Systems, devices and methods for pulse charging and pulse heating of rechargeable energy sources - Patents.com

Abstract

Embodiments are disclosed that provide advanced charging of an array of energy sources for energy storage applications. Embodiments may include application of pulses to the energy sources for charging and preheating purposes. Systems and techniques for evaluating impedance, inductance, and thermal property parameters for use in heating and charging, as well as feedback-based pulse control embodiments that evaluate voltage changes due to concentration shifts are described.

Description

[Technical field]

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS This application claims priority to and the benefit of U.S. Provisional Patent Application No. 63 / 325,509, filed March 30, 2022, which is incorporated by reference herein in its entirety for all purposes.

[0002] The subject matter described herein relates generally to systems, devices, and methods for pulse charging and pulse heating of rechargeable energy sources. [Background technology]

[0003] Electrical energy storage systems are a key aspect in the global transition to cleaner forms of energy. Electrical energy storage systems are found in a host of stationary and mobile applications. Electrical energy storage systems in the form of packs can be used to power hybrid and fully electric vehicles and can be used to store electricity generated by the vehicle (e.g., through the use of regenerative braking). Electrical energy storage systems can be located in stacks or racks and can be used to store and supply energy for residential, commercial, and industrial facilities and can be integrated with or used to form grids and microgrids.

[0004] These energy storage systems (ESS) require periodic charging to replenish the discharged power. Several deficiencies and problems associated with existing charging methods have been identified, such as heat loss, degradation, and reduced charging rates. For example, the very long charging times of electric vehicles (EVs) are a major factor limiting their widespread acceptance. Using traditional constant current charging methods, it can take several hours to fully charge a battery pack. Such long waiting times create significant inconvenience and inefficiency when using an EV for trips outside the range of a single charge for the EV. Thus, traditional EVs are most typically used for local commuting, or trips that can be completed without the need for recharging the battery pack. Within range of charging stations that can charge at higher voltages in shorter times, repeated use of such stations can result in a dramatic reduction in the lifespan of the battery pack.

[0005] The adverse effects of slow charging times are not limited to EVs, as systems adapted for use in stationary applications can also benefit. Additionally, any device that relies on a battery pack to provide power, such as power tools, drones, and remotely operated vehicles, can potentially benefit.

[0006] The response of a battery, such as a lithium-ion battery, to charging depends on the temperature of the battery. If a lithium-ion battery is charged and the anode or cathode overvoltage is too high while still at a relatively low temperature, the battery can become severely degraded. This can lead to failure due to phenomena such as lithium coating in the power cells.

[0007] For these and other reasons, a need exists for improved systems, devices, and methods for fast charging and / or heating of energy sources. Summary of the Invention [Means for solving the problem]

[0008] Described herein are exemplary embodiments of systems, devices, and methods for fast charging an energy source, either alone or as part of an energy storage system (e.g., battery packs in electric vehicles, energy buffers in stationary systems, microgrids, etc.). The embodiments described herein can include heating the energy source through application of a preheat signal that increases the source temperature and reduces the overall impedance of the energy source so that accelerated electrochemical reactions are possible through subsequent charging. The embodiments can include charging the energy source with charge pulses at a frequency that passes through the double sheet capacitance of the energy source to reduce the activation impedance of the source and enable faster charging of the source without degradation reactions. The embodiments can also include a combination of a pulse preheat or pulse charging stage and a constant current (or non-pulsed) charging stage at a higher temperature, and the embodiments can include at least one instance of all three stages. The embodiments described herein are particularly suitable for application within a cascaded modular energy storage system, where each module includes at least one energy source and switch circuitry that can apply current in a pulsed manner for preheating and / or charging.

[0009] Embodiments are described for evaluating one or more parameters of an energy source to be charged and utilizing the evaluated parameters in selecting settings for execution of a heating and / or charging protocol. The parameters may be measured and retrieved by the system or based on prior measurements or representative values ​​stored in a memory (local or remote). Examples of parameters may include impedance, inductance, and thermal properties. Examples of settings may relate to frequency, voltage, current, or timing of the heating or charging signal.

[0010] An embodiment is described for evaluating a voltage change caused by a concentration shift in an energy source due to charging. The evaluated voltage change can be used as real-time feedback to adjust the charging process. For example, the evaluated voltage can be an activation overpotential due to a concentration shift and can be used as feedback to adjust the charging current (or voltage) limit to avoid exceeding the allowed anode overpotential (and any associated deleterious effects).

[0011] Other systems, devices, methods, features, and advantages of the subject matter described herein will be or become apparent to one with skill in the art upon review of the following drawing description and detailed description. All such additional systems, methods, features, and advantages are intended to be included within this specification, be within the scope of the subject matter described herein, and be protected by the accompanying claims. Features of the example embodiments should not be construed as limiting the scope of the appended claims unless there is an express recitation of those features in the claims. [Brief description of the drawings]

[0012] Details of the subject matter described herein, both as to its structure and operation, may be apparent from consideration of the accompanying drawings, in which like reference numerals refer to like parts. The components in the drawings are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the subject matter. Moreover, all illustrations are intended to convey the concept that relative sizes, shapes, and other detailed attributes may be illustrated generally, rather than literally or precisely.

[0013] [Figure 1A] FIG. 1 is a block diagram illustrating an exemplary embodiment of a modular energy system. [Figure 1B] Same as above. [Figure 1C] Same as above. [Figure 1D] FIG. 1 is a block diagram illustrating an exemplary embodiment of a control device for an energy system. [Figure 1E] Same as above. [Figure 1F] FIG. 1 is a block diagram illustrating an example embodiment of a modular energy system coupled to a load and a charging source. [Figure 1G] Same as above. [Figure 2A] FIG. 1 is a block diagram illustrating an example embodiment of a module and control system within an energy system. [Figure 2B] Same as above. [Figure 2C] FIG. 2 is a block diagram illustrating an example embodiment of a physical configuration of modules. [Figure 2D] FIG. 1 is a block diagram depicting an exemplary embodiment of the physical configuration of a modular energy system. [Figure 3A] 1 is a block diagram illustrating an example embodiment of a module having various electrical configurations. [Figure 3B] Same as above. [Figure 3C] Same as above. [Figure 4A] FIG. 2 is a schematic diagram illustrating an exemplary embodiment of an energy source. [Figure 4B] Same as above. [Figure 4C] Same as above. [Figure 4D] Same as above. [Figure 4E] Same as above. [Figure 4F] Same as above. [Figure 5A] FIG. 2 is a schematic diagram illustrating an exemplary embodiment of an energy buffer. [Figure 5B] Same as above. [Figure 5C] Same as above. [Figure 6A] FIG. 2 is a schematic diagram illustrating an exemplary embodiment of a converter. [Figure 6B] Same as above. [Figure 6C] Same as above. [Figure 7A] FIG. 1 is a block diagram illustrating an example embodiment of a modular energy system having various topologies. [Figure 7B] Same as above. [Figure 7C] Same as above. [Figure 7D] Same as above. [Figure 7E] Same as above. [Figure 8A] 1 is a plot depicting an example output voltage of a module. [Figure 8B] 1 is a plot depicting an example multi-level output voltage of a module array. [Figure 8C] 1 is a plot depicting exemplary reference and carrier signals that can be used in a pulse width modulation control technique. [Figure 8D] 1 is a plot depicting exemplary reference and carrier signals that can be used in a pulse width modulation control technique. [Figure 8E] 4 is a plot depicting exemplary switch signals generated in accordance with a pulse width modulation control technique. [Figure 8F] 1 is a plot depicting an exemplary multi-level output voltage produced by superposition of output voltages from an array of modules under a pulse width modulation control technique. [Figure 9A] FIG. 1 is a block diagram illustrating an exemplary embodiment of a controller for a modular energy system. [Figure 9B] Same as above. [Figure 10A] FIG. 1 is a block diagram depicting an example embodiment of a multi-phase modular energy system having interconnected modules. [Figure 10B] 10B is a schematic diagram illustrating an exemplary embodiment of an interconnection module in the multi-phase embodiment of FIG. 10A. [Figure 10C] FIG. 1 is a block diagram depicting an example embodiment of a modular energy system having two subsystems connected together by an interconnection module. [Figure 10D] FIG. 1 is a block diagram depicting an example embodiment of a three-phase modular energy system having interconnected modules supplying auxiliary loads. [Figure 10E]FIG. 10E is a schematic diagram illustrating an exemplary embodiment of an interconnection module in the multi-phase embodiment of FIG. 10D. [Figure 10F] FIG. 1 is a block diagram depicting another exemplary embodiment of a three-phase modular energy system having interconnected modules supplying auxiliary loads. [Figure 11A] 1 is a plot illustrating a framework for explaining several example embodiments of a fast charging protocol. [Figure 11B] Same as above. [Figure 11C] 11A-11C are graphs of current versus time depicting an exemplary embodiment of a preheat pulse train with and without a time gap, respectively; [Figure 11D] Same as above. [Figure 11E] 11 is a graph of current versus time depicting an exemplary embodiment of a preheat signal applied during multiple sub-stages. [Figure 11F] 1 is a current versus time graph illustrating an exemplary embodiment of a pulse charge signal for use in a pulse charge phase. [Figure 12A] FIG. 1 is a cross-sectional view of a generalized lithium-ion battery cell. [Figure 12B] FIG. 1 is an explanatory diagram depicting an illustration of an enlarged anode and cathode and listing examples of degradation modes that may occur within a typical lithium-ion battery cell. [Figure 12C] 1 is a graph depicting exemplary voltages on a lithium-ion cell over a range of states of charge. [Figure 12D] 1 is an electrical schematic model of a battery cell. [Figure 12E] 1 is a plot depicting an example impedance response of a lithium-ion cell. [Figure 12F] 1 is a plot depicting an example voltage response to a charge pulse applied to a lithium-ion cell. [Figure 12G] 1 is a plot depicting an exemplary concentration gradient within a lithium-ion cell. [Figure 13A]4 is a graph depicting exemplary levels of a constant current charging signal during a constant current charging phase. [Figure 13B] 11 is a graph depicting another exemplary embodiment of a fast charging protocol in which the magnitude of the constant current signal is gradually decreased. [Figure 14] 1 is a series of plots depicting an exemplary embodiment of monitoring indicating that lithium coating has occurred. [Figure 15A] 1A-1C are plots of absolute and normalized capacity retention comparing experimental data of constant current charging and an exemplary embodiment of pulse charging performed on a pair of lithium ion battery cells rated for use in power applications; [Figure 15B] Same as above. [Figure 16A] 1A-1C are plots of absolute and normalized capacity retention comparing experimental data of constant current charging and an exemplary embodiment of a fast charging protocol, respectively, performed on a pair of lithium ion battery cells rated for use in power applications. [Figure 16B] Same as above. [Figure 16C] FIG. 16C is a graph of capacity versus time and FIG. 16D is a graph of voltage versus time, both showing data collected from running one exemplary cycle of a fast charging protocol on a battery cell. [Figure 16D] Same as above. [Figure 17A] 1 is a plot of voltage versus capacity comparing experimental data of constant current charging and an exemplary embodiment of pulse charging, respectively, performed on a pair of lithium ion battery cells rated for use in power applications; [Figure 17B] Same as above. [Figure 18A] 13 is a plot of the imaginary and real impedance components of a constant current charged cell and a pulse charged cell at end of life. [Figure 18B] 1 is a plot of cell voltage versus time depicting experimental data collected for a lithium-ion cell subjected to constant current charging and pulse charging with different pulse durations. [Figure 19A] FIG. 1 is a block diagram illustrating an exemplary embodiment of a fast charging protocol implementation for various battery types. [Figure 19B] Same as above. [Figure 19C] Same as above. [Figure 19D] Same as above. [Figure 19E] Same as above. [Figure 19F] Same as above. [Figure 19G] Same as above. [Figure 20A] FIG. 1 is a block diagram illustrating an example embodiment of a system configuration that can be used with the heating and charging protocols described herein. [Figure 20B] Same as above. [Figure 20C] Same as above. [Figure 20D] Same as above. [Figure 20E] Same as above. [Figure 20F] Same as above. [Figure 21] FIG. 11 is a flow diagram depicting an exemplary method for evaluating parameters of an energy source and setting and executing a heating and / or charging protocol based on the evaluated parameters. [Figure 22] 1 is a voltage versus current plot illustrating example IV curves of a battery cell under balanced and unbalanced conditions. [Diagram 23] 1 is a plot of voltage versus state of charge for an example graphite anode. [Figure 24A] FIG. 11 is a flow diagram depicting an exemplary method for evaluating voltage changes due to concentration shifts and adjusting charging parameters accordingly. [Figure 24B] FIG. 13 is a flow diagram depicting another exemplary method for evaluating voltage changes due to concentration shifts and adjusting charging parameters accordingly, with preceding steps relating to characterization and validation. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Before describing the present subject matter in detail, it is to be understood that this disclosure is not limited to particular embodiments described, which may, of course, vary. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting, since the scope of the present disclosure will be limited only by the appended claims.

[0015] Before describing exemplary embodiments relating to heating and / or charging energy systems, it is useful to first describe in more detail classes of energy systems with which exemplary embodiments can be used. With reference to Figures 1A-10F, the following sections describe various applications in which embodiments of modular energy systems, embodiments of control systems or devices for modular energy systems, configurations of embodiments of modular energy systems with respect to charging sources and loads, embodiments of individual modules, embodiments of topologies for placement of modules in a system, embodiments of control methods, embodiments of balancing operational characteristics of modules in a system, and embodiments of use of interconnected modules can be implemented.

[0016] Application Examples A stationary application is one in which the modular energy system is located at a fixed location when in use, but may be capable of being transported to an alternative location when not in use. The module-based energy system resides in a static location while providing electrical energy for consumption by one or more other entities, or storing or buffering energy for later consumption. Examples of stationary applications in which the embodiments disclosed herein may be used include, but are not limited to, energy systems for use by or within one or more residential structures or locales, energy systems for use by or within one or more industrial structures or locales, energy systems for use by or within one or more commercial structures or locales, energy systems for use by or within one or more government structures or locales (including both military and non-military uses), energy systems for charging the mobile applications described below (e.g., charging sources or charging stations), and systems that convert solar power, wind power, geothermal energy, fossil fuels, or nuclear reactions into electricity for storage. Stationary applications often supply loads such as grids and microgrids, motors, and data centers. Stationary energy systems can be used in either a storage or non-storage role.

[0017] Mobile applications, sometimes referred to as traction applications, are generally those in which a module-based energy system is located on or within an entity to store and provide electrical energy for conversion to power by a motor to move or assist in moving the entity. Examples of mobile entities that may use the embodiments disclosed herein include, but are not limited to, electric and / or hybrid entities that move on or under land, on or under the sea, above and out of contact with land or sea (e.g., flying or hovering in the air), or through space. Examples of mobile entities that may use the embodiments disclosed herein include, but are not limited to, vehicles, trains, trams, ships, watercraft, aircraft, and spacecraft. Examples of mobile vehicles that may use the embodiments disclosed herein include, but are not limited to, those with only one wheel or truck, those with only two wheels or trucks, those with only three wheels or trucks, those with only four wheels or trucks, and those with five or more wheels or trucks. Examples of mobile entities that may use the embodiments disclosed herein include, but are not limited to, automobiles, buses, trucks, motorcycles, scooters, electric bicycles, industrial vehicles, mining vehicles, air vehicles (e.g., airplanes, helicopters, drones, etc.), maritime vessels (e.g., commercial ships, ships, yachts, boats, or other watercraft), submarines, locomotives or rail-based vehicles (e.g., trains, trams, etc.), military vehicles, spacecraft, and satellites.

[0018] Portable power applications include applications in which devices that are portable by humans and therefore relatively smaller than a stationary ESS or EV receive power from one or more energy sources. Portable devices are generally powered by one or more battery power cells, typically lithium ion, although they are not so limited. Examples of portable devices can include power tools and professional grade video cameras, portable power equipment, mobile phones, headsets, and wearable electronic devices.

[0019] In describing embodiments herein, reference may be made to a particular stationary application (e.g., grid, microgrid, data center, cloud computing environment), mobile application (e.g., electric vehicle), or portable power application. Such references are made for ease of description and are not meant to imply that a particular embodiment is limited to use only in that particular application. Embodiments of a system for powering a motor can be used in mobile applications, stationary applications, and portable power applications. While certain configurations may be more suitable for some applications than others, all exemplary embodiments disclosed herein can be used in both mobile and stationary applications unless otherwise specified.

[0020] Conventional systems that use one or more batteries may arrange those batteries in various configurations within an energy storage assembly. For example, the energy storage assembly may be relatively small, e.g., a battery with only a single cell, or a battery module with multiple cells connected together in a hardwired (e.g., non-switchable) series and / or parallel configuration, or may be larger and more complex, e.g., multiple battery modules (each with multiple cells) connected together in a hardwired (e.g., non-switchable) series and / or parallel configuration (such as a conventional EV battery pack). These assembly configurations are typically charged by applying a DC voltage across the assembly. In the pulse charging and pulse heating embodiments described herein, a voltage or current may be applied to these assembly configurations in a pulsed manner to achieve desired effects such as reduced charging time and temperature control. Pulsing may be performed, for example, through the addition of a new switch circuit between the charging source and the energy storage assembly, or through the use of an existing switch circuit (e.g., an inverter), either in the charging source or in a system or device having the assembly.

[0021] The embodiments described herein may also be used with energy storage systems having cascaded or distributed AC-DC converters, for example, where each battery module has a separate converter associated with it and the applied DC charging current or power may be pulsed individually to each battery module. Examples of these and other energy storage systems are described in the following sections with reference to system 100.

[0022] Example of a module-based energy system FIG. 1A is a block diagram depicting an exemplary embodiment of a module-based energy system 100. Here, the system 100 includes a control system 102 communicatively coupled to N converter source modules 108-1 through 108-N via communication paths or links 106-1 through 106-N, respectively. The modules 108 are configured to store energy and output energy to a load 101 (or other modules 108) as needed. In these embodiments, any number of modules 108 greater than or equal to two can be used (e.g., N is 2 or greater). The modules 108 can be connected to each other in various manners, as described in more detail with respect to FIGS. 7A-7E. For ease of illustration, in FIGS. 1A-1C, the modules 108 are shown connected in series or as a one-dimensional array, with the Nth module being coupled to the load 101.

