Patent Application
20160020621
The present disclosure relates to device power, and more particularly, to a battery system that leverages the benefits of both single cell battery systems and two-cell series battery systems.
As new wireless communication technology continues to emerge, so do the capabilities available in new mobile devices. Initially, mobile devices were limited to only conveying voice communications. However, mobile devices have evolved into multifaceted platforms that have become increasingly integrated into daily existence. For example, devices such as smart phones, tablet computers, etc. are now used to conduct a variety of activities that were previously limited to being performed in-person, via a wired Internet connection, etc. Examples of these activities may include, but are not limited to, interpersonal communications, business communications, personal or professional financial transactions, interactions with social media or professional networking resources, downloading, uploading and/or consumption of multimedia content, etc.
With an increased reliance on mobile platforms comes increased focus on the resources that allow mobile platforms to function. For example, good power performance may be an area of focus for users in the market to purchase a mobile device. A mobile device that offers all sorts of beneficial functionality may be useless if it always needs to be recharged. When considering a power solution for a mobile platform, designers are often forced to select an imperfect solution. For example, at least two possible configurations for mobile batteries include a single cell “1S” type battery or a dual cell “2S” battery including two cells coupled in series. Both solutions have advantages and disadvantages. For example, 1S cells have readily available power management integrated circuits (PMICs) and chipsets, compatible device equipment, charging equipment and do not require cell balancing. However, the emergence of new larger mobile devices (e.g., tablet computers) may require the integration of inefficient voltage boost technology. Alternatively, 2S batteries operate at higher voltage levels, and thus, can more readily meet the needs of larger and more-powerful devices. However, there are also a number of disadvantages to 2S batteries such as, for example, a lack of available power control solutions that necessitate inefficient kluges to make these batteries work with existing technology, more expensive chargers, cell balancing, etc.
Features and advantages of various embodiments of the claimed subject matter will become apparent as the following Detailed Description proceeds, and upon reference to the Drawings, wherein like numerals designate like parts, and in which:
Although the following Detailed Description will proceed with reference being made to illustrative embodiments, many alternatives, modifications and variations thereof will be apparent to those skilled in the art.
The present application is directed to a bidirectional voltage converter for multi-cell series batteries. In one embodiment, a power module in a device may comprise at least a battery including at least two cells and a converter module to generate a single-cell voltage and a two-cell series voltage based on energy provided by the battery cells while also controlling the charge and/or discharge of the cells to be at substantially the same rate. The converter module may comprise, for example, a first capacitor coupled across a first cell in the battery, a second capacitor coupled across a second cell in the battery and a third capacitor that may be flexibly coupled across either the first capacitor or the second capacitor based on the manipulation of transistor switches also in the power module. When balancing charge and/or discharge rate, the third capacitor may be coupled across the second capacitor for a set on time to charge the third capacitor, and then coupled across the first capacitor for the set on time. A variable off time between couplings may be determined based on the difference between the voltage in the third capacitor and first capacitor. Embodiments consistent with the present disclosure may also include a power monitoring module for determining battery charge.
In one embodiment, a power module for providing power to a device may comprise, for example, at least a battery and a converter module. The battery may include at least two battery cells coupled in series. The converter module may be coupled to at least the battery and may be to generate at least a single-cell voltage and a two-cell series voltage from the battery while controlling at least one of charging or discharging of the at least two battery cells to be at substantially the same rate.
