for charging H02J7/00
• CPC Class Codes: H01M 10/48 Accumulators combined with arrangements for measuring, testing or indicating the condition of cells, e.g. the level or density of the electrolyte constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals, H01M50/569
• CPC Class Codes: H01M 2010/4271 Battery management systems including electronic circuits, e.g. control of current or voltage to keep battery in healthy state, cell balancing
• CPC Class Codes: H01M 50/119 Metals
• CPC Class Codes: H01M 50/1243 characterised by the internal coating on the casing
• CPC Class Codes: H01M 50/141 for protecting against humidity
• CPC Class Codes: H01M 50/55 on the same side of the cell
• CPC Class Codes: H01M 50/557 Plate-shaped terminals
• CPC Class Codes: H01M 50/569 Constructional details of current conducting connections for detecting conditions inside cells or batteries, e.g. details of voltage sensing terminals battery terminal connectors with integrated measuring arrangements G01R31/364
• CPC Class Codes: H02J 7/0071 with a programmable schedule
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• 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 battery includes a battery cell having a pair of cell electrodes that are encased in a laminated pouch. The laminated pouch has a conductive moisture barrier layer that is sandwiched between respective electrically insulating layers. Several terminals are integrated with the pouch, including a first terminal and a second terminal that are directly connected to the first and second cell electrodes, respectively, and a third terminal that is directly connected to the conductive moister barrier layer. Other embodiments are also described and claimed.

Claims

1. An automated method for charging a rechargeable battery that is encased in a pouch having a conductive moisture barrier layer made of electrically insulated metal foil, the method comprising:

while charging the battery through first and second power terminals that are directly connected to battery cell electrodes, respectively, and are integrated with the pouch, applying a predetermined current to the metal foil, through a third terminal that is directly connected to the metal foil, while sensing a voltage of the metal foil through the third terminal, wherein the applied current is sourced from a power terminal of the battery;

comparing the sensed voltage to a threshold; and

based on the comparison, preventing the battery from being charged.

2. The method of claim 1, wherein the sensed voltage is relative to a voltage of the power terminal of the battery.

3. The method of claim 1 further comprising, while sensing the voltage of the metal foil and comparing the sensed voltage to the threshold:

driving the metal foil with a predetermined dc voltage for a predetermined duration;

then

releasing the metal foil from the predetermined voltage.

4. An automated method for charging a rechargeable battery that is encased in a pouch having a conductive moisture barrier layer made of electrically insulated metal foil, the method comprising:

while charging the battery through first and second power terminals that are directly connected to battery cell electrodes, respectively, and are integrated with the pouch, sensing voltage of the metal foil while driving the metal foil with a predetermined ac voltage source through a third terminal that is directly connected to the metal foil;

filtering the sensed voltage to measure frequency-dependent load that is presented to the ac voltage source;

comparing the measured frequency-dependent load to an expected range; and

based on the comparison, allowing the battery to be charged.

5. A battery comprising;

a battery cell having first and second cell electrodes encased in a laminated pouch, the laminated pouch having a conductive moisture barrier layer that is sandwiched between respective electrically insulating layers; and

a plurality of electrical terminals integrated with the pouch, including a first terminal and a second terminal that are directly connected to the first and second cell electrodes, respectively, and a third terminal that is directly connected to the conductive moisture barrier layer.

6. The battery of claim 5 wherein the plurality of terminals emerge from the pouch in regions that are sealed off against leakage of an electrochemical compound of the cell.

7. The battery of claim 5 wherein the third terminal is a tongue extension of the conductive moisture barrier layer.

8. The battery of claim 5 further comprising:

a monitoring circuit integrated with the battery cell to monitor an operating parameter of the battery, the monitoring circuit being further coupled to the conductive moisture barrier layer of the pouch to sense voltage of the conductive moisture barrier layer.

9. The battery of claim 5 further comprising:

a monitoring circuit integrated with the battery cell to monitor a voltage of the battery, the monitoring circuit being further coupled to the conductive moisture barrier layer of the pouch to indicate the degree to which the conductive moisture barrier layer is biased.

10. The battery of claim 6 further comprising:

a monitoring circuit integrated with the battery cell to monitor a voltage of the battery, the monitoring circuit being further coupled to the conductive moisture barrier layer of the pouch to indicate the degree to which the conductive moisture barrier layer is biased.

11. The battery of claim 9 wherein the monitoring circuit is to simultaneously a) apply a predetermined current to the conductive moisture barrier layer, and b) compare voltage of the conductive moisture barrier layer to a predetermined threshold.

12. The battery of claim 11 wherein the applied current is sourced from a power terminal of the battery.

13. The battery of claim 9 wherein the monitoring circuit is powered through the first and second terminals of the battery.

14. The battery of claim 9 wherein the monitoring circuit comprises:

a comparator having a first input coupled to the conductive moisture barrier layer and a second input coupled to a threshold voltage;

a dc voltage source at a predetermined voltage; and

a switch that couples the dc voltage source to the conductive moisture barrier layer.

15. The battery of claim 9 wherein the monitoring circuit comprises:

an ac signal source capacitively coupled to the conductive moisture barrier layer;

an analog to digital converter, adc, capacitively coupled to the conductive moisture barrier layer; and

a digital filter having an input coupled to an output of the adc, to measure load that is being presented to the ac signal source.

16. An apparatus comprising:

a mobile device having a housing in which are integrated a battery having first and second power terminals that are directly connected to battery cell electrodes, respectively, and a bias detector, the battery having a metal foil cell pouch that has a conductive moisture barrier layer being a metal foil which is sandwiched between electrically insulating layers of the pouch, wherein the bias detector is to sense voltage of the metal foil cell pouch through a third terminal that is directly connected to the metal foil, the mobile device to analyze the sensed voltage and in response signal a battery fault,

wherein the bias detector comprises;

an ac signal source capacitively coupled to the metal foil cell pouch; and

an analog to digital converter capacitively coupled to the metal foil cell pouch to digitize the sensed voltage.

17. The apparatus of claim 16 wherein the bias detector is integrated within a case of the battery.

18. The apparatus of claim 16

wherein the apparatus further comprises a battery charger circuit inside the mobile device housing, and wherein the bias detector is installed on the same printed circuit carrier as the battery charger circuit.

19. The apparatus of claim 16 wherein the mobile device housing ha integrated therein a battery charging circuit that alters a charge procedure of the battery in response to the signaled battery fault.

20. The apparatus of claim 19 wherein the bias detector is to detect that the metal foil cell pouch is not biased by making a comparison of the sensed voltage to a predetermined threshold, and wherein the battery charging circuit in response maintains unchanged a charge procedure of the battery.

21. The apparatus of claim 16, wherein the mobile device is to analyze the digitized sensed voltage to measure frequency dependent impedance presented to the ac signal source.

22. An automated method for charging a rechargeable battery through first and second power terminals, wherein the battery is encased in a pouch having a conductive moisture barrier layer made of electrically insulated metal foil and a third terminal that is directly connected to the metal foil, the method comprising:

driving the metal foil through the third terminal with a predetermined dc voltage source for a predetermined duration;

releasing the metal foil from the predetermined voltage source after the predetermined duration;

sensing a voltage of the metal foil through the third terminal after the predetermined duration;

comparing the sensed voltage to a threshold; and

based on the comparison, preventing the battery from being charged through the first or second power terminals.

23. The method of claim 22, wherein the predetermined dc voltage source is sourced from a power terminal of the battery.

24. The method of claim 23, wherein the sensed voltage is relative to a voltage of the power terminal of the battery.