[0023] The system 100 is configured to provide power to a load 101. The load 101 can be any type of load, such as a motor or a grid. The system 100 is also configured to store power received from a charging source. FIG. 1F is a block diagram illustrating an exemplary embodiment of the system 100 having a power input interface 151 for receiving power from a charging source 150 and a power output interface for outputting power to the load 101. In this embodiment, the system 100 can receive and store power via the interface 151 while simultaneously outputting power via the interface 152. FIG. 1G is a block diagram illustrating another exemplary embodiment of the system 100 having a switchable interface 154. In this embodiment, the system 100 can select, or can be instructed to select, between receiving power from the charging source 150 and outputting power to the load 101. The system 100 can be configured to supply multiple loads 101, including both primary and auxiliary loads, and / or receive power from multiple charging sources 150 (e.g., a utility-operated power grid and local renewable energy sources (e.g., solar)).

[0024] 1B depicts another exemplary embodiment of system 100, where control system 102 is implemented as a master control device (MCD) 112 communicatively coupled to N different local control devices (LCDs) 114-1 to 114-N via communication paths or links 115-1 to 115-N, respectively. Each LCD 114-1 to 114-N is communicatively coupled to one module 108-1 to 108-N via communication paths or links 116-1 to 116-N, respectively, such that there is a 1:1 relationship between LCD 114 and module 108.

[0025] 1C depicts another exemplary embodiment of system 100, in which MCD 112 is communicatively coupled to M different LCDs 114-1 through 114-M via communication paths or links 115-1 through 115-M, respectively. Each LCD 114 is coupled to and can control two or more modules 108. In the example shown, each LCD 114 is communicatively coupled to two modules 108, such that M LCDs 114-1 through 114-M are coupled to 2M modules 108-1 through 108-2M via communication paths or links 116-1 through 116-2M, respectively.

[0026] The control system 102 may be configured as a single device for the entire system 100 (e.g., FIG. 1A) or may be distributed across or implemented as multiple devices (e.g., FIGS. 1B-1C). In some embodiments, the control system 102 may be distributed among the LCDs 114 associated with the modules 108 such that the MCD 112 is not necessary and may be omitted from the system 100.

[0027] The control system 102 can be configured to perform the control using software (instructions stored in memory that are executable by a processing circuit), hardware, or a combination thereof. One or more devices of the control system 102 can each include a processing circuit 120 and a memory 122, as shown herein. Exemplary implementations of the processing circuit and memory are further described below.

[0028] The control system 102 may have a communication interface for communicating with devices 104 external to the system 100 via communication links or paths 105. For example, the control system 102 (e.g., the MCD 112) may output data or information related to the system 100 to another control device 104 (e.g., a vehicle's electronic control unit (ECU) or motor control unit (MCU) in a mobile application, a grid controller in a stationary application, etc.).

[0029] The communication paths or links 105, 106, 115, 116, and 118 (FIG. 2B) can each be a wired (e.g., electrical, optical) or wireless communication path that communicates data or information bidirectionally, in a parallel or serial manner. The data can be communicated in a standard (e.g., IEEE, ANSI) format or a custom (e.g., proprietary) format. In an automotive application, the communication path 115 can be configured to communicate according to a FlexRay or CAN protocol. The communication paths 106, 115, 116, and 118 can also provide wired power to directly provide operating power for the system 102 from one or more modules 108. For example, operating power for each LCD 114 can be provided only by the one or more modules 108 to which it is connected, and operating power for the MCD 112 can be provided indirectly (e.g., via the automotive power network) from one or more of the modules 108.

[0030] The control system 102 is configured to control one or more modules 108 based on status information received from the same or different one or more modules 108. The control may also be based on one or more other factors, such as the requirements of the load 101. Controllable aspects include, but are not limited to, one or more of the voltage, current, phase, and / or output power of each module 108.

[0031] Status information for each module 108 in the system 100 can be communicated to the control system 102, which can control each module 108-1...108-N independently. Other variations are possible. For example, a particular module 108 (or a subset of modules 108) can be controlled based on status information for that particular module 108 (or subset), based on status information for a different module 108 that is not the particular module 108 (or subset), based on status information for all modules 108 other than the particular module 108 (or subset), based on status information for the particular module 108 (or subset) and status information for at least one other module 108 that is not the particular module 108 (or subset), or based on status information for all modules 108 in the system 100.

[0032] The status information may be information regarding one or more aspects, characteristics, or parameters of each module 108. Types of status information may include, but are not limited to, the following aspects of a module 108 or one or more of its components (e.g., energy sources, energy buffers, converters, monitoring circuits): state of charge (SOC) of one or more energy sources of the module (e.g., the charge level of an energy source relative to its capacity, such as a fraction or percentage), state of health (SOH) of one or more energy sources of the module (e.g., a figure of merit of an energy source compared to its ideal state), temperature of one or more energy sources or other components of the module, capacity of one or more energy sources of the module, voltage of one or more energy sources and / or other components of the module, current of one or more energy sources and / or other components of the module, state of power (SOP) (e.g., available power limit of an energy source during discharging and / or charging), state of energy (SOE) (e.g., the current level of available energy of an energy source relative to the maximum available energy of the energy source), and / or the presence or absence of a fault in any one or more of the components of the module.

[0033] The LCD 114 can be configured to receive status information from each module 108 or determine status information from monitoring signals or data received from or within each module 108 and communicate that information to the MCD 112. In some embodiments, each LCD 114 can communicate raw collected data to the MCD 112, which then algorithmically determines status information based on the raw data. The MCD 112 can then use the module 108 status information to make control decisions accordingly. The decisions can take the form of instructions, commands, or other information (such as a modulation index as described herein) that can be utilized by the LCD 114 to maintain or adjust the operation of each module 108.

[0034] For example, the MCD 112 may receive status information and evaluate the information to determine differences between at least one module 108 (e.g., its components) and at least one or more other modules 108 (e.g., its comparable components). For example, the MCD 112 may determine that a particular module 108 is operating in one of the following states compared to one or more other modules 108: relatively low or high SOC, relatively low or high SOH, relatively low or high capacity, relatively low or high voltage, relatively low or high current, relatively low or high temperature, or with or without a fault. In such an example, the MCD 112 may output control information to decrease or increase (depending on the state) a relevant aspect (e.g., output voltage, current, power, temperature) of that particular module 108. In this manner, the utilization of an outlier module 108 (e.g., operating at a relatively low SOC or higher temperature) may be decreased to cause a relevant parameter (e.g., SOC or temperature) of that module 108 to converge toward the parameter of one or more other modules 108.

[0035] The decision to adjust the operation of a particular module 108 can be made by comparing the status information to a predefined threshold, limit, or condition, without necessarily comparing it to the status of other modules 108. The predefined threshold, limit, or condition can be a static threshold, limit, or condition, such as set by a manufacturer that does not change during use. The predefined threshold, limit, or condition can be a dynamic threshold, limit, or condition that may or may not change during use. For example, the MCD 112 can adjust the operation of a module 108 if the status information for that module 108 indicates that the module 108 is operating in violation of (e.g., above or below) a predefined threshold or limit, or outside a predefined range of acceptable operating conditions. Similarly, the MCD 112 can adjust the operation of a module 108 if the status information for that module 108 indicates the presence of an actual or potential fault (e.g., an alarm or warning), or indicates the absence or removal of an actual or potential fault. Examples of faults include, but are not limited to, actual failure of a component, potential failure of a component, short circuit or other excessive current condition, open circuit, excessive voltage condition, failure to receive communications, reception of corrupted data, etc. Depending on the type and severity of the fault, utilization of the faulty module may be reduced to avoid damaging the module, or utilization of the module may be halted entirely. For example, if a given module fails, MCD 112 or LCD 114 may cause that module to enter a bypass state as described herein.

[0036] The MCD 112 may control the modules 108 in the system 100 to achieve or converge toward a desired goal. The goal may be, for example, operation of all modules 108 at the same or similar levels relative to one another or within predetermined thresholds, limits, or conditions. This process is also referred to as balancing or seeking to achieve balance in the operation or operating characteristics of the modules 108. As used herein, the term "balance" is used broadly to convey that absolute equivalence between the modules 108 or their components is not required, but rather, the operation of the system 100 may be used to actively reduce differences in operation (or operating conditions) between the modules 108 that would otherwise exist.

[0037] The MCD 112 may communicate control information to the LCD 114 for purposes of controlling the module 108 associated with the LCD 114. The control information may be, for example, a modulation index and reference signal, a modulation reference signal, or otherwise, as described herein. Each LCD 114 may use (e.g., receive and process) the control information to generate switch signals that control the operation of one or more components (e.g., converters) in the associated module 108. In some embodiments, the MCD 112 generates the switch signals directly and outputs them to the LCD 114, which relays the switch signals to the intended module components.

[0038] All or a portion of the control system 102 may be combined with a system external control device 104 that controls one or more other aspects of the mobile or stationary application. When integrated into this shared or common control device (or subsystem), control of the system 100 may be implemented in any desired manner, such as one or more software applications executed by the processing circuitry of the shared device, the hardware of the shared device, or a combination thereof. Non-exhaustive examples of external control devices 104 include a vehicle ECU or MCU having control capability for one or more other vehicle functions (e.g., motor control, driver interface control, traction control, etc.), a grid or microgrid controller responsible for one or more other power management functions (e.g., load interface, load power requirement prediction, transmission and switching, interfacing with charging sources (e.g., diesel, solar, wind), charging source power prediction, backup source monitoring, asset dispatch, etc.), and a data center control subsystem (e.g., environmental control, network control, backup control, etc.).

[0039] 1D and 1E are block diagrams depicting an example embodiment of a shared or common control device (or system) 132 in which the control system 102 may be implemented. In FIG. 1D, the common control device 132 includes a master control device 112 and an external control device 104. The master control device 112 includes an interface 141 for communication with an LCD 114 via path 115, as well as an interface 142 for communication with the external control device 104 via an internal communication bus 136. The external control device 104 includes an interface 143 for communication with the master control device 112 via the bus 136, and an interface 144 for communication with other entities throughout the application (e.g., vehicle or grid components) via communication path 136. In some embodiments, the common control device 132 may be integrated as a common housing or package, with the devices 112 and 104 implemented as separate integrated circuit (IC) chips or packages contained therein.

[0040] In FIG. 1E, the external control device 104 functions as a common control device 132, with the master control function being implemented as a component within the device 104. This component 112 can be or include software or other program instructions stored and / or hard-coded within the memory of the device 104 and executed by its processing circuitry. The component can also include dedicated hardware. The component can be a self-contained module or core with one or more internal hardware and / or software interfaces (e.g., application program interfaces (APIs)) for communication with the operating software of the external control device 104. The external control device 104 can manage communication with the LCD 114 via interface 141 and other devices via interface 144. In various embodiments, the devices 104 / 132 can be integrated as a single IC chip, multiple IC chips in a single package, or multiple semiconductor packages in a common housing.

[0041] 1D and 1E, the master control functionality of the system 102 is shared in the common device 132, although other divisions of the shared control are permitted. For example, some of the master control functionality may be distributed between the common device 132 and the dedicated MCD 112. In another example, both the master control functionality and at least some of the local control functionality may be implemented in the common device 132 (e.g., with the remaining local control functionality implemented in the LCD 114). In some embodiments, all of the control system 102 is implemented in the common device (or subsystem) 132. In some embodiments, the local control functionality is implemented in a device shared with another component of each module 108, such as a battery management system (BMS).

[0042] Example of a module in a cascaded energy system The module 108 may include one or more energy sources, a power electronics converter, and optionally, an energy buffer. FIGS. 2A-2B are block diagrams depicting additional exemplary embodiments of the system 100 having a module 108 with a power converter 202, an energy buffer 204, and an energy source 206. The converter 202 may be a voltage converter or a current converter. Although the embodiments are described herein with reference to a voltage converter, the embodiments are not limited as such. The converter 202 may be configured to convert a direct current (DC) signal from the energy source 206 to an alternating current (AC) signal and output it via a power connection 110 (e.g., an inverter). The converter 202 may also receive an AC or DC signal via the connection 110 and apply it to the energy source 206 in either polarity, continuous or pulsed form. The converter 202 may be or include an arrangement of switches (e.g., power transistors), such as a half-bridge of a full bridge (H-bridge). In some embodiments, the converter 202 includes only switches, and the converter (and the module as a whole) does not include a transformer.

[0043] Converter 202 may also (or alternatively) be configured to perform AC to DC conversion (e.g., a rectifier), DC to DC conversion, and / or AC to AC conversion (e.g., in combination with an AC-DC converter), such as for charging a DC energy source from an AC source. In some embodiments, such as for performing AC-AC conversion, converter 202 may include a transformer, either alone or in combination with one or more power semiconductors (e.g., switches, diodes, thyristors, etc.). In other embodiments, such as where weight and cost are important factors, converter 202 may be configured to perform the conversion without a transformer, with only power switches, power diodes, or other semiconductor devices.

[0044] The energy source 206 is preferably a robust energy storage device capable of outputting direct current and having an energy density suitable for energy storage applications for powering devices. The energy source 206 can be an electrochemical battery, such as a single battery cell or multiple battery cells connected together in a battery module or array, or any combination thereof. Figures 4A-4D are schematic diagrams depicting exemplary embodiments of the energy source 206 configured as a single battery cell 402 (Figure 4A), a battery module having a series connection of multiple (e.g., four) cells 402 (Figure 4B), a battery module having a parallel connection of a single cell 402 (Figure 4C), and a battery module having a parallel connection with legs each having two cells 402 (Figure 4D). A non-exhaustive list of examples of battery types is provided elsewhere herein.

[0045] The energy source 206 can also be a high energy density (HED) capacitor, such as an ultracapacitor or a supercapacitor. HED capacitors can be configured as double layer capacitors (electrostatic charge storage), pseudocapacitors (electrochemical charge storage), hybrid capacitors (electrostatic and electrochemical), or otherwise, as opposed to the solid dielectric types of typical electrolytic capacitors. In addition to higher capacitance, HED capacitors can have an energy density that is 10-100 times (or more) that of electrolytic capacitors. For example, HED capacitors can have a specific energy of greater than 1.0 watt-hours per kilogram (Wh / kg) and a capacitance of greater than 10-100 Farads (F). Similar to the batteries described with respect to FIGS. 4A-4D, the energy source 206 can be configured as a single HED capacitor or multiple HED capacitors connected together in an array (e.g., in series, parallel, or a combination thereof).

[0046] The energy source 206 may also be a fuel cell. The fuel cell may be rechargeable and may be a single fuel cell, multiple fuel cells connected in series or parallel, or a fuel cell module. The fuel cell may be configured to be rechargeable, and examples of fuel cell types include proton exchange membrane fuel cells (PEMFCs), phosphoric acid fuel cells (PAFCs), solid acid fuel cells, alkaline fuel cells, high temperature fuel cells, solid oxide fuel cells, molten electrolyte fuel cells, and the like. Similar to the batteries described with respect to FIGS. 4A-4D, the energy source 206 may be configured as a single fuel cell or multiple fuel cells connected together in an array (e.g., in series, parallel, or a combination thereof). The foregoing examples of source classes (e.g., batteries, capacitors, and fuel cells) and types (e.g., chemical and / or structural configurations within each class) are not intended to form an exhaustive list, and one of ordinary skill in the art will recognize other variations that fall within the scope of the present subject matter.

[0047] The energy buffer 204 compensates for fluctuations in current across the DC line or DC link (e.g., +V DCL and -V DCL ) may be attenuated or filtered. These fluctuations may be relatively low (e.g., kilohertz) or high (e.g., megahertz) frequency fluctuations or harmonics caused by switching of converter 202, or other transients. These fluctuations may be absorbed by buffer 204 instead of being passed to source 206 or ports IO3 and IO4 of converter 202.

[0048] The power connection 110 is a connection for transferring energy or power to, from, and through the module 108. The module 108 can output energy from the energy source 206 to the power connection 110 where the energy can be transferred to other modules or loads in the system. The module 108 can also receive energy from other modules 108 or charging sources (DC chargers, single-phase chargers, multi-phase chargers). Signals can also pass through the module 108 bypassing the energy source 206. The routing of energy or power to and from the module 108 is performed by the converter 202 under the control of the LCD 114 (or another entity of the system 102).

[0049] In the embodiment of Figure 2A, the LCD 114 may be implemented as a separate component from the module 108 (e.g., not in a shared module housing) and may be connected to and communicate with the converter 202 via communication path 116. In the embodiment of Figure 2B, the LCD 114 may be included as a component of the module 108 and may be connected to and communicate with the converter 202 via an internal communication path 118 (e.g., a shared bus or a separate connection). The LCD 114 may also be capable of receiving and transmitting signals from the energy buffer 204 and / or the energy source 206 via paths 116 or 118.

[0050] The module 108 may also include monitoring circuitry 208 configured to monitor (e.g., collect, sense, measure, and / or determine) one or more aspects of the module 108 and / or its components, such as voltage, current, temperature, or other operating parameters that constitute status information (or that may be used, for example, to determine the status information by the LCD 114). The primary function of the status information is to describe the state of one or more energy sources 206 of the module 108 to enable a decision on how much to utilize the energy source relative to other sources in the system 100, although status information describing the state of other components (e.g., voltage, temperature, and / or presence of a fault in the buffer 204, temperature and / or presence of a fault in the converter 202, presence of a fault elsewhere in the module 108, etc.) may also be used in the utilization decision. The monitoring circuitry 208 may include one or more sensors, shunts, dividers, fault detectors, coulomb counters, controllers, or other hardware and / or software configured to monitor such aspects. The monitoring circuitry 208 may be separate from the various components 202, 204, and 206, or may be integrated with each component 202, 204, and 206 (as shown in FIGS. 2A-2B), or any combination thereof. In some embodiments, the monitoring circuitry 208 may be part of a battery management system (BMS) of the battery energy source 206, or may be shared with a battery management system (BMS) of the battery energy source 204. Discrete circuitry is not required to monitor each type of status information, as more than one type of status information may be monitored with a single circuit or device, or may otherwise be determined algorithmically without the need for additional circuitry.