In one embodiment, the at least two battery cells may comprise a first battery cell to provide energy for generating the single-cell voltage and a second battery cell to, combined with the first battery, provide energy for generating the two-cell series voltage. The converter module may comprise, for example, a first capacitor coupled across the first battery cell, a second capacitor coupled across the second battery cell and a third capacitor flexibly coupled across either the first capacitor or second capacitor, the coupling of the third capacitor being based on control circuitry in the converter module. The control circuitry may comprise, for example, at least one drive and control module to drive at least four transistor switches, the at least four transistor switches being configurable by the at least one drive and control module to cause the third capacitor to be coupled across the first capacitor, coupled across the second capacitor or coupled to ground. The at least four transistor switches may include at least one of n-channel or p-channel metal oxide semiconductor field effect transistors. The at least one drive and control module may be to, for example, cause the third capacitor to be coupled across the second capacitor for a fixed on time to charge the third capacitor, determine a variable off time, delay for the variable off time and cause the third capacitor to be coupled across the first capacitor for the fixed on time. In one embodiment, the third capacitor may be to convey charge from the second capacitor to the first capacitor to supplement current being provided by the first battery cell to loads being driven by the single-cell voltage. In another embodiment, the third capacitor may be to convey charge from the first capacitor to the second capacitor, the charge being provided from a charging module configured to provide a charging current based on the single-cell voltage. The at least one drive and control module being to determine a variable off time may comprise, for example, the at least one drive and control module being to cause the third capacitor to be coupled to a common ground with the first capacitor, determine a voltage of the first capacitor, determine a voltage for the third capacitor, determine a difference between the first capacitor voltage and the third capacitor voltage and determine the variable off time based on an inverse of an absolute value of the difference between the first capacitor voltage and the third capacitor voltage.
In the same or a different embodiment, the power module may further comprise at least one direct current to direct current converter module to convert the two-cell series voltage into at least one higher or lower voltage. The power module may further comprise, for example, at least one power management module to convert the single-cell voltage to at least one higher or lower voltage. The power module may further comprise, for example, a power monitoring module including at least a fuel gauge module and a resistor network having at least a first resistor and second resistor. The fuel gauge module may be to measure current being provided to single-cell voltage loads through the first resistor, measure current being provided to two-cell series voltage loads through the first and second resistors, determine at least one of average charge current or discharge current based on the measurement and generate at least one of charge level data or interrupts based on the current determination. An example method consistent with the present disclosure may comprise causing, in a converter module comprising at least a first capacitor coupled across a first battery cell, a second capacitor coupled across a second battery cell and a third capacitor flexibly coupled across at least the first capacitor or the second capacitor, the third capacitor to be coupled across the second capacitor for a fixed on time to charge the third capacitor, determining a variable off time, delaying for the variable off time and causing the third capacitor to be coupled across the first capacitor for the fixed on time.
Power module 102 may include, for example, at least battery 108, bidirectional 1S to 2S converter module (1S/2SCM) 110, charging module 112 and a variety of modules 114-120 for generating different levels of voltage for supporting operational equipment 106 in device 100. In at least one embodiment, battery 108 may be a 2S battery comprising two cells coupled in series. While battery 108 has been disclosed herein as comprising only two cells, the use of a 2S battery herein is merely for the sake of explanation. Consistent with the present disclosure, battery 108 may comprise more than two cells based on, for example, the type, configuration, etc. of device 100. Returning to the example disclosed in
Consistent with the present disclosure, some or all of the above challenges to 2S battery use may be eliminated. 1S/2SCM 110 may be capable of generating both a 2S voltage (e.g., 6V to 8.7V) and a single cell (1S) voltage (e.g., 3V to 4.35V), and thus, may utilize existing PMICs configured to run on 1S voltage, may be charged by 1S battery chargers configured to integrate with existing USB technology, may automatically keep the cells balanced by balancing charge and/or discharge rate, etc. For example, charging interface 104 may receive power from a power source external to device 100 and may provide this power to charging module 112 that may proceed to generate a 1S voltage to 1S/2SCM 110. 1S/2SCM 110 may utilize the 1S voltage to equally charge both cells in battery 108. As further disclosed in
Device 100′ may comprise, for example, system module 200 configured to manage device operations. System module 200 may include, for example, processing module 202, memory module 204, power module 102′, user interface module 206 and communication interface module 208. Device 100′ may also include communication module 210 (e.g., with which charging interface 104′ may be associated). While communication module 210 has been illustrated as separate from system module 200, the example implementation shown in
In device 100′, processing module 202 may comprise one or more processors situated in separate components, or alternatively, one or more processing cores embodied in a single component (e.g., in a System-on-a-Chip (SoC) configuration) and any processor-related support circuitry (e.g., bridging interfaces, etc.). Example processors may include, but are not limited to, various x86-based microprocessors available from the Intel Corporation including those in the Pentium, Xeon, Itanium, Celeron, Atom, Core i-series product families, Advanced RISC (e.g., Reduced Instruction Set Computing) Machine or “ARM” processors, etc. Examples of support circuitry may include chipsets (e.g., Northbridge, Southbridge, etc. available from the Intel
Corporation) configured to provide an interface through which processing module 202 may interact with other system components that may be operating at different speeds, on different buses, etc. in device 100′. Some or all of the functionality commonly associated with the support circuitry may also be included in the same physical package as the processor (e.g., such as in the Sandy Bridge family of processors available from the Intel Corporation).
