Abstract: A method and apparatus are described for monitoring a battery in an electronic device. In the described embodiments, a discharge current pulse is applied to a battery and the voltage change of the battery due to the discharge current pulse is determined. The impedance of the battery is then determined based on the voltage change and the discharge current pulse. An alert is then selectively generated based on the impedance.

Abstract: The disclosed embodiments relate to a battery cell which includes a weakness for relieving pressure. This battery cell includes a jelly roll comprising layers which are wound together, including a cathode with an active coating, a separator and an anode with an active coating. The jelly roll also includes a first conductive tab coupled to the cathode and a second conductive tab coupled to the anode. The jelly roll is enclosed in a flexible pouch, wherein the first and second conductive tabs extend through seals in the pouch to provide terminals for the battery cell. This pouch includes a weakness which yields when internal pressure in the pouch exceeds a threshold to create a hole which releases the internal pressure.

Abstract: The disclosed embodiments relate to the manufacture of a battery cell. The battery cell includes a set of layers including a cathode and an anode. The cathode includes a cathode substrate with a thickness in the range of 8-10 microns and a cathode active material. The anode includes an anode substrate with a thickness in the range of 4-6 microns and an anode active material. The cathode active material is coated on the cathode substrate at a rate of 2 mm/min to 3 mm/min, and the anode active material is coated on the anode substrate at a rate of 2 mm/min to 3.8 mm/min. Such substrate thicknesses and coating speeds may increase the energy density of the battery cell over that of a conventional battery cell with thicker cathode and anode substrates while avoiding manufacturing defects associated with the use of thinner substrates in battery cells.

Abstract: Some embodiments provide a system that monitors a battery in a portable electronic device. During operation, the system applies a pulse load to the battery and determines an impedance of the battery by measuring a voltage of the battery during the pulse load. Next, the system assesses a health of the battery based on the impedance. Finally, the system uses the assessed health to manage use of the battery in the portable electronic device.

Abstract: The disclosed embodiments relate to the design of a battery cell with multiple thicknesses. This battery cell includes a jelly roll enclosed in a pouch, wherein the jelly roll includes layers which are wound together, including a cathode with an active coating, a separator, and an anode with an active coating. The jelly roll also includes a first conductive tab coupled to the cathode and a second conductive tab coupled to the anode. The jelly roll is enclosed in a flexible pouch, and the first and second conductive tabs are extended through seals in the pouch to provide terminals for the battery cell. Furthermore, the battery cell has two or more thicknesses, wherein the different thicknesses are created by removing material from one or more of the layers before winding the layers together.

Abstract: Some embodiments provide a system that monitors a battery in a portable electronic device. During operation, the system applies a pulse load to the battery and determines an impedance of the battery by measuring a voltage of the battery during the pulse load. Next, the system assesses a health of the battery based on the impedance. Finally, the system uses the assessed health to manage use of the battery in the portable electronic device.

Abstract: The disclosed embodiments provide a system that manages use of a battery in a portable electronic device. During operation, the system monitors a cycle number of the battery during use of the battery with the portable electronic device, wherein the cycle number corresponds to a number of charge-discharge cycles of the battery. If the cycle number exceeds a first cycle number threshold, the system modifies a charging technique for the battery to manage swelling in the battery.

Abstract: The disclosed embodiments provide a system that manages use of a solid-state battery in a portable electronic device. During operation, the system monitors a temperature of the solid-state battery during use of the solid-state battery with the portable electronic device. Next, the system modifies a charging technique for the solid-state battery based on the monitored temperature to increase a capacity or a cycle life of the solid-state battery. To modify the charging technique based on the monitored temperature, the system may increase a charge rate of the solid-state battery if the temperature exceeds a first temperature threshold. On the other hand, the system may maintain the charge rate of the solid-state battery if the temperature does not exceed the first temperature threshold.

Abstract: The disclosed embodiments relate to techniques for facilitating thermal transfer in a portable electronic device. The portable electronic device includes a battery pack, which further includes a battery cell. The battery pack may supply power to a set of components in the portable electronic device. The portable electronic device also includes a heat dissipator composed of graphene. The heat dissipator may be in thermal contact with one or more of the components. The heat dissipator may also be disposed over a surface of the battery pack.

Abstract: The disclosed embodiments relate to the manufacture of a battery cell. The battery cell includes a set of layers including a cathode with an active coating, a separator, and an anode with an active coating. The battery cell also includes a pouch enclosing the layers, wherein the pouch is flexible. The layers may be wound to create a jelly roll prior to sealing the layers in the flexible pouch. A curve may also be formed in the battery cell by applying a pressure of at least 0.13 kilogram-force (kgf) per square millimeter to the layers using a set of curved plates applying a temperature of about 85° C. to the layers.