[0051] The LCD 114 can receive status information (or raw data) regarding the module components via communication paths 116, 118. The LCD 114 can also transmit information to the module components via paths 116, 118. The paths 116 and 118 can include diagnostic, measurement, protection, and control signal lines. The transmitted information can be control signals for one or more module components. The control signals can be switch signals to the converter 202 and / or one or more signals requesting status information from the module components. For example, the LCD 114 can cause the status information to be transmitted via paths 116, 118 by directly requesting the status information or by applying a stimulus (e.g., a voltage) to generate the status information, possibly in combination with a switch signal that places the converter 202 in a particular state.

[0052] The physical configuration or layout of the module 108 can take a variety of forms. In some embodiments, the module 108 can include a common housing in which all module components, such as the converter 202, the buffer 204, and the source 206, are housed along with other optional components, such as an integrated LCD 114. In other embodiments, the various components can be separated into separate housings that are fastened together. FIG. 2C is a block diagram depicting an exemplary embodiment of the module 108, having a first housing 220 that holds the module's energy source 206 and associated electronics, such as monitoring circuitry, a second housing 222 that holds the module electronics, such as the converter 202, the energy buffer 204, and other associated electronics, such as monitoring circuitry, and a third housing 224 that holds the LCD 114 (not shown) for the module 108. In alternative embodiments, the module electronics and the LCD 114 can be housed in the same single housing. In yet other embodiments, the module electronics, the LCD 114, and the energy source can be housed in the same single housing for the module 108. Electrical connections between the various module components may proceed through the housings 220 , 222 , 224 and may be exposed to the exterior of either of the housings for connection with other devices, such as other modules 108 or MCD 112 .

[0053] The modules 108 of the system 100 can be physically arranged relative to each other in various configurations depending on the application needs and the number of loads. For example, in a stationary application where the system 100 supplies power to a microgrid, the modules 108 can be placed in one or more racks or other frameworks. Such a configuration may also be suitable for larger mobile applications such as offshore vessels. Alternatively, the modules 108 can be fixed together and located in a common housing called a pack. The rack or pack can have its own dedicated cooling system shared across all modules. The pack configuration is useful for small mobile applications such as electric vehicles. The system 100 can be implemented in one or more racks (e.g., for parallel supply to a microgrid), or one or more packs (e.g., servicing different motors of a vehicle), or a combination thereof. FIG. 2D is a block diagram depicting an exemplary embodiment of the system 100 configured as a pack with nine modules 108 electrically and physically coupled together in a common housing 230.

[0054] Examples of these and further configurations are described in International Application No. PCT / US20 / 25366, filed March 27, 2020, and entitled Module-Based Energy Systems Capable of Cascaded and Interconnected Configurations, and Methods Related Thereto, which is incorporated by reference in its entirety for all purposes.

[0055] 3A-3C are block diagrams depicting example embodiments of modules 108 having various electrical configurations. These embodiments are described as having one LCD 114 per module 108, with the LCD 114 housed within an associated module, but may be otherwise configured as described herein. FIG. 3A depicts a first example configuration of modules 108A within system 100. Module 108A includes an energy source 206, an energy buffer 204, and a converter 202A. Each component has a power connection port (e.g., terminal, connector), referred to herein as an IO port, through which power can be input and / or through which power can be output. Such ports may be referred to as input ports or output ports, depending on the context.

[0056] The energy source 206 can be configured as any of the energy source types described herein (e.g., a battery, HED capacitor, fuel cell, or others, as described with respect to FIGS. 4A-4D). Ports IO1 and IO2 of the energy source 206 can be connected to ports IO1 and IO2, respectively, of the energy buffer 204. The energy buffer 204 can be configured to buffer or filter high and low frequency energy pulsations that reach the buffer 204 through the converter 202 and that may otherwise degrade the performance of the module 108. The topology and components for the buffer 204 are selected to accommodate the maximum allowable amplitude of these high frequency voltage pulsations. Several (non-exhaustive) exemplary embodiments of the energy buffer 204 are depicted in the schematic diagrams of FIGS. 5A-5C. In FIG. 5A, the buffer 204 is configured with electrolytic and / or film capacitors C EB 5B, the buffer 204 is connected to two inductors L EB1 and L EB2 and two electrolytic and / or film capacitors C EB1 and C EB25C, the buffer 204 is formed by two inductors L EB1 and L EB2 and two electrolytic and / or film capacitors C EB1 and C EB2 and diode D EB and a quasi-Z source network 720 formed by

[0057] The ports IO3 and IO4 of the energy buffer 204 can be connected to the ports IO1 and IO2 of the converter 202A, which can be configured as any of the power converter types described herein. FIG. 6A is a schematic diagram illustrating an example embodiment of the converter 202A configured as a DC-AC converter that can receive DC voltages at ports IO1 and IO2 and switch to generate pulses at ports IO3 and IO4. The converter 202A can include multiple switches, where the converter 202A includes four switches S3, S4, S5, S6 arranged in a full-bridge configuration. The control system 102 or the LCD 114 can independently control each switch via the control input line 118-3 to each gate.

[0058] The switches can be any suitable switch type, such as power semiconductors, such as metal oxide semiconductor field effect transistors (MOSFETs) as shown here, insulated gate bipolar transistors (IGBTs), or gallium nitride (GaN) transistors. The semiconductor switches can operate at relatively high switching frequencies, thereby allowing the converter 202 to operate in a pulse width modulation (PWM) mode and respond to control commands within a relatively short time interval, if desired. This can provide high tolerance for output voltage regulation and fast dynamic behavior in transient modes.

[0059] In this embodiment, the DC line voltage V DCLcan be applied to the converter 202 between ports IO1 and IO2. Different combinations of switches S3, S4, S5, and S6 allow DCL By connecting the +V DCL , 0, and -V DCL The switch signal provided to each switch controls whether the switch is on (closed) or off (open). DCL To obtain -V, switches S3 and S6 are turned on while S4 and S5 are turned off. DCL can be obtained by turning on switches S4 and S5 and turning off S3 and S6. The output voltage can be set to zero (including near zero) or a reference voltage by turning on S3 and S5 with S4 and S6 turned off, or by turning on S4 and S6 with S3 and S5 turned off. These voltages can be output from the module 108 via the power connection 110. Ports IO3 and IO4 of the converter 202 can be connected (or formed) to module IO ports 1 and 2 of the power connection 110 to generate output voltages for use with output voltages from other modules 108.

[0060] The control or switch signals for the embodiments of converter 202 described herein can be generated in different manners depending on the control technique utilized by system 100 to generate the output voltage of converter 202. In some embodiments, the control technique is a PWM technique, such as Space Vector Pulse Width Modulation (SVPWM) or Sine Wave Pulse Width Modulation (SPWM), or variations thereof. FIG. 8A is a voltage versus time graph depicting an example of an output voltage waveform 802 of converter 202. For ease of explanation, the embodiments herein are described in the context of PWM control techniques, but the embodiments are not limited to such. Other classes of techniques can also be used. One alternative class is based on hysteresis, examples of which are described in WO 2018 / 231810 A1, WO 2018 / 232403 A1, and WO 2019 / 183553 A1, which are incorporated by reference herein for all purposes.

[0061] Each module 108 can be configured with multiple energy sources 206 (e.g., two, three, four or more). Each energy source 206 of a module 108 can be controllable (switchable) to supply power to the connection 110 (or receive power from a charging source) independently of the other sources 206 of the module. For example, all sources 206 can output power (or be charged) to the connection 110 at the same time, or only one (or a subset) of the sources 206 can supply power (or be charged) at any time. In some embodiments, the sources 206 of a module can exchange energy between themselves, e.g., one source 206 can charge another source 206. Each of the sources 206 can be configured as any energy source described herein (e.g., a battery, a HED capacitor, a fuel cell). Each of the sources 206 may be of the same class (e.g., each may be a battery, each may be a HED capacitor, or each may be a fuel cell) or may be of different classes (e.g., a first source may be a battery and a second source may be a HED capacitor or a fuel cell, or a first source may be a HED capacitor and a second source may be a fuel cell).

[0062] 3B is a block diagram illustrating an example embodiment of a module 108B in a dual energy source configuration having a primary energy source 206A and a secondary energy source 206B. Ports IO1 and IO2 of the primary source 202A can be connected to ports IO1 and IO2 of the energy buffer 204. Module 108B includes a converter 202B with an additional IO port. Ports IO3 and IO4 of the buffer 204 can be connected to ports IO1 and IO2 of the converter 202B, respectively. Ports IO1 and IO2 of the secondary source 206B can be connected to ports IO5 and IO2 of the converter 202B, respectively (and can also be connected to port IO4 of the buffer 204).

[0063] In this exemplary embodiment of module 108B, the primary energy source 202A, along with the other modules 108 of the system 100, supplies the average power required by the load. The secondary source 202B may function to assist the energy source 202 by providing additional power at load power peaks, or by absorbing excess power, or in other ways.

[0064] As mentioned above, both the primary source 206A and the secondary source 206B can be utilized at the same time or at different times depending on the switch state of the converter 202B. At the same time, the electrolytic capacitor and / or the film capacitor (C ES ) can be placed in parallel with source 206B as depicted in FIG. 4E to act as an energy buffer for source 206B, or energy source 206B can be configured to utilize a HED capacitor in parallel with another energy source (e.g., a battery or fuel cell) as depicted in FIG. 4F.

[0065] 6B and 6C are schematic diagrams depicting example embodiments of converters 202B and 202C, respectively. Converter 202B includes switch circuit portions 601 and 602A. Portion 601 includes switches S3-S6 configured as a full bridge in a manner similar to converter 202A and configured to selectively couple IO1 and IO2 to either IO3 and IO4, thereby varying the output voltage of module 108B. Portion 602A includes switches S1 and S2 configured as a half bridge and coupled between ports IO1 and IO2. A coupled inductor L C is connected between port IO5 and node 1, which exists between switch S1 and switch S2, so that switch portion 602A is a bidirectional converter that can regulate (boost or buck) voltage (or reverse current). Switch portion 602A ... DCL2Two different voltages, 0 and 1, can be generated at node 1. The current drawn from or input to the energy source 202B can be controlled by the coupled inductor L, for example, using a pulse width modulation technique or a hysteretic control method to commutate the switches S1 and S2. C This can be controlled by adjusting the voltage on the MOSFET. Other techniques can also be used.

[0066] Converter 202C differs from that of 202B because switch portion 602B includes switches S1 and S2 configured as a half-bridge and coupled between ports IO5 and IO2. C is connected between port IO1 and a node 1 that exists between switch S1 and switch S2 such that switch portion 602B is configured to regulate the voltage.

[0067] The control system 102 or the LCD 114 can independently control each switch of the converters 202B and 202C via the control input lines 118-3 to each gate. In these embodiments and the embodiment of FIG. 6A, the LCD 114 (not the MCD 112) generates the switching signals for the converter switches. Alternatively, the MCD 112 can generate switching signals that can be communicated directly to the switches or relayed by the LCD 114. In some embodiments, driver circuitry for generating the switching signals can be present in or associated with the MCD 112 and / or the LCD 114.

[0068] The aforementioned zero voltage configuration of converter 202 (S3 and S5 on with S4 and S6 off, or S4 and S6 on with S3 and S5 off) can also be referred to as a bypass state for a given module. This bypass state can be entered when a fault is detected in a given module, or when a system fault is detected that warrants shutting off two or more (or all) modules in an array or system. The module fault can be detected by LCD 114, and the control switching signal for converter 202 can be set to engage the bypass state without intervention by MCD 112. Alternatively, the fault information for a given module can be communicated by LCD 114 to MCD 112, which can then decide whether to engage the bypass state, and if so, can communicate a command to engage the bypass state to the LCD 114 associated with the faulty module, at which point LCD 114 can output a switching signal to cause engagement of the bypass state.

[0069] In embodiments in which the module 108 includes more than two energy sources 206, the converters 202B and 202C can be scaled accordingly such that each additional energy source 206B is coupled to an additional IO port that leads to an additional switch circuit portion 602A or 602B, depending on the needs of the particular source. For example, the dual source converter 202 can include both switch portions 202A and 202B.

[0070] A module 108 having multiple energy sources 206 can perform additional functions such as energy sharing between the energy sources 206, energy harvesting from within the application (e.g., regenerative braking), charging a primary source with a secondary source even while the entire system is in a discharging state, and active filtering of the module output. The active filtering function can also be performed by a module having a typical electrolytic capacitor in place of a secondary energy source. Examples of these functions are described in more detail in International Application No. PCT / US20 / 25366, filed March 27, 2020, and entitled Module-Based Energy Systems Capable of Cascaded and Interconnected Configurations, and Methods Related Thereto, and International Publication No. WO 2019 / 183553, filed March 22, 2019, and entitled Systems and Methods for Power Management and Control, both of which are incorporated herein by reference in their entirety for all purposes.

[0071] Each module 108 can be configured to supply its one or more energy sources 206 to one or more auxiliary loads. An auxiliary load is a load that requires a lower voltage than the primary load 101. An example of an auxiliary load can be, for example, an on-board electrical network of an electric vehicle, or an HVAC system of an electric vehicle. A load of the system 100 can be, for example, an electric vehicle motor or one of the phases of an electric grid. This embodiment can allow for a complete decoupling between the electrical characteristics of the energy source (terminal voltage and current) and the electrical characteristics of the load.

[0072] FIG. 3C is a block diagram depicting an exemplary embodiment of a module 108C configured to supply power to a first auxiliary load 301 and a second auxiliary load 302, the module 108C including an energy source 206, an energy buffer 204, and a converter 202B coupled together in a manner similar to FIG. 3B. The first auxiliary load 301 requires a voltage equal to the voltage provided by the source 206. The load 301 is coupled to IO ports 3 and 4 of the module 108C, which are in turn coupled to ports IO1 and IO2 of the source 206. The source 206 can output power to both the power connection 110 and the load 301. The second auxiliary load 302 requires a constant voltage lower than the voltage of the source 206. The load 302 is coupled to IO ports 5 and 6 of the module 108C, which are coupled to ports IO5 and IO2 of the converter 202B, respectively. The converter 202B is coupled to a coupled inductor L coupled to port IO5. C (FIG. 6B). The energy provided by the source 206 can be delivered to the load 302 through the switch portion 602 of the converter 202B. It is assumed that the load 302 has an input capacitor (if not, a capacitor can be added to the module 108C), so that the switches S1 and S2 are commutated to couple the coupled inductor L C 206 to a lower magnitude voltage required by the load 302.

[0073] Thus, module 108C can be configured to supply one or more first auxiliary loads in the manner described for load 301, with one or more first loads coupled to IO ports 3 and 4. Module 108C can also be configured to supply one or more second auxiliary loads in the manner described for load 302. If there are multiple second auxiliary loads 302, then for each additional load 302, module 108C can be scaled with additional dedicated module output ports (such as 5 and 6), additional dedicated switch portions 602, and additional converter IO ports coupled to the additional portions 602.

[0074] Thus, energy source 206 can supply power to any number of auxiliary loads (e.g., 301 and 302), as well as a corresponding portion of the system output power required by primary load 101. Power flow from source 206 to the various loads can be adjusted as desired.

[0075] The module 108 can be configured with two or more energy sources 206 (FIG. 3B) as needed to supply a first and / or second auxiliary load (FIG. 3C) by adding a switch portion 602 and converter port IO5 for each additional energy source 206B or second auxiliary load 302. Additional module IO ports (e.g., 3, 4, 5, 6) can be added as needed. The module 108 can also be configured as an interconnect module to exchange energy between two or more arrays, two or more packs, or two or more systems 100 (e.g., for balancing), as described further herein. This interconnect function can be combined with multiple source and / or multiple auxiliary load supply functions as well.

[0076] The control system 102 may perform a variety of functions with respect to the components of the modules 108A, 108B, and 108C. These functions may include managing the utilization of each energy source 206, protecting the energy buffer 204 from overcurrent, overvoltage, and high temperature conditions, and controlling and protecting the converter 202.

[0077] For example, the LCD 114 may receive one or more monitored voltages, temperatures, and currents from each energy source 206 (or monitoring circuitry) to manage (e.g., adjust by increasing, decreasing, or maintaining) the utilization of each energy source 206. The monitored voltages may be at least one, and preferably all, of the voltages of each basic component independent of other components of the source 206 (e.g., each individual battery cell, HED capacitor, and / or fuel cell), or the voltages of the group of basic components as a whole (e.g., the voltages of the battery array, HED capacitor array, and / or fuel cell array). Similarly, the monitored temperatures and currents may be at least one, and preferably all, of the temperatures and currents of each basic component independent of other components of the source 206, or the temperatures and currents of the group of basic components as a whole, or any combination thereof. The monitored signals may be status information that enables the LCD 114 to perform one or more of the following: calculate or determine an actual capacity, an actual state of charge (SOC) and / or state of health (SOH) of a base component or group of base components, set or output a warning or alarm indication based on the monitored and / or calculated status information, and / or send status information to the MCD 112. The LCD 114 may receive control information (e.g., modulation index, synchronization signals) from the MCD 112 and use this control information to generate switch signals for the converter 202 that manage the utilization of the source 206.

[0078] To protect the energy buffer 204, the LCD 114 can receive one or more monitored voltages, temperatures, and currents from the energy buffer 204 (or a monitoring circuit). The monitored voltages are measured by each basic component (e.g., C EB , C EB1 , C EB2 , L EB1 , L EB2 , D EB ) or the voltage of the group of basic components or buffer 204 as a whole (e.g., between IO1 and IO2, or between IO3 and IO4). Similarly, the monitored temperature and current can be at least one, preferably all, of the temperature and current of each basic component of buffer 204 independent of other components, or the temperature and current of the group of basic components or buffer 204 as a whole, or any combination thereof. The monitored signal can be status information that enables LCD 114 to perform one or more of the following: set or output a warning or alarm indication, communicate status information to MCD 112, or control converter 202 to adjust (increase or decrease) the utilization of source 206 and module 108 as a whole for buffer protection.

[0079] To control and protect the converter 202, the LCD 114 can receive control information (e.g., a modulated reference signal, or a reference signal and a modulation index) from the MCD 112, which can be used in conjunction with PWM techniques in the LCD 114 to generate control signals for each switch (e.g., S1-S6). The LCD 114 can receive current feedback signals from current sensors in the converter 202, which can be used for overcurrent protection along with one or more fault status signals from the converter switch driver circuits (not shown), which can carry information regarding the fault status (e.g., short circuit or open circuit fault modes) of all switches in the converter 202. Based on this data, the LCD 114 can determine which combination of switching signals to apply to manage the utilization of the module 108, and potentially to bypass or disconnect the converter 202 (and the entire module 108) from the system 100.