Processing module 202 may be configured to execute various instructions in device 100′. Instructions may include program code configured to cause processing module 202 to perform activities related to reading data, writing data, processing data, formulating data, converting data, transforming data, etc. Information (e.g., instructions, data, etc.) may be stored in memory module 204. Memory module 204 may comprise random access memory (RAM) and/or read-only memory (ROM) in a fixed or removable format. RAM may include volatile memory configured to hold information during the operation of device 100′ such as, for example, static RAM (SRAM) or Dynamic RAM (DRAM). ROM may include non-volatile (NV) memory modules configured based on BIOS, UEFI, etc. to provide instructions when device 100′ is activated, programmable memories such as electronic programmable ROMs (EPROMS), Flash, etc. Other fixed/removable memory may include, but are not limited to, magnetic memories such as, for example, floppy disks, hard drives, etc., electronic memories such as solid state flash memory (e.g., embedded multimedia card (eMMC), etc.), removable memory cards or sticks (e.g., micro storage device (uSD), USB, etc.), optical memories such as compact disc-based ROM (CD-ROM), Digital Video Disks (DVD), Blu-Ray Disks, etc.
User interface module 206 may include hardware and/or software to allow users to interact with device 100′ such as, for example, various input mechanisms (e.g., microphones, switches, buttons, knobs, keyboards, speakers, touch-sensitive surfaces, one or more sensors configured to capture images and/or sense proximity, distance, motion, gestures, orientation, etc.) and various output mechanisms (e.g., speakers, displays, lighted/flashing indicators, electromechanical components for vibration, motion, etc.). The hardware in user interface module 206 may be incorporated within device 100′ and/or may be coupled to device 100′ via a wired or wireless communication medium. Communication interface module 208 may be configured to manage packet routing and other control functions for communication module 210, which may include resources configured to support wired and/or wireless communications. In some instances, device 100′ may comprise more than one communication module 210 (e.g., including separate physical interface modules for wired protocols and/or wireless radios) all managed by a centralized communication interface module 210. Wired communications may include serial and parallel wired mediums such as, for example, Ethernet, USB, Firewire, Digital Video Interface (DVI), High-Definition Multimedia Interface (HDMI), etc. Wireless communications may include, for example, close-proximity wireless mediums (e.g., radio frequency (RF) such as based on the Near Field Communications (NFC) standard, infrared (IR), etc.), short-range wireless mediums (e.g., Bluetooth, WLAN, Wi-Fi, etc.), long range wireless mediums (e.g., cellular wide-area radio communication technology, satellite-based communications, etc.) or electronic communications via sound waves. In one embodiment, communication interface module 208 may be configured to prevent wireless communications that are active in communication module 210 from interfering with each other. In performing this function, communication interface module 208 may schedule activities for communication module 210 based on, for example, the relative priority of messages awaiting transmission. While the embodiment disclosed in
Power module 102′ may be configured to receive power via charging interface 104′ and to then supply power for modules 200-210. In one embodiment, charging interface 104′ may be associated with communication module 210 because power may be received via a USB interface typically associated with conveying data. Since modules 200 to 210 may incorporate different types of technology, each module 200 to 210 may need to be supplied with one or more different operational voltages. For example, low power technologies may require 3.3V rails, while other components may require traditional 5V logic levels. Components in user interface module 106 may, for example, require 18-20V levels to power displays, backlights, etc. Again the variety of voltages needed in device 100′ may depend on, for example, the device type (e.g., smartphone, tablet computer, netbook, laptop, NUC, etc.), the functionality incorporated in device 100′, etc.