Abstract: The disclosed embodiments provide a battery cell. The battery cell includes a set of layers forming a non-rectangular shape, wherein the set of layers comprises a cathode with an active coating, a separator, and an anode with an active coating. The battery cell also includes a first conductive tab coupled to the cathode and a second conductive tab coupled to the anode. The layers are enclosed in a flexible pouch, and the first and second conductive tabs are extended through seals in the pouch to provide terminals for the battery cell. Furthermore, the non-rectangular shape is created by removing material from one or more of the layers.

Abstract: The disclosed embodiments provide a battery cell. The battery cell includes a cathode current collector containing graphene, a cathode active material, an electrolyte, an anode active material, and an anode current collector. The graphene may reduce the manufacturing cost and/or increase the energy density of the battery cell.

Abstract: The disclosed embodiments relate to the manufacture of a battery cell. The battery cell includes a set of layers including a cathode with an active coating, a separator, and an anode with an active coating. The battery cell also includes a pouch enclosing the layers, wherein the pouch is flexible. The layers may be wound to create a jelly roll prior to sealing the layers in the flexible pouch. The stiffness of the battery cell may be increased by applying a pressure of at least 0.13 kilogram-force (kgf) per square millimeter and a temperature of about 85° C. to the layers.

Abstract: Some embodiments provide a system that monitors a battery in a portable electronic device. During operation, the system applies a pulse load to the battery and determines an impedance of the battery by measuring a voltage of the battery during the pulse load. Next, the system assesses a health of the battery based on the impedance. Finally, the system uses the assessed health to manage use of the battery in the portable electronic device.

Abstract: The disclosed embodiments provide a system that manages use of a battery in a portable electronic device. During operation, the system uses a reference electrode in the battery to monitor an anode potential of an anode in the battery during charging of the battery in the portable electronic device. If the anode potential falls below an anode potential threshold, the system modifies a charging technique for the battery to extend a cycle life of the battery. For example, the system may reduce a charge current of the battery if the anode potential falls below the anode potential threshold to prevent degradation caused by a negative anode potential during charging of the battery.

Abstract: The disclosed embodiments provide a battery cell. The battery cell includes a jelly roll enclosed in a pouch, wherein the jelly roll includes layers which are wound together, including a cathode with an active coating, a separator, and an anode with an active coating. To create the pouch, a first cup and a second cup are formed in a flexible sheet of pouch material based on a terrace position in the battery cell that facilitates efficient use of space within a portable electronic device. The second cup is folded over the first cup, and a terrace seal is formed at the terrace position by sealing the jelly roll in the pouch along a rim of the first and second cups.

Abstract: The disclosed embodiments relate to the design of a battery cell with multiple thicknesses. This battery cell includes a jelly roll enclosed in a pouch, wherein the jelly roll includes layers which are wound together, including a cathode with an active coating, a separator, and an anode with an active coating. The jelly roll also includes a first conductive tab coupled to the cathode and a second conductive tab coupled to the anode. The jelly roll is enclosed in a flexible pouch, and the first and second conductive tabs are extended through seals in the pouch to provide terminals for the battery cell. Furthermore, the battery cell has two or more thicknesses, wherein the different thicknesses are created by removing material from one or more of the layers before winding the layers together.

Abstract: The disclosed embodiments provide a system that manages use of a battery in a portable electronic device. During operation, the system monitors a cycle number of the battery during use of the battery with the portable electronic device, wherein the cycle number corresponds to a number of charge-discharge cycles of the battery. If the cycle number exceeds a first cycle number threshold, the system modifies a charging technique for the battery to manage swelling in the battery.

Abstract: The disclosed embodiments provide a battery pack for use with a portable electronic device. The battery pack includes a first set of cells with different capacities electrically coupled in a parallel configuration. Cells within the first set of cells may also have different thicknesses and/or dimensions. The first set of cells is arranged within the battery pack to facilitate efficient use of space within a portable electronic device. For example, the first set of cells may be arranged to accommodate components in the portable electronic device.

Abstract: The disclosed embodiments provide a battery cell which includes a set of jelly rolls enclosed in a pouch. Each jelly roll includes layers which are wound together, including a cathode with an active coating, a separator, and an anode with an active coating. The battery cell also includes a first set of conductive tabs and a second set of conductive tabs. Each of the first set of conductive tabs is coupled to the cathode of one of the jelly rolls, and each of the second set of conductive tabs is coupled to the anode of one of the jelly rolls. At least one of the first set and one of the second set of conductive tabs extend through seals in the pouch to provide terminals for the battery cell.