[0080] When controlling module 108C supplying a second auxiliary load 302, LCD 114 displays one or more monitored voltages (e.g., the voltage between IO port 5 and IO port 6) and one or more monitored currents (e.g., the current of load 302, the coupled inductor L C Based on these signals, the LCD 114 can adjust the switching cycles of S1 and S2 (e.g., by adjusting the modulation index or reference waveform) to control (and stabilize) the voltage on the load 302.

[0081] Example of a cascaded energy system topology Two or more modules 108 can be coupled together in a cascaded array that outputs a voltage signal formed by the superposition of the separate voltages generated by each module 108 in the array. FIG. 7A is a block diagram depicting an example embodiment of a topology for the system 100 in which N modules 108-1, 108-2...108-N are coupled together in series to form a series array 700. In this embodiment and all embodiments described herein, N can be any integer greater than 1. The array 700 includes a first system IO port SIO1 and a second system IO port SIO2 at which the array output voltage is generated. The array 700 can be used as a DC or single-phase AC energy source for DC or AC single-phase loads that can be connected to SIO1 and SIO2 of the array 700. FIG. 8A is a voltage versus time plot depicting an example of an output signal produced by a single module 108 with a 48 volt energy source. FIG. 8B is a voltage versus time plot depicting an exemplary single-phase AC output signal produced by an array 700 having six 48V modules 108 coupled in series.

[0082] The system 100 can be arranged in a wide variety of different topologies to meet various application needs. The system 100 can supply polyphase power (e.g., 2-phase, 3-phase, 4-phase, 5-phase, 6-phase, etc.) to a load through the use of multiple arrays 700, each of which can generate an AC output signal having a different phase angle.

[0083] FIG. 7B is a block diagram depicting a system 100 having two arrays 700-PA and 700-PB coupled together. Each array 700 is one-dimensional, formed by a series connection of N modules 108. The two arrays 700-PA and 700-PB can each generate a single-phase AC signal, with the two AC signals having different phase angles PA and PB (e.g., 180 degrees apart). The IO port 1 of the module 108-1 of each array 700-PA and 700-PB can form or be connected to system IO ports SIO1 and SIO2, respectively, which can then serve as the first output of each array that can supply two-phase power to a load (not shown). Or, alternatively, the ports SIO1 and SIO2 can be connected to supply single-phase power from the two parallel arrays. IO port 2 of module 108-N of each array 700-PA and 700-PB can serve as a second output for each array 700-PA and 700-PB on the opposite end of the array from system IO ports SIO1 and SIO2, which can be tied together at a common node and can optionally be used for an additional system IO port SIO3 that can function as neutral, if desired. This common node can be referred to as a rail, and IO port 2 of module 108-N of each array 700 can be referred to as being on the rail side of the array.

[0084] 7C is a block diagram depicting a system 100 having three arrays 700-PA, 700-PB, and 700-PC coupled together. Each array 700 is one-dimensional, formed by a series connection of N modules 108. The three arrays 700-1 and 700-2 can each generate a single-phase AC signal, with the three AC signals having different phase angles PA, PB, PC (e.g., 120 degrees apart). IO port 1 of module 108-1 of each array 700-PA, 700-PB, and 700-PC can form or connect to system IO ports SIO1, SIO2, and SIO3, respectively, which can then supply three-phase power to a load (not shown). The IO ports 2 of modules 108-N of each array 700-PA, 700-PB, and 700-PC can be coupled together at a common node and can optionally be used for an additional system IO port SIO4 that can function neutrally, if desired.

[0085] 7B and 7C can be extended to systems 100 that generate more phases of power. For example, a non-exhaustive list of additional examples includes a system 100 having four arrays 700, each of which is configured to generate a single-phase AC signal having a different phase angle (e.g., 90 degrees apart), a system 100 having five arrays 700, each of which is configured to generate a single-phase AC signal having a different phase angle (e.g., 72 degrees apart), and a system 100 having six arrays 700, each of which is configured to generate a single-phase AC signal having a different phase angle (e.g., 60 degrees apart).

[0086] The system 100 can be configured such that the arrays 700 are interconnected at electrical nodes between the modules 108 in each array. Figure 7D is a block diagram depicting a system 100 having three arrays 700-PA, 700-PB, and 700-PC coupled together in a combined series and delta arrangement. Each array 700 includes a first series connection of M modules 108, where M is 2 or more, coupled with a second series connection of N modules 108, where N is 2 or more. The delta configuration is formed by the interconnections between the arrays, which can be located at any desired location. In this embodiment, IO port 2 of module 108-(M+N) of array 700-PC is coupled to IO port 2 of module 108-M and IO port 1 of module 108-(M+1) of array 700-PA, IO port 2 of module 108-(M+N) of array 700-PB is coupled to IO port 2 of module 108-M and IO port 1 of module 108-(M+1) of array 700-PC, and IO port 2 of module 108-(M+N) of array 700-PA is coupled to IO port 2 of module 108-M and IO port 1 of module 108-(M+1) of array 700-PB.

[0087] FIG. 7E is a block diagram depicting system 100 having three arrays 700-PA, 700-PB, and 700-PC coupled together in a combined serial and delta arrangement. This embodiment is similar to that of FIG. 7D, except with a different cross-connection. In this embodiment, IO port 2 of module 108-M of array 700-PC is coupled to IO port 1 of module 108-1 of array 700-PA, IO port 2 of module 108-M of array 700-PB is coupled to IO port 1 of module 108-1 of array 700-PC, and IO port 2 of module 108-M of array 700-PA is coupled to IO port 1 of module 108-1 of array 700-PB. The arrangements of FIGS. 7D and 7E can be implemented with as few as two modules in each array 700. The combined delta and series configuration allows for efficient energy exchange between all modules 108 of the system (inter-phase balancing) and the phases of the power grid or load, and also allows for a reduction in the total number of modules 108 in the array 700 to obtain a desired output voltage.

[0088] In the embodiments described herein, it is advantageous for the number of modules 108 to be the same for each array 700 in the system 100, but such is not required and different arrays 700 may have different numbers of modules 108. Furthermore, each array 700 may have modules 108 that are all of the same configuration (e.g., all modules are 108A, all modules are 108B, all modules are 108C, etc.) or different configurations (e.g., one or more modules are 108A, one or more are 108B, one or more are 108C, etc.). Thus, the range of topologies of the system 100 covered herein is broad.

[0089] Control method examples As mentioned, the control of the system 100 can be performed according to various methods, such as hysteresis or PWM. Some examples of PWM include space vector modulation and sinusoidal pulse width modulation, where the switching signals for the converter 202 are generated with a phase shifted carrier technique that continuously rotates the utilization of each module 108 to equally distribute the power between them.

[0090] 8C-8F are plots depicting an exemplary embodiment of a phase-shifted PWM control method that can generate a multi-level output PWM waveform using incrementally shifted two-level waveforms. An X-level PWM waveform can be created by a sum of (X-1) / 2 two-level PWM waveforms. These two-level waveforms can be generated by comparing a reference waveform Vref to a carrier shifted by 360° / (X-1). The carrier is triangular, but the embodiment is not limited to such. A nine-level example (using four modules 108) is shown in FIG. 8C. The carrier is incrementally shifted by 360° / (9-1)=45° and compared to Vref. The resulting two-level PWM waveform is shown in FIG. 8E. These two-level waveforms can be used as switching signals for the semiconductor switches (e.g., S1-S6) of the converter 202. 8E, for a one-dimensional array 700 including four modules 108 each having a converter 202, the 0° signal is for control of S3 of the first module 108-1, the 180° signal is for S6 of the first module 108-1, the 45° signal is for S3 of the second module 108-2, the 225° signal is for S6 of the second module 108-2, the 90 signal is for S3 of the third module 108-3, the 270 signal is for S6 of the third module 108-3, the 135 signal is for S3 of the fourth module 108-4, and the 315 signal is for S6 of the fourth module 108-4. The signal for S3 is complementary to S4, and the signal for S5 is complementary to S6 with sufficient dead time to avoid shoot-through of each half-bridge. FIG. 8F depicts an exemplary single-phase AC waveform resulting from the superposition (addition) of the output voltages from the four modules 108.

[0091] An alternative is to utilize both positive and negative reference signals on the first (N-1) / 2 carriers. A nine-level example is shown in FIG. 8D. In this example, the 0° to 135° switching signal (FIG. 8E) is generated by comparing +Vref with the 0° to 135° carrier of FIG. 8D, and the 180° to 315° switching signal is generated by comparing -Vref with the 0° to 135° carrier of FIG. 8D. However, the logic of comparison in the latter case is reversed. Other techniques, such as state machine decoders, may also be used to generate the gate signals for the switches of the converter 202.

[0092] In embodiments of a multi-phase system, the same carrier can be used for each phase, or the set of carriers can be shifted as a whole for each phase. For example, in a three-phase system with a single reference voltage (Vref), each array 700 can use the same number of carriers with the same relative offset, as shown in Figures 8C and 8D, but the carrier of the second phase is shifted 120 degrees compared to the carrier of the first phase, and the carrier of the third phase is shifted 240 degrees compared to the carrier of the first phase. If different reference voltages are available for each phase, then the phase information can be carried in the reference voltage and the same carrier can be used for each phase. Often the carrier frequency is fixed, but in some exemplary embodiments the carrier frequency can be adjusted, which can help reduce losses in the EV motor under high current conditions.

[0093] An appropriate switching signal can be provided to each module by the control system 102. For example, the MCD 112 can provide Vref and an appropriate carrier signal to each LCD 114, which can then generate the switching signal, depending on which module or modules 108 the LCD 114 controls, or all carrier signals can be provided to all LCDs 114 in the array, and the LCD can select the appropriate carrier signal.

[0094] The relative utilization of each module 108 can be adjusted to perform balancing or based on status information of one or more parameters as described herein. Parameter balancing can involve adjusting utilization to minimize variance of a parameter over time compared to a system in which individual module utilization adjustments are not performed. Utilization can be the relative amount of time a module 108 is discharging when the system 100 is in a discharging state, or the relative amount of time a module 108 is charging when the system 100 is in a charging state.

[0095] As described herein, modules 108 may be balanced relative to other modules in an array 700, which may be referred to as intra-array or intraphase balancing, and different arrays 700 may be balanced relative to each other, which may be referred to as interarray or interphase balancing. Arrays 700 of different subsystems may also be balanced relative to each other. The control system 102 may simultaneously perform any combination of intra-phase balancing, inter-phase balancing, utilization of multiple energy sources within a module, active filtering, and auxiliary load supply.

[0096] FIG. 9A is a block diagram illustrating an exemplary embodiment of an array controller 900 of a control system 102 for a single-phase AC or DC array. The array controller 900 can include a peak detector 902, a divider 904, and an intra-phase (or intra-array) balance controller 906. The array controller 900 can receive as input a reference voltage waveform (Vr) and status information (e.g., state of charge (SOCi), temperature (Ti), capacity (Qi), and voltage (Vi)) for each of the N modules 108 in the array, and generate as output a normalized reference voltage waveform (Vrn) and a modulation index (Mi). The peak detector 902 detects the peak (Vpk) of Vr, which can be specific to the phase in which the controller 900 is operating with and / or without balancing. The divider 904 generates Vrn by dividing Vr by its detected Vpk. The intra-phase balance controller 906 uses Vpk along with status information (eg, SOCi, Ti, Qi, Vi, etc.) to generate a modulation index Mi for each module 108 in the array 700 being controlled.

[0097] The modulation index and Vrn can be used to generate a switching signal for each converter 202. The modulation index can be a number between zero and one, inclusive. For a particular module 108, the normalized reference Vrn can be modulated or scaled by Mi, and this modulated reference signal (Vrnm) can be used as Vref (or -Vref) according to the PWM technique described with respect to Figs. 8C-8F, or according to other techniques. In this manner, the modulation index can be used to control the PWM switching signals provided to the converter switching circuits (e.g., S3-S6 or S1-S6), and thus regulate the operation of each module 108. For example, a module 108 controlled to maintain normal or full operation may receive a Mi of one, a module 108 controlled to operate less than normal or full operation may receive a Mi less than one, and a module 108 controlled to stop power output may receive a Mi of zero. This operation can be performed by the control system 102 in a variety of ways, such as by the MCD 112 outputting Vrn and Mi to the appropriate LCD 114 for modulation and switch signal generation, by the MCD 112 performing modulation and outputting modulated Vrnm to the appropriate LCD 114 for switch signal generation, or by the MCD 112 performing modulation and switch signal generation to output the switch signal directly to the LCD or converter 202 of each module 108. Vrn can be transmitted continuously with Mi transmitted at regular intervals, such as once every period of Vrn or once every minute.

[0098] The controller 906 can use any type or combination of types of status information described herein (e.g., SOC, temperature (T), Q, SOH, voltage, current) to generate Mi for each module 108. For example, using SOC and T, if the SOC is relatively high and the temperature is relatively low compared to other modules 108 in the array 700, the module 108 can have a relatively high Mi. If either the SOC is relatively low or T is relatively high, the module 108 can have a relatively low Mi, resulting in a lower utilization than other modules 108 in the array 700. The controller 906 can determine Mi such that the sum of the module voltages does not exceed Vpk. For example, Vpk can be the sum of the products of the voltages of the sources 206 of each module and Mi for that module (e.g., Vpk=M1V1+M2V2+M3V3...+M N V N etc.) Different combinations of modulation indexes, and therefore respective voltage contributions by the modules, may be used, but the total generated voltage should remain the same.

[0099] The controller 900 can control the operation of the energy sources in each module 108 to balance or converge to a balanced state if not balanced, and / or the temperature of the energy sources or other components (e.g., energy buffers) in each module to balance or converge to a balanced state if not balanced, to the extent that it does not prevent the system from achieving its power output requirements at any time (e.g., during maximum acceleration of the EV). Power flow into and out of the modules can be adjusted so that capacitance differences between sources do not cause SOC deviations. Balancing SOC and temperature can indirectly cause SOH balancing. Voltage and current can be directly balanced if desired, but in many embodiments, the primary objective of the system is to balance SOC and temperature, and balancing SOC can result in voltage and current balancing in a highly symmetrical system where modules have similar capacitance and impedance.

[0100] Since it may not be possible to balance all parameters simultaneously (e.g., balancing one parameter cannot further balance another parameter), a combination of balancing any two or more parameters (SOC, T, Q, SOH, V, I) may be applied with priority given to one over the other depending on the requirements of the application. Balancing priority may be given to SOC over the other parameters (T, Q, SOH, V, I), with an exception being made if one of the other parameters (T, Q, SOH, V, I) reaches a severe imbalance state outside of thresholds.

[0101] Balancing between arrays 700 of different phases (or arrays of the same phase, e.g., if parallel arrays are used) can be performed simultaneously with intra-phase balancing. FIG. 9B depicts an exemplary embodiment of an Ω-phase (or Ω-array) controller 950 configured for operation in an Ω-phase system 100 having at least an Ω-array 700, where Ω is any integer greater than 1. The controller 950 can include one inter-phase (or inter-array) controller 910 and intra-Ω-phase balance controllers 906-PA...906-PΩ for phases PA-PΩ, as well as peak detectors 902 and dividers 904 (FIG. 9A) for generating normalized references VrnPA-VrnPΩ from each phase-specific reference VrPA-VrPΩ. The intra-phase controller 906 can generate Mi for each module 108 of each array 700, as described with respect to FIG. 9A. The inter-phase balance controller 910 is configured or programmed to balance aspects of the modules 108 across the multi-dimensional system, for example, between arrays of different phases. This may be accomplished by injecting a common mode into the phases (e.g., neutral point shifting), or by the use of interconnection modules (as described herein), or both. Common mode injection involves introducing phase and amplitude shifts into the reference signals VrPA-VrPΩ to compensate for imbalances in one or more arrays to generate normalized waveforms VrnPA-VrnPΩ, as further described in International Application No. PCT / US20 / 25366, which is incorporated herein.

[0102] The controllers 900 and 950 (as well as the balance controllers 906 and 910) may be implemented in hardware, software, or a combination thereof within the control system 102. The controllers 900 and 950 may be implemented within the MCD 112, may be partially or fully distributed among the LCD 114, or may be implemented as separate controllers independent of the MCD 112 and the LCD 114.

[0103] Interconnect (IC) Module Example Modules 108 can be connected between modules of different arrays 700 for the purpose of exchanging energy between arrays, or for the purpose of acting as a source for auxiliary loads, or both. Such modules are referred to herein as interconnect (IC) modules 108IC. The IC modules 108IC can be implemented in any of the module configurations (108A, 108B, 108C) already described, as well as other configurations described herein. The IC modules 108IC can include any number of one or more energy sources, optional energy buffers, switch circuits for supplying energy to one or more arrays and / or powering one or more auxiliary loads, control circuits (e.g., local control devices), and monitoring circuits for collecting status information about the IC module itself or its various loads (e.g., SOC of the energy source, temperature of the energy source or energy buffer, capacity of the energy source, SOH of the energy source, voltage and / or current measurements associated with the IC module, voltage and / or current measurements associated with the auxiliary loads, etc.).

[0104] FIG. 10A is a block diagram depicting an exemplary embodiment of a system 100 capable of generating Ω-phase power with Ω arrays 700-PA through 700-PΩ, where Ω can be any integer greater than 1. In this and other embodiments, IC module 108IC can be located on the rail side of array 700 such that the array 700 to which module 108IC is connected (in this embodiment, arrays 700-PA through 700-PΩ) is electrically connected between module 108IC and the output to the load (e.g., SIO1 through SIOΩ). Here, module 108IC has an ΩIO port for connection to IO port 2 of each module 108-N of array 700-PA through 700-PΩ. In the configuration depicted here, module 108IC can perform phase-to-phase balancing by selectively connecting one or more energy sources of module 108IC to one or more of arrays 700-PA through 700-PΩ (or to none or equally to all outputs if phase-to-phase balancing is not required). The system 100 can be controlled by a control system 102 (not shown, see FIG. 1A).