1S/2SCM 110′ may comprise, for example, at least capacitors C1, C2 and C3, at least one drive and control module (DCM) 302 (e.g., in the disclosed embodiment, separate DCMs 302A and 302B are shown) and transistor switches Q1, Q2, Q3 and Q4 (collectively, “transistors Q1-Q4”). In one embodiment, transistors Q1-Q4 may be n-channel or p-channel metal oxide semiconductor field effect transistors (MOSFETS). In general, capacitors C1 and C2 may reflect the charge in CELL1 and CELL2, respectively, and capacitor C3 may act as a charge reservoir that “moves” between capacitors C1 and C2 to supplement the current being provided to 1S and 2S loads. The “moving” described above may involve DCM 302A and/or 302B causing transistors Q1-Q4 to couple capacitor C3 across capacitor C1, across capacitor C2, to ground, etc. Initially, capacitor C3 may be uncoupled when transistors Q1-Q4 are all off. DCM 302A and/or 302B may cause capacitor C3 to be coupled across capacitor C2 by turning on only transistors Q4 and Q2. DCM 302A and/or 302B may cause capacitor C3 to be coupled to ground by turning on only transistor Q1. DCM 302A and/or 302B may cause capacitor C3 to be coupled across capacitor C1 by turning on only transistors Q3 and Q1.
At least one benefit of 1S/2SCM 110′ is that it is bidirectional. During normal operation, charge may be transferred from CELL2 to CELL1 via capacitor C3 moving between capacitors C2 and C1 to supplement current provided by CELL1 to support 1S loads. Supplementing the 1S current in this manner may equalize the discharge rate of the CELL1 and CELL2. Moreover, further to utilizing a battery charger that may provide a 2S voltage to charge battery 108′, which may be a more expensive solution from the standpoint of the higher cost of the charger, the need for a dedicated charging port, etc., it now also becomes possible to use cheaper and more readily available 1S-type battery chargers. Capacitor C3 may convey charge from CELL1 to CELL2 in instances where, for example, charging module 112 provides a 1S charging current to CELL1. Consistent with the present disclosure, the configuration of 1S/2SCM 110′ allows charging and discharging to be done from the 1S and 2S voltage terminals simultaneously and independently.
Following delaying for the off time in operation 410, DCM 302A and/or 302B may cause capacitor C3 to be coupled across capacitor C1 by turning on transistor Q3 (e.g., while transistor Q1 remains on) in operation 412. In one mode of operation, the coupling of capacitor C3 across capacitor C1 may supplement the current being provided by CELL1 to support load being driven by the 1S voltage using stored charge provided by CELL2. The coupling of capacitor C3 across capacitor C1 may remain for the duration of the on time in operation 414. Transistors Q1 and Q3 may then be turned off in operation 416, totally decoupling capacitor C3 from capacitor C1, capacitor C2 and ground. Consistent with the present disclosure, operation 416 may be followed by a return to operation 400 wherein operations 400 to 416 may resume with capacitor C3 again being coupled across capacitor C2. In an alternative mode of operation, this second coupling of capacitor C3 across capacitor C2 may convey stored charge from CELL1 to CELL2 when, for example, a charging current is being provided to the 1S terminal of CELL 1 by charging 112.
While
As used in this application and in the claims, a list of items joined by the term “and/or” can mean any combination of the listed items. For example, the phrase “A, B and/or C” can mean A; B; C; A and B; A and C; B and C; or A, B and C. As used in this application and in the claims, a list of items joined by the term “at least one of” can mean any combination of the listed terms. For example, the phrases “at least one of A, B or C” can mean A; B; C; A and B; A and
C; B and C; or A, B and C.