[0105] FIG. 10B is a schematic diagram depicting an exemplary embodiment of the module 108IC. In this embodiment, the module 108IC includes an energy source 206 connected to an energy buffer 204, which is connected to a switch circuit 603. The switch circuit 603 can include switch circuit units 604-PA to 604-PΩ for independently connecting the energy source 206 to each of the arrays 700-PA to 700-PΩ. Various switch configurations can be used for each unit 604, which in this embodiment is configured as a half-bridge with two semiconductor switches S7 and S8. Each half-bridge is controlled by a control line 118-3 from the LCD 114. This configuration is similar to the module 108A described with respect to FIG. 3A. As described with respect to the converter 202, the switch circuit 603 can be configured in any arrangement and with any switch type (e.g., MOSFET, IGBT, silicon, GaN, etc.) suitable for the requirements of the application.

[0106] The switch circuit unit 604 is coupled between the positive and negative terminals of the energy source 206 and has an output connected to an IO port of the module 108 IC. The units 604-PA to 604-PΩ are controlled by the control system 102 to switch the voltage +V IC or -V ICmay be selectively coupled to respective module I / O ports 1-Ω. The control system 102 may control the switch circuit 603 according to any desired control technique, including the PWM and hysteresis techniques described herein. Here, the control circuit 102 is implemented as an LCD 114 and an MCD 112 (not shown). The LCD 114 may receive monitoring data or status information from monitoring circuitry of the module 108 IC. This monitoring data and / or other status information derived from this monitoring data may be output to the MCD 112 for use in system control as described herein. The LCD 114 may also receive timing information (not shown) for purposes of synchronizing the modules 108 of the system 100 with one or more carrier signals (not shown), such as sawtooth signals used in the PWM (FIGS. 8C-8D).

[0107] In the case of inter-phase balancing, proportionally more energy from the source 206 can be delivered to any one or more of the arrays 700-PA through 700-PΩ that are relatively low charged compared to the other arrays 700. The delivery of this supplemental energy to a particular array 700 allows the energy output of those cascaded modules 108-1 through 108-N within that array 700 to be reduced relative to the un-fed phase arrays.

[0108] For example, in some exemplary embodiments applying PWM, the LCD 114 may be configured to receive a normalized voltage reference signal (Vrn) (from the MCD 112) for each of the one or more arrays 700 to which the module 108 IC is coupled, e.g., VrnPA-VrnPΩ. The LCD 114 may also receive modulation indexes MiPA-MiPΩ for the switch units 604-PA-604-PΩ for each array 700, respectively, from the MCD 112. The LCD 114 may modulate (e.g., multiply) each respective Vrn with a modulation index for the switch section directly coupled to that array (e.g., multiply VrnA by MiA) and then utilize a carrier signal to generate a control signal for each switch unit 604. In other embodiments, the MCD 112 may perform the modulation and output a modulated voltage reference waveform for each unit 604 directly to the LCD 114 of the module 108 IC. In yet other embodiments, all processing and modulation may occur by a single control entity that may output control signals directly to each unit 604 .

[0109] This switching can be modulated so that power from the energy source 206 is provided at appropriate intervals and durations to the array 700. Such a method can be implemented in a variety of ways.

[0110] Based on collected status information for the system 100, such as the current capacity (Q) and SOC of each energy source in each array, the MCD 112 can determine an aggregate charge for each array 700 (e.g., the aggregate charge for an array can be determined as the sum of the capacity vs. SOC for each module in that array). The MCD 112 can determine whether a balanced or unbalanced condition exists (e.g., by use of relative difference thresholds and other metrics described herein) and generate modulation indices MiPA through MiPΩ for each switch unit 604-PA through 604-PΩ accordingly.

[0111] During balanced operation, Mi for each switch unit 604 can be set to a value that causes each array 700 to be supplied with the same or similar amount of net energy over time by the energy source 206 and / or energy buffer 204. For example, Mi for each switch unit 604 can be the same or similar and can be set to a level or value that causes the module 108IC to perform a net or time-averaged discharge of energy to one or more arrays 700-PA to 700-PΩ during balanced operation, such that the module 108IC discharges at the same rate as other modules 108 in the system 100. In some embodiments, Mi for each unit 604 can be set to a level or value that causes no net or time-averaged discharge of energy (zero net energy discharge) during balanced operation. This can be useful when the module 108IC has a lower aggregate charge than other modules in the system.

[0112] When an imbalance occurs between the arrays 700, the modulation index of the system 100 can be adjusted to converge toward a balanced state or to minimize further divergence. For example, the control system 102 can cause a module 108 to discharge more into the array 700 at a lower charge than others, and cause the modules 108-1 to 108-N of the lower array 700 to discharge relatively less (e.g., on a time-averaged basis). The relative net energy contributed by the module 108 increases compared to the modules 108-1 to 108-N of the supported array 700, and compared to the amount of net energy module 108 contributing to other arrays. This can be accomplished by increasing Mi for the switch unit 604 supplying that lower array 700, and by decreasing the modulation index of the modules 108-1 to 108-N of the lower array 700 in a manner that maintains Vout for that lower array at an appropriate or required level, while keeping the modulation index for the other switch units 604 supplying other higher arrays relatively unchanged (or decreased).

[0113] 10A-10B may be used alone to provide inter-phase or inter-array balancing for a single system, or may be used in combination with one or more other modules 108IC, each having an energy source and one or more switch portions 604 coupled to one or more arrays. For example, a module 108IC having an Ω switch portion 604 coupled to an Ω different array 700 may be combined with a second module 108IC having one switch portion 604 coupled to an array 700, such that the two modules are combined to service a system 100 having an Ω+1 array 700. Any number of modules 108IC may be combined in this manner, each coupled to one or more arrays 700 of the system 100.

[0114] Further, the IC module can be configured to exchange energy between two or more subsystems of the system 100. FIG. 10C is a block diagram depicting an example embodiment of the system 100 having a first subsystem 1000-1 and a second subsystem 1000-2 interconnected by an IC module. Specifically, the subsystem 1000-1 is configured to supply three-phase power PA, PB, and PC to a first load (not shown) via system I / O ports SIO1, SIO2, and SIO3, and the subsystem 1000-2 is configured to supply three-phase power PD, PE, and PF to a second load (not shown) via system I / O ports SIO4, SIO5, and SIO06, respectively. For example, the subsystems 1000-1 and 1000-2 can be configured as different packs supplying power to different motors of an EV or as different racks supplying power to different microgrids.

[0115] In this embodiment, each module 108IC is coupled to the first array of the subsystem 1000-1 (via IO port 1) and the first array of the subsystem 1000-2 (via IO port 2), and each module 108IC can be electrically connected to the other modules 108IC via I / O ports 3 and 4, which are coupled to the energy source 206 of each module 108IC as described with respect to the module 108C in FIG. 3C. This connection places the sources 206 of the modules 108IC-1, 108IC-2, and 108IC-3 in parallel, and thus the energy stored and supplied by the modules 108IC is pooled together by this parallel arrangement. Other arrangements, such as deep connections, can also be used. The modules 108IC are housed in a common enclosure of the subsystem 1000-1, but the interconnection module can be outside the common enclosure and physically located as an independent entity between the common enclosures of both subsystems 1000.

[0116] Each module 108IC has a switch unit 604-1 coupled to IO port 1 and a switch unit 604-2 coupled to I / O port 2, as described with respect to FIG. 10B. Thus, in the case of balancing between subsystems 1000 (e.g., pack-to-pack balancing or rack-to-rack balancing), a particular module 108IC can supply relatively more energy to one or both of the two arrays to which it is connected (e.g., module 108IC-1 can supply array 700-PA and / or array 700-PD). The control circuitry can monitor the relative parameters (e.g., SOC and temperature) of the arrays of the different subsystems and adjust the energy output of the IC modules to compensate for imbalances between arrays or phases of the different subsystems in the same manner described herein as compensating for imbalances between two arrays of the same rack or pack. Because all three modules 108IC are in parallel, energy can be efficiently exchanged between any and all arrays of the system 100. In this embodiment, each module 108 IC supplies two arrays 700, although other configurations can be used including a single IC module for all arrays in system 100 and one dedicated IC module for each array 700 (e.g., six IC modules for six arrays with each IC module having one switch unit 604). In all cases with multiple IC modules, the energy sources can be coupled together in parallel to share energy as described herein.

[0117] In systems with inter-phase IC modules, inter-phase balancing can also be performed with neutral point shifting (or common mode injection), as described above. Such a combination allows for more robust and flexible balancing under a wider range of operating conditions. System 100 can determine the appropriate circumstances to perform inter-phase balancing with a combination of only neutral point shifting, only inter-phase energy injection, or both simultaneously.

[0118] The IC module can also be configured to supply power to one or more auxiliary loads 301 (at the same voltage as source 206) and / or one or more auxiliary loads 302 (at a stepped-down voltage from source 302). FIG. 10D is a block diagram illustrating an example embodiment of a three-phase system 100A having two modules 108IC connected to perform phase-to-phase balancing and supply auxiliary loads 301 and 302. FIG. 10E is a schematic diagram illustrating this example embodiment of the system 100 with emphasis on modules 108IC-1 and 108IC-2. Here, the control circuit 102 is again implemented as an LCD 114 and MCD 112 (not shown). The LCD 114 can receive monitoring data from the modules 108IC (e.g., SOC of ES1, temperature of ES1, Q of ES1, voltages of auxiliary loads 301 and 302, etc.) and can output this and / or other monitoring data to the MCD 112 for use in system control as described herein. Each module 108IC may include a switch portion 602A (or 602B as described with respect to FIG. 6C) for each load 302 being supplied by that module, and each switch portion 602 may be controlled independently or based on a control input from the MCD 112 to maintain a required voltage level for the load 302 through the LCD 114. In this embodiment, each module 108IC includes switch portions 602A connected together to supply one load 302, although such is not required.

[0119] FIG. 10F is a block diagram depicting another exemplary embodiment of a three-phase system configured to power one or more auxiliary loads 301 and 302 having modules 108IC-1, 108IC-2, and 108IC-3. In this embodiment, modules 108IC-1 and 108IC-2 are configured in the same manner as described with respect to FIGS. 10D-10E. Module 108IC-3 is configured in a purely auxiliary role and does not actively inject voltage or current into any array 700 of system 100. In this embodiment, module 108IC-3 can be configured like module 108C of FIG. 3B, having converters 202B,C (FIGS. 6B-6C) with one or more auxiliary switch portions 602A, but omitting switch portion 601. Accordingly, one or more energy sources 206 of module 108IC-3 are interconnected in parallel with those of modules 108IC-1 and 108IC-2, and thus this embodiment of system 100 is configured with additional energy to supply auxiliary loads 301 and 302, as well as to maintain the charge of source 206A of modules 108IC-1 and 108IC-2 via the parallel connection with source 206 of module 108IC-3.

[0120] The energy source 206 of each IC module can be, but is not required to be, the same voltage and capacity as the energy sources 206 of the other modules 108-1 through 108-N in the system. For example, a relatively high capacity may be desirable in an embodiment where one module 108 IC applies energy to multiple arrays 700 (FIG. 10A) to allow the IC module to discharge at the same rate as the modules in the phased array itself. If the module 108 IC is also supplying an auxiliary load, an even larger capacity may be desirable to allow the IC module to supply the auxiliary load and discharge at the same rate relatively as the other modules.

[0121] Examples of second life energy sources The energy source 206 described herein may be used in the system 100 described herein in both first-life and second-life applications. The first-life of the source 206 is the original application in which the source 206 is used. For example, a first-life application is the first implementation in which the source 206 is used by the original customer of the source 206 after their initial manufacture (not refurbishment). The user of the source 206 would typically have received the source 206 from a manufacturer, distributor, or original equipment manufacturer (OEM) in its first life. The battery 206 used in the first-life application will typically have the same electrochemistry (e.g., the same variant of lithium-ion electrochemistry (e.g., LFP, NMC)), the same nominal voltage, and will have minimal (e.g., 5% or less) capacity variation across the pack or system. Using an energy storage system with battery 206 in its first life application will result in battery 206 having a longer life in its first life application, and when removed from its first life application, battery 206 will be similar in terms of capacity degradation than a battery from a first life application without the energy storage system.

[0122] As used herein, a "second life" application refers to any application or implementation after the first life application (e.g., second implementation, third implementation, fourth implementation, etc.) of the source 206. A second life energy source refers to any energy source (e.g., a battery or HED capacitor) implemented in the second life application of that source.

[0123] An example of a first life application of the battery 206 is in an energy storage system for an EV. Then, at the end of its life (e.g., after 100,000 miles of driving or after the batteries in the battery pack have degraded by a threshold amount), the battery 206 may be removed from the battery pack, optionally refurbished and tested, and then implemented in a second life application that may be used, for example, in a stationary energy storage system (e.g., residential, commercial, or industrial energy buffering, energy buffering for EV charging stations, renewable sources (e.g., wind, solar, hydro), energy buffering, etc.) or another mobile energy storage system (e.g., battery pack for an electric vehicle, bus, train, or truck). Similarly, the first life application may be a first stationary application, and the second life application may be a stationary application or a mobile application.

[0124] For the second life application, the sources 206 may be selected and / or utilized by the system 100 to minimize (or at least reduce) any differences in initial capacity and nominal voltage. For example, sources 206 having a capacity difference of 5% or more may be included in the system 100 and may operate to provide energy to a load. In another example, an operator or an automated system may select sources 206 for the system 100 having a capacity difference within a threshold amount, for example, to reduce the initial capacity difference between the sources 206 of the system. If a module 108 is suitable for both the first life application and the second life application (e.g., with or without reconfiguration), the module 108 may be selected for the second life application based on the capacity difference of the sources 206 of the module 108.

[0125] The system 100 can individually adjust the utilization of each source 206 such that the sources 206 in the system 100 or the packs of the system 100 are relatively balanced in terms of SOC or total charge (SOC x capacity) when the packs or system 100 are being discharged, even though the sources 206 in the system 100 can have a wide variety of capacities. Similarly, the system 100 can maintain balance when the packs or system 100 are being charged. The sources 206 can vary not only in terms of capacity, but also in nominal voltage, power rating, electrochemical type (e.g., a combination of LFP and NMC batteries), etc. Thus, the system 100 can be used such that every module 206 in the system 100 or each pack of the system 100 is a second-life energy source (or a combination of first-life energy sources and second-life energy sources are used) with various combinations of different characteristics.

[0126] In one example, the system 100 can include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having an energy capacity variation of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0127] In another example, the system 100 can include a second energy life source 206 (and, optionally, one or more first life energy sources 206) having a variation in energy content per mass density of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0128] In another example, the system 100 can include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having a variation in peak power per mass density of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0129] In another example, the system 100 may include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having a nominal voltage variation of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0130] In another example, the system 100 can include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having an operating voltage range variation of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0131] In another example, the system 100 can include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having a variation in maximum specified current rise time of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0132] In another example, the system 100 can include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having a variation in specified maximum current of 2% or more, 5% or more, 10% or more, 15% or more, 20% or more, or 25% or more, 30% or more, 5-30%, 10-30%, and / or 20-30%.

[0133] A variation of X% (e.g., 5% or more, or 5-30%) may be satisfied by a variation in capacity between the module 108 in the system 100 having the highest value for that parameter and the module 108 having the lowest value for that parameter. For example, a variation in capacity of 5% or more may be satisfied by a system 100 in which the module 108 having the lowest capacity source 206 has a capacity that is 95% or less of the capacity of the module 108 having the highest capacity source 206. For each and every embodiment and parameter disclosed herein, the time at which a system 100 having one or more second life sources will satisfy the X% variation in parameter condition may be upon installation of the system 100, upon commissioning of the system 100, after replacing one source 206 with another source 206, after 10 hours or more operation of the system 100, after 1000 hours or more operation of the system 100, and / or after 10,000 hours or more operation of the system 100. For example, even though no capacity fluctuations were present during commissioning, a capacity fluctuation of 5% or more may occur after 1000 hours of operation of system 100. This reflects the ability of an embodiment of system 100 to continue to operate with and account for a capacity difference between sources 206 that increases over the course of operating time.

[0134] In another example, the system 100 may include a second life energy source 206 (and, optionally, one or more first life energy sources 206) having variations in electrochemical type (e.g., lithium ion batteries with non-lithium ion batteries, or different lithium ion batteries (e.g., NMC, LFP, LTO, or any combination of other lithium ion battery types).

[0135] The system 100 can include a second-life energy source 206 (and, optionally, one or more first-life energy sources 206) having any combination of the characteristics provided in the preceding examples.

[0136] fast charging Exemplary embodiments related to fast charging techniques for energy sources using pulse heating and / or pulse charging techniques are now described herein. Although the embodiments are primarily described in the context of an energy source 206 being a battery, the embodiments are also applicable to other types of energy sources (e.g., high energy density capacitors and fuel cells). The embodiments can be applied to charge batteries having a single cell, batteries having multiple cells (e.g., connected in series, parallel, or a combination thereof, sometimes referred to as battery modules), and systems having multiple battery modules (e.g., connected in series, parallel, or a combination thereof) (e.g., battery packs).

[0137] Examples of battery types suitable for use with the present subject matter include solid-state batteries, liquid electrotype based batteries, liquid phase batteries, and flow batteries such as lithium (Li) metal batteries, Li-ion batteries, Li-air batteries, sodium-ion batteries, potassium-ion batteries, magnesium-ion batteries, alkaline batteries, nickel metal hydride batteries, nickel sulfate batteries, lead acid batteries, zinc-air batteries, etc. Some examples of Li-ion battery types include Li cobalt oxide (LCO), Li manganese oxide (LMO), Li nickel manganese cobalt oxide (NMC), Li iron phosphate (LFP), Li nickel cobalt aluminum oxide (NCA), and Li titanate (LTO).

[0138] Although not required to be used in any particular configuration of an energy storage system, the embodiments of the system 100 described herein may particularly benefit from use with this embodiment of fast charging. When used with an embodiment of the system 100 for charging an energy source 206 in a , the converter 202 of each module 108 is independently controlled to apply a positive pulse, a zero pulse, or a negative pulse from the power connection 110 to the source 206. The AC or DC signal applied to the power connection 110 may be fed back to the source 206 in a reverse manner to the process described herein to generate a superposition of all output pulses from all modules 108. Each converter 202 may switch at a frequency of more than 100 Hz to apply pulses of, for example, 5 milliseconds (ms) or less with a 50% duty cycle. Longer or shorter pulse durations with different duty cycles may also be used. Such pulsing functionality allows for charging and / or heating the energy source as described herein.

[0139] The converter 202 may be controlled using a control system that applies pulse width modulation, hysteresis, or another technique that seeks to utilize all modules equally over time. Each module 108 may monitor the status of its energy source 206 (e.g., state of charge (SOC), temperature, voltage, current, etc.) and feed this monitored information back to the control system 102, which may adjust the charge utilization of each module 108 individually to maintain balance or converge toward a balanced state for selected parameters or parameters to be balanced (e.g., SOC and / or temperature).

[0140] The cascaded topology of the system 100 allows the charging voltage or current from the charging source to be split between the energy sources as needed to implement charging schemes of various sophistication. For example, the voltage (or current) can be applied in a pulsed manner, where some sources 206 are charged at a particular time and others are not, but generally provided that the total voltage applied to the sources 206 (and other charging sinks in the system) is equal to the DC or AC voltage provided to the system 100 by the charging sources at that time. The voltage and duration of the applied pulses (and the duration of the rest time between pulses) can be varied and timed based on the state of each module 108's sources 206, as monitored by those sources 206 (e.g., the monitoring circuitry 208 and the LCD 114). Thus, the voltage division between the modules 108 allows the sources 206 of the modules 108 to both charge and rest as needed.

[0141] The embodiments can be used to charge the charging source 206 with various degrees of granularity. For example, the battery module can be pulsed as a whole, e.g., one pulse can be applied to all the cells that make up the battery module. Alternatively, additional switching circuitry can be included for individual cells (e.g., in addition to the configuration shown for the converter 202) so that each cell of the battery module can be pulsed independently. For example, a system 100 having N battery modules, each having M cells, can be configured with N×M converters or switch circuits. Other levels of granularity are possible, such as the ability to pulse charging groups of cells within each battery module (e.g., the cells are divided into two groups that can each be charged independently, such that the system has 2N converters or switch circuits). Control of the switch circuits of the various battery modules and / or cells can be performed by a control system 102 communicatively coupled to the system module 108 (e.g., the MCD 112 communicatively coupled to the LCD 114).

[0142] Exemplary embodiments of the pulse charging and heating technique Exemplary embodiments are provided herein relating to pulse charging of energy sources at improved rates to achieve fast or rapid charging. Exemplary embodiments relate to applying voltage or current pulses to a battery to raise the temperature of the battery through localized heating, applying voltage or current pulses to a battery to charge the battery, applying a constant (non-pulsed) voltage or constant current to a battery to charge the battery at a higher temperature, monitoring the battery for a state of health during charging, and any combination thereof. The embodiments described herein can enable stationary and mobile energy storage systems to be charged at a wide range of C-rates, provided certain voltage and temperature constraints on the battery cells are not exceeded. For example, embodiments can enable an EV with 100 kilowatt-hours (kWh) of storage capacity to be charged from zero to 80% capacity in 10 minutes (or less) without substantial capacity degradation over the rated life of the battery pack.

[0143] FIG. 11A is a plot depicting a framework for describing several exemplary embodiments of a charging protocol 1100 for charging a battery source 206 from a relatively low state of charge (SOC) to a substantial SOC in a short time frame of less than 15 minutes. FIG. 11B is a plot of an embodiment of the protocol 1100 with exemplary values ​​applied. The charging protocol 1100 described with respect to FIGS. 11A-11B (and elsewhere herein) can be applied to a battery having only a single cell, or a battery module having two or more cells (e.g., 2-100 cells), and can be implemented by charging and switching circuitry local to the external charging source. For example, the charger can sense the temperature (e.g., surface) and voltage response of the entire battery device and adjust the application of preheat and charging signals accordingly. While such an approach is possible for charging a single cell, a battery module having multiple cells, or even an entire system (e.g., a battery pack), the present approach does not allow for fine-grained control of the preheat and charging process as applied to individual cells within a battery module and / or individual battery modules within a system.

[0144] To provide more granular control, the protocol 1100 can also be applied within a cascaded modular energy storage system 100 such as that described herein, where each module 108 includes a battery 206 that may be only a single cell or may include more than one cell (e.g., 2-100 cells), and the number of modules 108 may be two or more (e.g., 2-1000 modules 108). The converters 202 of each module 108 may be independently controlled such that the protocol 1100 may be independently executed by each module 108 of the system 100, as described herein. For example, considering a battery pack having 12 modules 108, each having a battery 206 that includes 12 cells, the protocol 1100 may be independently applied by each module 108 to charge each battery 206 having 12 cells in 15 minutes or less, and thus, charge the entire battery pack in the same or similar time. The condition of the batteries 206 in the system 100 will change and the charging time for each battery 206 may vary because embodiments may adjust the charging rate based on feedback from each battery 206. Some batteries 206 may be at 2-3% SOC while other batteries will be at or near 0% SOC or some percentage in between at the beginning of the charging cycle. Some batteries 206 may have a higher capacity than others and will require longer to reach the desired SOC. Some batteries 206 may show signs of degradation or other characteristics during charging that require the charging process to be slowed.

[0145] To enable discussion of protocol 1100 in more detail, Figures 12A-12F will be considered to provide context for the properties and structure of a battery cell. Figure 12A is a cross-sectional view of a generalized lithium ion battery cell 1200. The cell 1200 includes a repeating layered structure, with each layer including an anode 1201 and a cathode 1202 with a separator 1203 therebetween. Each anode 1201 includes an anode material 1204 having an electrolyte 1208 interposed therein and a current collector 1205 positioned therein. Similarly, each cathode 1202 includes a cathode material 1206 having an electrolyte 1209 interposed therein and a current collector 1207 positioned therein.

[0146] 12B is an illustration depicting an enlarged anode 1201 and cathode 1202 diagram that lists examples of degradation modes that may occur within a typical lithium-ion battery cell. Each of the listed degradation modes may be caused directly or indirectly by application of excessive voltages to the anode and cathode, and by charging at excessive temperatures. Exemplary embodiments described herein aim to limit operation at excessive voltages and excessive temperatures, and therefore limit these degradation modes.

[0147] By applying high current pulses to a battery cell, the cell may exhibit overvoltages that are distributed between the cathode, anode, and the cell itself. FIG. 12C is a graph depicting an example voltage on a lithium-ion cell over a range of SOCs, showing the components of the voltage due to the cathode, anode, and cell. As the state of charge on the cell increases, the allowable or available overvoltage range of the anode and cathode decreases. Graphite anodes typically exhibit a smaller allowable overvoltage range than cathodes over all states of charge, and thus anode overvoltages may be a major constraint when applying relatively large currents for charging. Voltage response analysis may be used to determine the magnitude of the overvoltages on the anode and cathode, and accordingly, the magnitude and frequency of the charging pulses may be maintained, increased, or decreased to remain within the allowable range. The embodiments herein may be applied such that the current decreases as the cell is charged at any stage 1110, 1120, 1130.

[0148] FIG. 12D is an electrical schematic model of a battery cell 1200. The anode has an ohmic component (η* ohmic ) and electrochemical interface components (V EC INTERFACE ) indicates the voltage drop including η* ohmic is the ohmic resistance of the anode (R ohmic ) is determined by the magnitude of V EC INTERFACE is the activation impedance (or charge transfer impedance) when the cell is equilibrated (R CT ) and the anodic double layer sheet capacitance (C DL The increased diffusion-based charge transfer impedance (R Warburg ) (if not balanced) and is determined by η* act is R CT and R Warburg is the activation-based voltage drop across the cathode. The cathode is modeled similarly, but has its own characteristic values. The electrolyte also has an ohmic resistance (R ohmic electrolyte ) is determined by the voltage (V ohmicelectrolyte ) drop. Both the anode and cathode have a frequency dependent inductance L elec Shows.

[0149] The voltage drop across the anode is the voltage due to the ohmic resistance (η* ohmic ) and the voltage due to the electrochemical interface (η* act ), and the voltage due to the open circuit voltage change from diffusion (η* Nernst ) is an accumulation of

[0150] FIG. 12E is a Nyquist plot depicting an example impedance spectroscopic response 1210 of a lithium-ion cell. The impedance response 1210 depends on the charge level of the lithium-ion cell and becomes more compact as the charge level increases. The real impedance is primarily determined by R CT and R Warburg The imaginary component increases by C DL For small or zero frequency charging signals, the impedance response is near the top right of this plot, and the battery cell exhibits relatively high real and imaginary impedances, and therefore a relatively high voltage draw across the anode, which makes it difficult to stay within the allowable anode overvoltage region as higher currents are passed through the battery, shortening the charging time. As the frequency of the charging pulses increases, the impedance response becomes more like a purely real impedance R with a low imaginary component and a relatively low voltage drop across the anode. ohmic The threshold frequency (ω T ), the inductance of the battery cells, battery modules (if present), battery pack (if present), and other circuitry downstream of the charger begins to substantially block current flow. T At frequencies below but within region 1215, relatively high currents can be passed through the battery without exceeding the allowable anode overvoltage range, thereby allowing for faster charging times.

[0151] 12F is a plot of voltage and current versus time depicting an exemplary voltage response 1212 to a stimulation signal in the form of a current pulse 1214 applied to a lithium-ion cell, where the lithium-ion cell is equilibrated prior to application of the pulse 1214 and reaches a resting voltage E at iteration n. 0 Nernst The application of pulse 1214 creates an ohmic resistance (η 0 ohmic ) and cell activation (η 0 act ) which continues until application of pulse 1214 is stopped. The application of the charge pulse, which drives the electrochemical reaction over time, causes a concentration change in the cell due to diffusion, and the cell concentration approaches the equilibrium concentration c 0 R From the diffusion-induced new concentration c* R Referring back to FIG. 12F, during the period T_fall (e.g., less than 150 ms, such as about 50-100 ms), the voltage response changes to ohmic component η* ohmic Then, the active component η* act The rest voltage E* Nernst After T_fall, the battery cell concentration again drops to E 0 Nernst This voltage change slowly equilibrates towards η* Nernst Denoted as: Instantaneous η* ohmic The voltage drop across the EC interface is η 0 act and the voltage change due to the concentration shift η* conc V is the sum of EC INTERFACE It is shown as:

[0152] 11A-11B, the protocol 1100 can have three phases: a preheat phase 1110, a first charging phase 1120, and a second charging phase 1130. Energy for the preheat and charging signals applied to the battery 206 can be provided from a charging source external to the system (e.g., the grid or a charging station) or, in some cases, can be provided internally, such as through a second source 206B. Here, the pulse preheat phase 1110 can last for a set duration (time_0-time_1) or until a first temperature threshold (temp_1) is reached. In FIG. 11B, the preheat phase 1110 is applied until the battery reaches 30° C., which occurs after about 1 minute.

[0153] The preheat phase 1110 involves applying a preheat pulse signal 1112 as a train or sequence of pulses, each pulse optionally alternating from a charge pulse (negative current) to a discharge pulse (positive current) of equal or nearly equal duration with a time gap between application of the charge and discharge pulse pair. Figures 11C-11D are current versus time graphs depicting an exemplary embodiment of a preheat pulse train 1112 oscillating between a positive preheat current (+Iph) and an equal but opposite negative preheat current (-Iph) with and without a time gap, respectively.

[0154] The preheat stage 1110 can achieve localized heating by increasing the temperature of the anode current collector 1205, the cathode current collector 1207, and the electrolyte 1209 (FIG. 12A) without activating an electrochemical reaction. In many embodiments, the frequency (f preheat ) according to equation (1), (1)f AL ,f CL >f preheat >f A Main ,f A Side ,f C Main ,f C Side In the formula, f ALis the characteristic frequency, given by (2), at which the inductance on the anode begins to significantly affect the current flow for a particular application, and f CL is the characteristic frequency given by (3) at which the inductance on the cathode begins to significantly affect the current flow for a particular application, and f A Main is the characteristic frequency of the main reaction, which is the intercalation reaction of lithium ions on the anode, given by (4), and f A Side is the characteristic frequency of the side reaction on the anode given by (5), and f C Main is the characteristic frequency of the main reaction, which is the intercalation reaction of lithium ions on the cathode, given by (6), and f C Side is the characteristic frequency of the side reaction on the cathode, given by (7). (2)f AL <(R ohmic A ) / 2πL A (3)f CL <(R ohmic C ) / 2πL C (4)f A Main >1 / [2π(R CT Main +R Warburg Main ) C DL ] (5)f A Side >1 / [2π(R CT Side +R Warburg Side ) C DL ] (6)f C Main >1 / [2π(R CT Main +R Warburg Main ) C DL ] (7)f C Side >1 / [2π(R CT Side +R Warburg Side ) C DL ]

[0155] In each of (1)-(7), frequencies chosen far from the constraints can provide increased benefit. For example, f AL , f CLf preheat The selection of makes it possible to suppress the induced voltage component in order to avoid voltage noise.

[0156] The preheat signal 1112 may be a single frequency, with each pulse having a rectangular or nearly rectangular shape (as visualized in the time domain). In other embodiments, the preheat signal 1112 may be implemented in a more complex manner with multiple frequency components, such as a primary pulse train and a secondary pulse, in the frequency range of 1 Hertz (Hz) to 1 Megahertz (Mhz). The frequency of the preheat signal 1112 is chosen such that the voltage drop occurs primarily through the electrolyte impedance and the current collector impedance, rather than through the charge transfer impedance. In various embodiments, the preheat signal 1112 has a frequency range of 100 Hz to 100 kilohertz (kHz).

[0157] The pre-heating stage 1110 induces a temperature rise in a localized region within the battery cell by generating heat through an ohmic impedance to heat the active material while bypassing activation of electrochemical reactions such as side reactions (e.g., electrolyte decomposition, active material decomposition, lithium coating) or the main electrochemical reaction (e.g., lithiation). These reactions are preferably bypassed so that they do not substantially occur (within reasonable tolerances as identified by those skilled in the art that allow long-term functional operation in the respective commercial, research, or industrial applications). Stage 1110 may be performed to heat the cell until the activation impedance and total impedance are small enough so that the overvoltage on the anode drives the electrochemical reaction rather than the lithium coating. Stage 1110 thus allows rapid heating of the electrochemical interface and bulk material temperature control, allowing subsequent charging without causing damage to the anode and cathode materials due to side reactions or material stresses due to rapid degradation (e.g., lithiation or delithiation).

[0158] The preheating stage 1110 may be applied until all cells of the source 206 reach a minimum temperature threshold, provided that no cell exceeds the maximum temperature threshold. If a cell reaches the maximum threshold, the preheating stage 1110 may be slowed or stopped, or the protocol 1100 may transition to the next stage (first charging stage 1120 or second charging stage 1130) as described herein. The cell temperature may be measured directly using a temperature sensor (e.g., infrared) or indirectly (e.g., temperature within a subgroup of cells or proximate to the cells). Alternatively, or in combination with direct sensing, the temperature of one or more cells, including all cells, may be measured using a single sensor (e.g., infrared image of multiple cells). The temperature may also be inferred, optionally based on data collected from previously characterized cells and with reference to other indirect metrics (e.g., voltage, current, impedance), through the use of models or look-up tables. The temperature thresholds for this and other stages are preferably correlated to the internal temperature of the cells in which the electrolyte and active materials are located. Thus, if the surface temperature of the battery cells is measured (eg, using a thermistor or optical device), a threshold is set for a surface temperature that correlates with the desired internal cell temperature based on an estimate, look-up table, or model.

[0159] The preheating stage 1110 raises the temperature of the battery 206 to a first temperature threshold, which in the example of FIG. 11B is 30 degrees Celsius (C) measured on the cell surface. The temperature threshold may depend on the battery type, and may be, for example, 25-70° C. (inclusive) for a lithium-ion battery. In other embodiments, the preheating stage 1110 may last for a predetermined duration (time_0-time_1), such as less than 1 minute, 1 minute, 2 minutes, 3 minutes, 5 minutes, or more. The duration of the stage 1110 may vary based on the starting temperature, with lower starting temperatures requiring relatively more time. If the preheating signal 1112 includes charge and discharge pulses of equal or nearly equal duration, the net charge of the battery 206 does not change substantially during this stage and remains at or near the initial SOC. Furthermore, the applied frequency regime of the pulse sequence is preferably chosen so as not to initiate electrochemical reactions or side reactions of the storage reaction. The preferred frequency range for the preheat pulse signal 1112 is 100hz to 100kHz.

[0160] The C-rate of the pulse applied during the preheat stage 1110 can vary widely and is determined primarily by the ohmic characteristics of the cell, the applied voltage, and the thermal behavior during this stage. C-rates of up to 30° C. or higher can be applied during stage 1110. Additionally, stage 1110 can be applied such that no net charging or discharging occurs, although in other embodiments the length of the charge pulse can be slightly longer (e.g., 1-15%) than the length of the discharge pulse to begin charging the cell at a relatively slower rate compared to subsequent stages. This can occur, for example, toward the transition from the preheat stage 1110 to the first charge stage 1120 as the battery 206 heats up toward a transition threshold temperature or time. Stage 1110 can thus be divided into a first sub-stage 1114, where no charging occurs, and a second subsequent sub-stage 1116, after reaching a higher temperature, where the charge pulse length is longer than the discharge pulse length to begin charging, but at a slower rate than the pulse charge second stage described below. An example embodiment of a preheat signal 1112 applied during both sub-phase 1114 and sub-phase 1116 is depicted in Figure 11E. The second sub-phase 1116 may introduce charge at a fixed rate (e.g., a 5% longer charge pulse) or may begin to gradually charge in constant increments for a duration (e.g., a 1% longer charge pulse for 30 seconds followed by a 2% longer charge pulse for 30 seconds, etc.) before transitioning to the first charge phase 1120.

[0161] The transition from phase 1110 to the first charging phase 1120, or alternatively, the transition from the first sub-phase 1114 to the second sub-phase 1116, may occur under conditions where pulse charging can occur at a high C rate for faster charging without causing significant side reactions such as lithium plating. In some embodiments, this condition occurs when the Warburg impedance (R Warburg ) does not result in a voltage that exceeds the overpotential range of either electrode. In other embodiments, the condition that can control the transition to pulse charging is R Warburgmay be when the activation impedance is reduced to 50% or less, 40% or less, 30% or less, 20% or less, or 10% or less of the total impedance of each electrode. In embodiments where the preheating stage 1110 transitions directly to the constant current charging stage 1130 (without the pulse charging stage 1120), the transition condition may in some examples be when the activation impedance drops to 50% or less, 40% or less, 30% or less, 20% or less, or 10% or less of the total impedance of each electrode.