As used in any embodiment herein, the term “module” may refer to software, firmware and/or circuitry configured to perform any of the aforementioned operations. Software may be embodied as a software package, code, instructions, instruction sets and/or data recorded on non-transitory computer readable storage mediums. Firmware may be embodied as code, instructions or instruction sets and/or data that are hard-coded (e.g., nonvolatile) in memory devices. “Circuitry”, as used in any embodiment herein, may comprise, for example, singly or in any combination, hardwired circuitry, programmable circuitry such as computer processors comprising one or more individual instruction processing cores, state machine circuitry, and/or firmware that stores instructions executed by programmable circuitry. The modules may, collectively or individually, be embodied as circuitry that forms part of a larger system, for example, an integrated circuit (IC), system on-chip (SoC), desktop computers, laptop computers, tablet computers, servers, smartphones, etc.
Any of the operations described herein may be implemented in a system that includes one or more storage mediums (e.g., non-transitory storage mediums) having stored thereon, individually or in combination, instructions that when executed by one or more processors perform the methods. Here, the processor may include, for example, a server CPU, a mobile device CPU, and/or other programmable circuitry. Also, it is intended that operations described herein may be distributed across a plurality of physical devices, such as processing structures at more than one different physical location. The storage medium may include any type of tangible medium, for example, any type of disk including hard disks, floppy disks, optical disks, compact disk read-only memories (CD-ROMs), compact disk rewritables (CD-RWs), and magneto-optical disks, semiconductor devices such as read-only memories (ROMs), random access memories (RAMs) such as dynamic and static RAMs, erasable programmable read-only memories (EPROMs), electrically erasable programmable read-only memories (EEPROMs), flash memories, Solid State Disks (SSDs), embedded multimedia cards (eMMCs), secure digital input/output (SDIO) cards, magnetic or optical cards, or any type of media suitable for storing electronic instructions. Other embodiments may be implemented as software modules executed by a programmable control device.
Thus, the present application is directed to a bidirectional voltage converter for multi-cell series batteries. A power module may comprise a battery including at least two cells and a converter module to generate a single-cell voltage and a two-cell series voltage from battery power while controlling charging and/or discharging of the cells to be at substantially the same rate. A converter module may comprise a first capacitor coupled across a first cell, a second capacitor coupled across a second cell and a third capacitor that may be flexibly coupled. When balancing charge and/or discharge rate, the third capacitor may be coupled across the second capacitor for a set on time and then coupled across the first capacitor for the set on time. A variable off time between couplings may be determined based on the difference between the voltage in the third capacitor and first capacitor.
The following examples pertain to further embodiments. The following examples of the present disclosure may comprise subject material such as a device, a method, at least one machine-readable medium for storing instructions that when executed cause a machine to perform acts based on the method, means for performing acts based on the method and/or a system for bidirectional voltage converter for multi-cell series batteries, as provided below.
According to example 1 there is provided a power module for providing power to a device. The device may comprise a battery including at least two battery cells coupled in series and a converter module coupled to at least the battery, the converter module being to generate at least a single-cell voltage and a two-cell series voltage from the battery while controlling at least one of charging or discharging of the at least two battery cells to be at substantially the same rate.
Example 2 may include the elements of example 1, wherein, wherein the at least two battery cells comprise a first battery cell to provide energy for generating the single-cell voltage and a second battery cell to, combined with the first battery, provide energy for generating the two-cell series voltage.
Example 3 may include the elements of example 2, wherein at least one of the first battery cell and the second battery cell comprise protection circuitry.
Example 4 may include the elements of any of examples 1 to 3, wherein the converter module comprises a first capacitor coupled across the first battery cell, a second capacitor coupled across the second battery cell and a third capacitor flexibly coupled across either the first capacitor or second capacitor, the coupling of the third capacitor being based on control circuitry in the converter module.
Example 5 may include the elements of example 4, wherein the control circuitry comprises at least one drive and control module to drive at least four transistor switches, the at least four transistor switches being configurable by the at least one drive and control module to cause the third capacitor to be coupled across the first capacitor, coupled across the second capacitor or coupled to ground.
Example 6 may include the elements of example 5, wherein the at least four transistor switches include at least one of n-channel or p-channel metal oxide semiconductor field effect transistors.
Example 7 may include the elements of example 5, wherein the at least one drive and control module is to cause the third capacitor to be coupled across the second capacitor for a fixed on time, determine a variable off time, delay for the variable off time and cause the third capacitor to be coupled across the first capacitor for the fixed on time.
Example 8 may include the elements of example 7, wherein the third capacitor is to convey charge from the second capacitor to the first capacitor to supplement current being provided by the first battery cell to loads being driven by the single-cell voltage.
Example 9 may include the elements of example 7, wherein the third capacitor is to convey charge from the first capacitor to the second capacitor, the charge being provided from a charging module configured to provide a charging current based on the single-cell voltage.
Example 10 may include the elements of example 9, wherein the charging module receives power from a charging interface to generate a single cell voltage to charge at least the first battery cell.
Example 11 may include the elements of example 10, wherein the charging interface is also a communication interface.
Example 12 may include the elements of example 7, wherein the at least one drive and control module being to determine a variable off time comprises the at least one drive and control module being to cause the third capacitor to be coupled to a common ground with the first capacitor, determine a voltage of the first capacitor, determine a voltage for the third capacitor, determine a difference between the first capacitor voltage and the third capacitor voltage and determine the variable off time based on an inverse of an absolute value of the difference between the first capacitor voltage and the third capacitor voltage.
Example 13 may include the elements of example 12, wherein the at least one drive and control module is further to determine the fixed on time based on at least one of the maximum average current required between the two-cell series voltage and the single-cell voltage or a selected maximum switching frequency for moving the third capacitor between the first and second capacitors.
Example 14 may include the elements of any of examples 1 to 3, further comprising at least one direct current to direct current converter module to convert the two-cell series voltage into at least one higher or lower voltage.
Example 15 may include the elements of example 14, further comprising at least one power management module to convert the single-cell voltage to at least one higher or lower voltage.
Example 16 may include the elements of example 15, wherein at least one of the at least one direct current to direct current converter or the at least one power management module are to generate voltages for driving operational equipment in the device comprising the power module. Example 17 may include the elements of any of examples 1 to 3, further comprising a power monitoring module including at least a fuel gauge module and a resistor network having at least a first resistor and second resistor.
Example 18 may include the elements of example 17, wherein the fuel gauge module is to measure current being provided to single-cell voltage loads through the first resistor, measure current being provided to two-cell series voltage loads through the first and second resistors, determine at least one of average charge current or discharge current based on the measurement and generate at least one of charge level data or interrupts based on the current determination.
Example 19 may include the elements of any of examples 1 to 3, wherein the at least two battery cells comprise a first battery cell to provide energy for generating the single-cell voltage and a second battery cell to, combined with the first battery, provide energy for generating the two-cell series voltage, and the converter module comprises a first capacitor coupled across the first battery cell, a second capacitor coupled across the second battery cell and a third capacitor flexibly coupled across either the first capacitor or second capacitor, the coupling of the third capacitor being based on control circuitry in the converter module.
Example 20 may include the elements of any of examples 1 to 3, further comprising a power monitoring module including at least a fuel gauge module and a resistor network having at least a first resistor and second resistor, the fuel gauge module being to measure current being provided to single-cell voltage loads through the first resistor, measure current being provided to two-cell series voltage loads through the first and second resistors, determine at least one of average charge current or discharge current based on the measurement and generate at least one of charge level data or interrupts based on the current determination.
According to example 21 there is provided a method for controlling at least one of battery cell charge or discharge. The method may comprise causing, in a converter module comprising at least a first capacitor coupled across a first battery cell, a second capacitor coupled across a second battery cell and a third capacitor flexibly coupled across at least the first capacitor or the second capacitor, the third capacitor to be coupled across the second capacitor for a fixed on time to charge the third capacitor, determining a variable off time, delaying for the variable off time and causing the third capacitor to be coupled across the first capacitor for the fixed on time.