[0162] In some embodiments, the preheat signal 1112 is applied while monitoring the temperature of the target source 206 and monitoring the temperature of the external ambient environment around the target source 206, e.g., the environment from which the target source 206 loses heat. The difference between the source temperature and the temperature of the ambient environment can be monitored and compared to a threshold absolute difference (e.g., 20 or 30 degrees Celsius), or alternatively, a gradient (e.g., a threshold rate at which the source temperature increases above the ambient temperature). This is to ensure that the temperature difference between the source and the ambient is not severe enough to cause damage to the source due to thermally induced mechanical stress. Depending on the particular implementation, if a threshold is approached, reached, or exceeded, the amplitude of the preheat signal can be reduced, or the gap time between adjacent charge and discharge pulse pairs can be increased, or a waiting period during which no signal is applied can be introduced. In some embodiments, the preheat phase 1110 can be performed while all external cooling devices (e.g., fans, liquid refrigerant circulation) are not operating simultaneously to minimize the temperature difference between the ambient and the source 206.

[0163] The first charging stage 1120 is a pulse charging stage in which a pulse charging signal is applied to the battery 206. Stage 1120 allows faster charging at high C-rates with reduced activation overvoltage and reduced occurrence of side reactions, as described in more detail herein. FIG. 11F is a current versus time graph depicting an exemplary embodiment of a pulse charging signal 1122 for use in stage 1120. The signal 1122 oscillates between zero and +Ipc, and in this embodiment is in the form of a square wave with the +Ipc pulse having a duration 1124 and a 50% duty cycle. During stage 1120, the magnitude of the signal 1122 can be controlled to maintain a constant temperature of the battery 206, or can be further increased to speed up the storage reaction to further reduce the overvoltage on the electrochemical interface. Current controlled pulses are described with respect to the preheat signal 1112 and the pulse charging signal 1122, but voltage controlled pulses can be used as well.

[0164] The pulse applied in step 1110 can have a voltage that exceeds the (upper and lower) cutoff voltage of the energy source 206. In some embodiments, the amount that the pulse in step 1110 can exceed the cutoff voltage is limited by the breakdown voltage of the electrolyte. The pulse applied in step 1120 can also have a voltage that exceeds the recommended (upper and lower) cutoff voltage of the energy source 206. In some embodiments, the amount that the pulse in step 1120 can exceed the cutoff voltage is less than or equal to the remaining impedance of the electrode multiplied by the pulse charging current (that portion of the impedance not avoided by the pulse charging, i.e., any remaining activation impedance plus the ohmic impedance).

[0165] The optimal frequency and duration 1124 of the applied pulses depends on the battery type. In many embodiments, the frequency (F pulse ) follows equation (8). (8)f pulse >1 / (R CT C DL )

[0166] f more than twice that of Eq. (8) pulse values ​​substantially eliminate activation impedance and activation overvoltage (e.g., R in FIG. 12D). CT and η* act components) and allows for faster charging without exceeding the maximum overvoltage at the EC interface. For a particular embodiment of a lithium ion battery with a graphite anode and nickel cobalt cathode chemistry, it has been found that a charge pulse duration 1124 of 2 milliseconds (ms) (e.g., 250 Hz at 50% duty cycle) can be utilized in the protocol 1100 to charge the battery 206 at a high rate (e.g., 0-75% charge in less than 15 minutes) without substantial capacity degradation over time (e.g., over multiple charge cycles in which the battery 206 is cycled from low or no charge to a nominal SOC level) compared to a constant current charge signal at a similar amperage. A charge pulse duration 1124 of 5 ms or less can charge the battery 206 at a high rate with significant improvement in capacity retention over time compared to a constant current charge signal at a similar amperage. The exemplary embodiments described herein can be applied at any charge pulse duration 1124 for which the battery type is operable. Embodiments include Li-ion battery charging pulse durations of 5 ms or less, 4 ms or less, 3 ms or less, 2 ms or less, and 1 ms or less. Durations may be as short as 0.05 ms, or 0.1 ms. Data was collected at a 50% duty cycle, but pulses can be applied at a variety of different duty cycles, such as 25-75%, 40-60%, and 45-55%. In an embodiment, pulses are applied at a pulse C-rate of 10.67C to charge 80% in 9 minutes, which results in a time-averaged C-rate of 5.33C for the second stage, given a 50% duty cycle (10.67C / 2).

[0167] Pulse charging can substantially increase the charging current because the voltage drop across the non-ohmic impedance is eliminated or minimized. In some embodiments, the non-ohmic Warburg impedance (R Warburg) and non-ohmic activation impedance (R CT ) is measured periodically and f pulse is chosen such that the sum of the Warburg impedance and the activation impedance exceeds a threshold percentage of the total impedance. For example, in pulse charging with twice the applied current as in constant current charging and a 50% duty cycle, the sum of the non-ohmic impedances avoided is preferably greater than 50% of the total impedance. Stated differently, the ohmic impedance is preferably less than 50% of the total impedance. The total impedance may be measured or may be based on preprogrammed estimates corresponding to various states of charge. The threshold percentage may be 50% of the total impedance, 60% of the total impedance, 70% of the total impedance, or others. Alternatively, f pulse can be selected such that the Warburg impedance exceeds a percentage of the total impedance (e.g., 60%, 50%, 40%, or 30%), and / or f pulse can be chosen such that the activation impedance exceeds a percentage of the total impedance (eg, 60%, 50%, 40%, or 30%).

[0168] Depending on the duty cycle, the time-averaged C-rate can be larger or smaller to meet the desired target (e.g., 80% SOC within about 9 minutes). The magnitude of the C-rate itself is not a constraint to the extent that the applied C-rate does not exceed the voltage and temperature constraints described herein, nor the chemical and physical constraints of the battery cells, nor the electrical and physical constraints of the system being charged and the charger. Thus, the time-averaged C-rate of the second phase can vary significantly depending on the embodiment. In one example, the time-averaged C-rate of the pulse charging phase 1120 is 4C-8C, although the present subject matter is not limited as such. For protocol 1100, time-averaged C-rates of 30C or greater are within the scope of the present subject matter.

[0169] The pulse signal 1122 may be applied at a current magnitude such that each battery cell exhibits a voltage response greater than the open circuit voltage of the cell, but less than the upper cutoff voltage of the electrochemical interface voltage on the anode and cathode electrodes (excluding ohms across voltage). In various embodiments, the pulses are applied such that each cell does not exceed the overvoltage range of the anode alone, the overvoltage range of the cathode alone, or the overvoltage range of the anode and cathode together. Pulse charging can drive cell voltages to higher voltages than constant current charging within the same (lower) temperature range as a result of the reduced activation overvoltage.

[0170] The optimal duration of stage 1120 depends on the battery type; longer pulse charging stages can be used for chemistries with more activation or activation that lasts at higher temperatures. Pulse charging stage 1120 can continue until the activation impedance is reduced to 50% or less of the full initial impedance (e.g., at the start of stage 1120). In other embodiments, stage 1120 can continue until the activation impedance is reduced to 40% or less, 30% or less, 20% or less, or 10% or less of the full impedance. Other constraints such as cell temperature and cutoff voltage can also determine when stage 1120 ends.

[0171] 11A and 11B, the first charging stage 1120 may continue for a predetermined period of time (e.g., time_1 to time_2) until a SOC or capacity threshold (e.g., SOC_1) is reached, a temperature threshold (e.g., temp_2) is reached, or any combination thereof (e.g., terminating when any of the time, SOC, or temperature thresholds are reached). Stage 1120 is intended for charging at a relatively low temperature where the advantages of pulsing dominate, but is not limited to such. For example, stage 1120 may also be designed to further increase the temperature to one suitable for transitioning to a second charging stage 1130 to apply a constant current charge to charge to a higher state of charge.

[0172] In the embodiment of FIG. 11B, stage 1120 ends when the temperature of battery 206 is about 50° C. In other embodiments, for example, the temperature threshold (temp_2) can be greater than 30° C., such as 30-60° C., or 40-55° C. Thresholds outside these ranges are possible based on the battery chemistry. In the embodiment of FIG. 11B, the temperature threshold that ends stage 1120 is reached when the battery SOC reaches about 55%. In embodiments using a SOC threshold, that threshold can be 30%-80%, 40%-70%, or 50-60%. In the embodiment of FIG. 11B, the second stage ends after a duration of about 5 minutes. In other embodiments, for example, the duration can be greater than 1 minute, such as 1-9 minutes, 2-8 minutes, 3-7 minutes, or 5-7 minutes.

[0173] The second charging stage 1130 is a constant current charging stage in which a constant current signal is applied to the battery 206 without pulsing. Stage 1130 is a constant current charging stage in which the activation and diffusion based impedance (e.g., R CT and R Warburg The present invention contemplates a relatively high temperature at the electrochemical interface where the charge current (component) is reduced, thus reducing the benefits of pulse charging. The reduced activation and diffusion impedance allows constant current charging at higher rates and higher SOC without exceeding the maximum overvoltage. Phase 1130 may begin after completion of the first charging phase 1120 and may continue until the battery 206 is fully charged or deeply charged (>50%). As the open circuit voltage of each cell rises, the magnitude of the charge pulse is preferably controlled so as not to exceed the upper cutoff voltage of each cell.

[0174] A constant current can be applied at a relatively high time-averaged C-rate, such as 4C to 8C (or higher). For a constant current, there is generally no difference between the time-averaged C-rate and the actual C-rate as the current is applied, but in some cases, small fluctuations in the current can make the time-averaged C-rate a more relevant metric.

[0175] In some embodiments, during the second charging phase 1130, the magnitude of the constant current charging signal may be varied as the charging process progresses. For example, in some embodiments, the magnitude of the constant current charging signal 1132 may begin phase 1130 at a relatively high C-rate to avoid exceeding the over-voltage range as the SOC increases, and then gradually transition to a lower C-rate value as the charging process progresses (see FIG. 12C). A relatively short pause or rest period may occur between constant current charges to allow the battery voltage to stabilize. FIG. 13A is a graph depicting exemplary levels of the constant current charging signal 1132 in stage 1130, where to complete protocol 1100, during a first sub-stage 1133, the signal 1132 is applied at a first C-rate (e.g., 6C-8C) for a first duration T1 (e.g., 60-120 seconds), followed by a relatively short pause period (e.g., 5-15 seconds) during which no signal is applied, and then during a second sub-stage 1134, the signal 1132 is applied at a second, relatively lower C-rate (e.g., 4C-6C) for a second duration T2 (e.g., 90-150 seconds). ), followed again by a relatively short pause period (e.g., 5-15 seconds) during which no signal is applied, then during a third sub-phase 1135, the signal 1132 is applied at a third, smaller C-rate (e.g., 2C-4C) for a third duration T3 (e.g., 90-150 seconds), followed again by a relatively short pause period (e.g., 5-15 seconds) during which no signal is applied, then during a fourth sub-phase 1136, the signal 1132 is applied at a fourth, smaller C-rate (e.g., 1C-2C) for a fourth duration T4 (e.g., 4-8 minutes). The durations T1-T4 during which the signal 1132 is applied during each sub-phase 1133-1136 may be constant or may be variable, where the signal 1132 is stopped when the battery (or cell) voltage reaches a selected threshold to avoid entering an over-voltage condition. The exemplary C rates and durations demonstrated herein are by way of example only and are not limiting as embodiments are practical outside these ranges. Stage 1130 can be performed at a single constant current rate, or in any number of two or more sub-stages (e.g., 1133-1136) in which the constant current rate is iteratively decreased.

[0176] Figure 13B is a graph of another exemplary embodiment of protocol 1100, where a second charging phase 1130 is applied with a constant current signal of gradually decreasing magnitude as described with respect to Figure 13A. Each of the sub-phases 1133-1136 may be terminated and transitioned to the next sub-phase upon the occurrence of a time threshold, a temperature threshold, a SOC threshold, a voltage threshold, and / or any combination thereof.

[0177] Protocol 1100 need not execute all three stages 1110, 1120, and 1130. In some embodiments, the first charging stage 1120 may be omitted and protocol 1100 may proceed immediately from pulse preheat stage 1110 to constant current charging stage 1130. In other embodiments, the second charging stage 1130 may be omitted and protocol 1100 may proceed immediately from pulse preheat stage 1110 to first charging stage 1120 and then terminate. In still other embodiments, pulse preheat stage 1110 may be omitted, for example, if battery 206 is already sufficiently heated. Exemplary embodiments having these and other variations to protocol 1100 are described with respect to FIGS. 19B-19G.

[0178] Protocol 1100 also includes monitoring each battery 206 for indications of a potential state of health. This monitoring may be performed during any and all of steps 1110, 1120, and 1130 and may include voltage and / or impedance response analysis and / or monitoring for indications of the occurrence of lithium coating. For example, the voltage and impedance of each battery 206 may be monitored with voltage and impedance response analysis to detect indications of accelerated or decelerated side reactions (see, e.g., FIG. 12E). Detection of a side reaction may be used to modify characteristics of the charging signal, e.g., the voltage of the charging signal may be reduced to slow down the side reaction, the duration of the charging pulse may be reduced to slow down the side reaction, and the frequency of application of the charging pulse may be reduced to slow down the side reaction, or vice versa if the rate of the side reaction is determined to be low enough to allow faster charging. Voltage and impedance analysis may be performed during all three phases (1110, 1120, 1130), only during the preheat phase 1110, only during the first charging phase 1120, only during the second charging phase 1130, or any combination thereof.

[0179] 14 is a series of plots depicting an example embodiment 1400 of monitoring for the occurrence of lithium coating. In this embodiment, a signal 1402 is applied to the battery 206, which includes a charge pulse immediately followed by a discharge pulse of equal or nearly equal duration, as shown in the top plot 1401. There may be a small time gap between the application of the pulses. Here, a first charge pulse 1404 and a subsequent discharge pulse 1405 are shown for an example 1408 where lithium coating has not occurred, and a second charge pulse 1406 and a second discharge pulse 1407 are shown for an example 1409 where lithium coating has occurred.

[0180] The voltage response of the battery 206 to the signal 1402 may be monitored as shown in the middle plot 1410. For an example where lithium coating has not occurred, a normal voltage response 1412 is shown on the left, and a voltage response 1414 indicating that lithium coating has occurred, specifically, that the coated lithium has been stripped, is shown on the right. If a lithium coating event has occurred, this will be evident in the portion of the voltage response 1414 to the discharge pulse 1406, typically the relatively rapid transition of the response 1414 from one voltage to another while the discharge pulse is applied at a generally constant magnitude. Such a rapid transition of the voltage response 1414 indicates that the coated lithium is then stripped. Thus, the response is produced by lithium stripping, and thus indicates that lithium coating has occurred prior to the application of the discharge pulse 1407.

[0181] Coverage can be detected directly from the voltage response, as depicted in the bottom plot 1420, or from a derivation of the voltage response 1422. The derivation of the voltage response produces transitions (e.g., either positive or negative peaks or spikes) when the voltage response undergoes relatively significant non-linear transitions, such as when the current pulse is initiated and terminated 1424, and when a lithium stripping event occurs as shown by 1426. In some embodiments, only the voltage response or derivation to the discharge pulse is monitored. If lithium cover is detected, the characteristics of the charging signal can be modified as described with respect to impedance monitoring above. The lithium cover detection 1400 can be performed intermittently during all three phases, only during the preheat phase 1110, only during the first charging phase 1120, only during the second charging phase 1130, or any combination thereof. For example, the monitoring routine 1400 can be performed once every 5 seconds, 10 seconds, 20 seconds, or any other desired interval. Routine 1400 may include application of one pulse pair (e.g., 1404 and 1405) or multiple pairs. Pulse lengths may range from 0.1 ms to 10 seconds, and are preferably no longer than 100 ms, to have minimal impact on the charge time of routine 1400.

[0182] FIG. 15A is a plot of experimental data comparing the effects of pulse charging and constant current charging on a pair of lithium ion battery cells rated for use in power applications such as conventional EV car battery packs. Data 1502 shows results from a cell charged constant current at a 1C rate, and data 1504 shows results from a cell pulse charged in a manner similar to that described for the pulse charging phase 1120. FIG. 15A compares capacity in milliamp hours (mAh) with cycle time, which is a measure of the cumulative time the cell was tested in repeated cycles. Constant current charging cycles were formed by a 1C constant current charge to approximately 2.5Ah of the 2.95Ah maximum rated capacity, followed by a discharge to zero at a 1C rate, then the cycle was repeated. Pulse cycles were formed by applying a 1C pulse of 2ms duration with a 50% duty cycle for 1 hour, followed by a discharge at a 1C rate for 1 hour, then the cycle was repeated. The experimental data was collected at 25° C., and the cycles were performed for approximately 280 hours. FIG. 15A shows that in each cycle, the pulse-charged cell achieved, on average, 10% more capacity than the constant-current charged cell, and the cycle lives of both deteriorated at approximately the same rate.

[0183] FIG. 15B shows the same data as FIG. 15A but in normalized form, with capacity shown as a percentage of the initial capacity achieved. This again shows roughly the same shortening of cycle life for the pulse charged cell data 1514 compared to the constant current data 1512. Thus, the data in FIGS. 15A-15B show that pulse charging has not caused a degradation of extended cycle life compared to the constant current cell. Pulse charging can reduce activation impedance and result in improved capacity. Adjusting the conditions to pulse charge the cell to the same lower capacity that the constant current cell was achieving would result in improved cycle life for the pulse charged cell compared to the constant current charged cell.