Example 22 may include the elements of example 21, wherein the third capacitor is conveying charge from the second capacitor to the first capacitor to supplement current being provided by the first battery cell to loads being driven by the single-cell voltage.
Example 23 may include the elements of any of examples 21 to 22, wherein the third capacitor is conveying charge from the first capacitor to the second capacitor, the charge being provided from a charging module configured to provide a charging current based on the single-cell voltage.
Example 24 may include the elements of any of examples 21 to 22, wherein determining a variable off time comprises causing the third capacitor to be coupled to a common ground with the first capacitor, determining a voltage of the first capacitor, determining a voltage for the third capacitor, determining a difference between the first capacitor voltage and the third capacitor voltage and determining the variable off time based on an inverse of an absolute value of the difference between the first capacitor voltage and the third capacitor voltage.
Example 25 may include the elements of example 24, and may further comprise determining the fixed on time based on at least one of the maximum average current required between the two-cell series voltage and the single-cell voltage or a selected maximum switching frequency for moving the third capacitor between the first and second capacitors.
Example 26 may include the elements of any of examples 21 to 22, and may further comprise measuring, in a power monitoring module including at least a fuel gauge module and a resistor network having at least a first resistor and second resistor, current being provided to single-cell voltage loads through the first resistor, measuring current being provided to two-cell series voltage loads through the first and second resistors, determining at least one of average charge current or discharge current based on the measurement and generating at least one of charge level data or interrupts based on the current determination.
According to example 27 there is provided a system including at least a device, the system being arranged to perform the method of any of the above examples 21 to 26.
According to example 28 there is provided a chipset arranged to perform the method of any of the above examples 21 to 26.
According to example 29 there is provided at least one machine readable medium comprising a plurality of instructions that, in response to be being executed on a computing device, cause the computing device to carry out the method according to any of the above examples 21 to 26.
According to example 30 there is provided a device configured with a bidirectional voltage converter for multi-cell series batteries, the device being arranged to perform the method of any of the above examples 21 to 26.
According to example 31 there is provided a system for controlling at least one of battery cell charge or discharge. The system may comprise means for causing, in a converter module comprising at least a first capacitor coupled across a first battery cell, a second capacitor coupled across a second battery cell and a third capacitor flexibly coupled across at least the first capacitor or the second capacitor, the third capacitor to be coupled across the second capacitor for a fixed on time to charge the third capacitor, means for determining a variable off time, means for delaying for the variable off time and means for causing the third capacitor to be coupled across the first capacitor for the fixed on time.
Example 32 may include the elements of example 31, wherein the third capacitor is conveying charge from the second capacitor to the first capacitor to supplement current being provided by the first battery cell to loads being driven by the single-cell voltage.
Example 33 may include the elements of any of examples 31 to 32, wherein the third capacitor is conveying charge from the first capacitor to the second capacitor, the charge being provided from a charging module configured to provide a charging current based on the single-cell voltage.
Example 34 may include the elements of any of examples 31 to 32, wherein the means for determining a variable off time comprise means for causing the third capacitor to be coupled to a common ground with the first capacitor, means for determining a voltage of the first capacitor, means for determining a voltage for the third capacitor, means for determining a difference between the first capacitor voltage and the third capacitor voltage and means for determining the variable off time based on an inverse of an absolute value of the difference between the first capacitor voltage and the third capacitor voltage.
Example 35 may include the elements of any of examples 31 to 32, and may further comprise means for measuring, in a power monitoring module including at least a fuel gauge module and a resistor network having at least a first resistor and second resistor, current being provided to single-cell voltage loads through the first resistor, means for measuring current being provided to two-cell series voltage loads through the first and second resistors, means for determining at least one of average charge current or discharge current based on the measurement and means for generating at least one of charge level data or interrupts based on the current determination.
The terms and expressions which have been employed herein are used as terms of description and not of limitation, and there is no intention, in the use of such terms and expressions, of excluding any equivalents of the features shown and described (or portions thereof), and it is recognized that various modifications are possible within the scope of the claims. Accordingly, the claims are intended to cover all such equivalents.