[0184] FIG. 16A is a plot of experimental data comparing the effect of charging protocol 1100 to constant current charging on a pair of lithium ion battery cells rated for use in power applications such as conventional EV car battery packs. Protocol 1100 was performed with a preheat phase 1110, a first pulse charge phase 1120, and a second charge phase 1130, then cooled and discharged to form one cycle. This cycle was repeated consecutively and independently on the two battery cells. FIG. 16C is a graph of capacity versus time, and FIG. 16D is a graph of voltage versus time, both showing data collected from the execution of one exemplary cycle of protocol 1100 on the battery cells. This exemplary embodiment of protocol 1100 included a net zero charge pulse preheat phase 1110 that raised the cell temperature to about 20° C. to about 35° C. This was followed by a 3 minute pulse charge phase 1120 in which 2 ms pulses were applied at 5C and 50% duty cycle. This was followed by a constant current charging phase 1130 having a first sub-phase 1133 with a 7C rate for 90 seconds followed by a rest period of 10 seconds, a second sub-phase 1134 with a 5C rate for 120 seconds followed by a rest period of 10 seconds, a third sub-phase 1135 with a 3.3C rate for 120 seconds followed by a rest period of 10 seconds, and a fourth sub-phase 1136 with a 1.8C rate for 6 minutes. The pulse charging phase 1120 and sub-phases 1133-1136 are also subject to cell voltage limits (4.25V for phase 1120 and 4.2V for sub-phases 1133-1136). This example of protocol 1100 achieved over 75% nominal capacity in under 13 minutes. After charging, a relatively long rest period of approximately 60 seconds was performed to allow the battery cell to cool, after which the cell was discharged at a rate that achieved zero capacity one hour after the start of protocol 1100.

[0185] Referring back to FIG. 16A, data 1602 shows results from a cell charged galvanically at a 3.2C rate, and data 1604 shows results from a cell charged with protocol 1100, as described with respect to FIGS. 16B-16C. FIG. 16A compares capacity (mAh) with cycle time, a measure of the cumulative time the cell was tested in repeated cycles. The galvanostatic charge cycle of data 1602 was formed by applying a constant current of 3.2C for 13 minutes, followed by discharge at a rate that achieved full discharge 1 hour after initiation, resulting in a full galvanostatic cycle lasting 1 hour, and then the cycle was repeated continuously. The cycle was performed for approximately 200 hours. FIG. 16B shows the same data as FIG. 16A, but in normalized form, with capacity shown as a percentage of the initial capacity achieved.

[0186] 16A-16B show that standard constant current fast charging data 1602 exhibits rapid capacity fade. Such rapid capacity fade is caused by high impedance growth induced in the cell by constant current charging. Conversely, charging protocol 1100 avoids such impedance growth and allows for significantly improved capacity retention (similar to the 1C reference rate of FIGS. 15A-15B) while achieving 75% of nominal capacity in under 13 minutes. Still further refinement of the parameters of protocol 1100 can result in even faster charging times of 10 minutes or less to reach the same or similar capacity.

[0187] The battery cells used to collect the data in Figures 15A-15B were subjected to a slow charge cycle characterization analysis, and the results are presented in the voltage vs. capacity plots of Figures 17A-17B. Figure 17A plots data for a 1C constant current charged cell, where characterization curve 1702 was taken at the beginning of life (BOL) before the testing described with respect to Figures 15A-15B, and then characterization curve 1704 was taken at the end of life (EOL) after the testing was completed. Comparison of curves 1702 and 1704 shows that the constant current cell underwent an irreversible capacity loss of about 15%. Figure 17B plots data for a 1C pulse charged cell, where characterization curve 1712 was taken at the beginning of life (BOL) before the testing described with respect to Figures 15A-15B, and then characterization curve 1714 was taken at the end of life (EOL) after the testing was completed. Comparison of curves 1712 and 1714 shows that the pulse charged cell also underwent 15% irreversible capacity loss. Thus, at EOL, the pulse charged cell had similar irreversible capacity loss as the constant current cell compared to (BOL). Cycle life was also comparable. Thus, pulse charging does not significantly degrade the cell or cause rapid impedance growth.

[0188] 18A is a plot of the imaginary and real impedance components of a constant current charged cell and a pulse charged cell at EOL. Data 1802 corresponds to the constant current charged cell and data 1804 corresponds to the pulse charged cell. Both cell pairs show substantially the same impedance characteristics, with the pulse charged cell showing only slightly higher ohmic and activation components to their impedance. This is likely due to the build-up of the SEI layer and the resulting impedance growth due to higher than optimal temperatures, which may be mitigated by further refinement of the parameters of protocol 1100 to allow for better temperature control.

[0189] FIG. 18B is a plot of cell voltage versus time depicting experimental data collected for a lithium-ion cell subjected to constant current charging (1812), pulse charging with a pulse duration of 10 ms (1814), and pulse charging with a pulse duration of 2 ms (1816). Charging with either constant current or pulse charging, followed by a rest, allows for rapid measurement of ohmic / activation versus diffusion contributions. The measurements are summarized in Table 1 below. These findings indicate that pulse charging 1816 reduces the activation impedance and activation overpotential while maintaining a similar diffusion overpotential. [Table 1]

[0190] 19A-G are block diagrams depicting an exemplary embodiment of the implementation of a charging protocol 1100 for various battery types. In these figures, the cell temperature generally increases over time. FIG. 19A depicts protocol 1100-1 implemented according to the embodiment of FIGS. 11A-11B, in which a pulse preheat phase 1110 is first performed, followed by a pulse charging phase 1120, and ending with a relatively high temperature constant current (CC) charging phase 1130. Protocol 1100-1 can be used, for example, with NMC or NCA battery cells.

[0191] 19B depicts protocol 1100-2 in which constant current charging phase 1130 is omitted and has a pulse preheat phase 1110 performed first, followed by a pulse charging phase 1120. By way of example, this embodiment may be suitable for battery types having chemistries that have relatively high activation but relatively low diffusion at acceptable charging temperatures, as compared to NMC or NCA battery cells.

[0192] 19C depicts protocol 1100-3 in which the preheat stage 1110 and the constant current charging stage 1130 are omitted, and only the pulse charging stage 1120 is included. By way of example, this embodiment may be suitable for battery types having chemistries that have relatively high activation at acceptable charging temperatures compared to NMC or NCA battery cells.

[0193] 19D depicts protocol 1100-4 in which the preheat stage 1110 is omitted and has a pulse charging stage 1120 followed by a constant current charging stage 1130. As an example, this embodiment may be suitable for battery types having a chemistry that has relatively low activation at high states of charge compared to NMC or NCA battery cells, allowing constant current charging at high states of charge.

[0194] 19E depicts protocol 1100-5, which has a pulse preheat phase 1110 immediately followed by a constant current charging phase 1130. The pulse charging phase 1120 has been omitted. By way of example, this embodiment may be suitable for battery types having chemistries that have relatively low activation at acceptable charging temperatures compared to NMC or NCA battery cells.

[0195] 19F depicts protocol 1100-6, which is similar to 1100-5 with a first preheat phase 1110-1 and a constant current phase 1130-1, but repeats this regime with a second pulse preheat phase 1110-2 and a second constant current charging phase 1130-2. By way of example, this embodiment may be suitable for battery types that have a chemistry that has relatively low activation at acceptable charging temperatures compared to NMC or NCA battery cells, and that are run over two distinct temperature regimes.

[0196] 19G depicts protocol 1100-7 having a pulse preheat phase 1110 immediately followed by a first constant current charging phase 1130-1, then followed by a pulse charging phase 1120 and a second constant current charging phase 1130-2. By way of example, this embodiment may be suitable for battery types having chemistries that have relatively high activation at moderate states of charge compared to NMC or NCA battery cells.

[0197] The protocol embodiments described with respect to Figures 19A-19G, and elsewhere herein, may be executed independently for each energy source in the system being charged. Information regarding the state of each source (e.g., SOC, temperature, voltage response, impedance response, indication of lithium coverage, etc.) may be collected for each source and communicated to a control system (e.g., 102) to enable coordinated system-wide management of application of protocol 1100 and allocation of power at the power connections (e.g., 110) to each module or source. For example, a modular energy system 100 having an array of N different modules 108, each having an energy source 206, may execute protocol 1100-1 of Figure 19A independently in each of the N modules 108. A determination of when a transition condition (e.g., from stage 1110, 1120 to stage 1120, 1130, or between sub-stages 1114, 1116, 1133-1136) has been reached for each source 206 can be made by the control system 102 (e.g., MCD 112) and appropriate instructions can be issued to each source 206 in that module 108 to transition to the next stage (e.g., by MCD 112 instructing LCD 114 to modify the switching signal to converter 202 to generate a charging pulse (or constant current) as opposed to a preheat pulse train). A first group of one or more modules 108 may meet the condition to transition from the pulse preheat stage 1110 to the pulse charging stage 1120 (e.g., at a minimum temperature, etc.), while a second group of one or more different modules 108 may not yet meet the condition. Thus, the system 100 can control and partition the application of the power source using the control system 102 (e.g., at the direction of the MCD 112) such that a first group of one or more modules 108 is in the pulse charge phase 1120 while a second group of one or more different modules 108 remains in the pulse pre-heat phase 1110. Once each module 108 in the second group independently reaches a transition condition, that module 108 can enter the pulse pre-heat phase along with the first group of modules 108.Similarly, each module 108 in the pulse charging stage 1120 may transition from stage 1120 to stage 1130 as the module 108 independently reaches the conditions for transitioning to the constant current charging stage 1130. In some examples, the different stages 1110, 1120, and 1130 may all be executed simultaneously for different energy sources in the same system. The same is true for the execution of the protocol sub-stages (e.g., 1114, 1116, and 1133-1136) for sources in the system, where different sub-stages may be executed simultaneously for different sources.

[0198] Exemplary System Configurations for Charging and Heating Embodiments 20A-20F are block diagrams depicting exemplary embodiments of a system to which the embodiments described hereinbefore and hereinafter may be applied. Although the examples are described in the context of a mobile application, i.e., charging an EV, the examples may be implemented in stationary applications (e.g., charging an energy buffer) and portable power applications (e.g., charging a power tool battery) as well as those described herein.

[0199] In the example system configuration 2010 of FIG. 20A, charging source 150-1 includes a DC charging source 2002 that outputs a DC charging voltage or current to a switch circuit 2004 (e.g., an H-bridge), which can output a positive, negative, or zero DC charging voltage or current for use in pulse heating and / or charging. The pulse train is provided through terminals (or nodes) 2015-1 and 2015-2 to an EV 2006-1 with an electric powertrain 2012 that includes N series-connected batteries 206-1 through 206-N in a conventional non-switchable configuration. Once charged, powertrain 2012-1 can supply DC power to an inverter 2111, which converts the DC power to three-phase power that is then output to the EV motor 2112.

[0200] 20B is similar to configuration 2010, except that switch circuit 2004 is contained within EV 2006-2. DC power from charging source 150-2 is received by EV 2006-2 and pulsed by circuit 2004 under control of EV 2006-2 to provide a pulse train for charging or heating sources 206-1 through 206-N.

[0201] In the example configuration 2030 of Figure 20C, charging source 150-3 is configured according to the embodiment of system 100 described with respect to Figures 1A-10F. Charging source 150-3 receives AC power from grid 2008 and provides it as a single-phase pulse train to electric powertrain 2012-1 of EV 2006-1.

[0202] In the example configuration 2040 of FIG. 20D, DC charging source 150-2 supplies DC power to EV 2006-4 having electric powertrain 2012-2 configured according to the embodiment of system 100 described with respect to FIGS. 1A-10F. In this example, powertrain 2012-2 has three arrays of modules 108-1-108-N configured to generate three-phase signals PA, PB, and PC. EV 2006-4 includes routing circuitry 2110 that reroutes the DC power from two lines to three lines to charge the three arrays (e.g., PA and PB, PB and PC, PA and PC). The operation of the routing circuitry is described in U.S. Patent Publication No. 2021 / 0316621A1, entitled SYSTEMS, DEVICES, AND METHODS FOR MODULE-BASED CASCADED ENERGY SYSTEMS, and co-pending U.S. Patent Application No. 17 / 574,508, both of which are incorporated by reference in their entirety for all purposes. Other configurations may also be used to route DC power to each array for charging. Each module 108 may then operate its converter 202, independent of the others, to apply DC power to its energy source 206 in a pulsed manner for heating and / or charging (e.g., under regulation of the MCD 112). Once charged, the powertrain 2012-2 may provide three-phase power to the motor 2012.

[0203] In the example configuration 2050 of FIG. 20E, the charging source 150-4 is an AC charging source and supplies three-phase AC power. The pulse train is provided through terminals (or nodes) 2015-1, 2015-2, and 2015-3 to an EV 2006-4 having an electric powertrain 2012-2 like that of configuration 2040. Because the three-phase power is provided directly to the powertrain 2012-2, the routing circuit 2110 can be omitted. Then, similar to configuration 2040, each module 108 can operate its converter 202 independently of the others to apply DC power to its energy source 206 in a pulsed manner for heating and / or charging (e.g., under regulation of the MCD 112). Once charged, the powertrain 2012-2 can supply the three-phase power to the motor 2012.

[0204] In the example configuration 2060 of FIG. 20F, charging source 150-3 is similar to that of configuration 2030, except that it is configured to directly supply three-phase power to EV 2006-5, which is similar to that of configuration 2050. Here, because both charging source 150-3 and powertrain 2012-2 include energy storage systems 100, either charging source 150-3 or powertrain 2012-2 can be responsible for creating the pulse trains used to charge each energy source. Performing the pulse function in powertrain 2012-2, a particular converter 202 in each of its modules 108, is advantageous in that it allows the pulse trains of each energy source to be created and applied independently, thus providing charging and / or heating functions customized for the particular source.

[0205] Without being limited as such, configurations 2010, 2020, and 2030 may be particularly suitable for relatively low voltage applications (e.g., 10 watt-hours to 20 kilowatt-hours (kWh)), configurations 2040 and 2050 may be particularly suitable for relatively high (medium) voltage applications (e.g., 20 kWh to 100 kWh), and configuration 2060 may be particularly suitable for relatively high voltage applications (e.g., 100 kWh or greater).

[0206] The embodiments described herein may also be used to charge an EV powertrain with energy created from the EV's regenerative braking system. For example, during braking, the generated power may be applied to the powertrain as a pulse train, either by switching a circuit electrically located between the regenerative braking system and the electric powertrain (e.g., in the case of a conventional non-switchable series-connected battery pack) or using a converter 202 integrated within module 108, as in the case of cascaded converter system 100. Management of the switching to generate the appropriate pulse train may be under the control of a control system of the EV, such as control system 102 (e.g., MCD 112).

[0207] Exemplary Charging and Heating Embodiments Based on Impedance, Inductance, and / or Thermal Property Information The following exemplary embodiments describe execution of the pre-heating stage 1110 and / or pulse charging stage 1120 of the protocol 1100 based on evaluated impedance and / or inductance information of one or more target energy sources 206. Additionally or alternatively, the pre-heating stage 1110 may be executed based on evaluated thermal characteristics, such as thermal impedance and / or thermal capacitance, of one or more target energy sources 206. These embodiments may be executed by or under the direction of a controller 2101, which may include processing circuitry and memory, and may be configured as a single device or multiple devices. The controller 2101 may be associated with any of the systems described herein, including systems based on the modular cascaded system 100, such as the various configurations 2010-2060 described with respect to FIGS. 20A-20F, and systems that are not. The controller 2101 may be located exclusively within one device or system, such as within a device charger, a charging source 150, or within an energy storage system or EV. Controller 2101 may alternatively be distributed across multiple devices or systems, relying, for example, on coordination between separate control devices within both charging source 150 and the EV. Controller 2101 may be or include control system 102 in embodiments where charging is controlled at least in part by system 100.

[0208] FIG. 21A is a flow diagram depicting an example embodiment of a method 2100 for performing at least one of steps 1110 and 1120 based on evaluated impedance and / or inductance information. In step 2102, the controller 2101 evaluates the charge level (e.g., SOC) of one or more sources 206 ("target sources 206") being subjected to the protocol 1100. The charge level may be used to determine the amount of charge to be applied throughout the protocol 1100 and may be repeated as necessary during any step of the protocol 1100. An increase in the charge level may be used to reduce the available overvoltage for both the anode and cathode and thus reduce the applied current as the charge level increases. The frequency response of the target source 206 also depends on the charge level and thus the f preheat and f pulse The charge level of the target source 206 may be determined according to techniques known to those skilled in the art.

[0209] In step 2104, the controller 2101 may evaluate one or more impedances of the target source 206, including total impedance, ohmic impedance, and / or activation impedance. Impedance may generally be measured in any manner known to those skilled in the art using one or more stimulation signals. In some examples, impedance is measured by electrochemical impedance spectroscopy (EIS) using a voltage or current frequency stimulation pulse generator, data acquisition circuitry, and impedance estimation processing circuitry included in the controller 2101. Total impedance, as well as activation and ohmic impedance, may also be measured in response to the application of a stimulation signal (e.g., a current pulse) and the ohmic impedance (R ohmic ) and activation impedance (R CT +R Warburg ) and the total voltage drop and voltage drop component η* ohmic and η* actThe current response can also be measured by measuring the resulting voltage response, including (see FIG. 12F). This can alternatively be performed using application of a voltage pulse and evaluation of the current response.

[0210] In step 2106, the controller 2101 can evaluate the inductance of the charging path between the charging source and the target source 206. As with impedance, the inductance can be measured in any manner known to one of skill in the art. In some examples, the inductance is measured by electrochemical impedance spectroscopy (EIS) using a voltage or current frequency sweep pulse generator, response data acquisition circuitry, and inductance estimation processing circuitry included in the controller 2101. The total inductance can also be measured by applying a current pulse and measuring the resulting voltage response, or alternatively, with the application of a voltage pulse and evaluation of the current response. The inductance can be measured at the terminals (e.g., the first node and the second node) where the charging signal is output from the charging source 150 to the system including the target source 206.

[0211] In step 2108, the controller 2101 may evaluate one or more thermal aspects of the target source 206. This may include measuring the temperature of the target source 206, such as by using a temperature sensing device on, in, or in proximity to the target source 206. This measured temperature may indicate an internal temperature of the target source 206. An external or ambient temperature may also or alternatively be measured, which indicates the temperature of the environmental conditions of the controller 2101. Additionally, the thermal resistance and / or thermal capacitance of the target source 206 may be measured. The thermal resistance may be measured by applying one or more preheat pulses to the target source 206 to generate a certain amount of localized heating and then measuring the temperature response of the target source 206. Based on the temperature rise response and the rise time constant, the capacitance may be estimated. The thermal resistivity may be determined based on a thermal circuit model or a thermal finite element simulation-based model, as known in the art.

[0212] Steps 2102-2108 may be performed in any desired order and are not limited to the sequence shown in FIG. 21A. Additionally, in some embodiments, controller 2101 may not need to evaluate all of the information described in steps 2104-2108, and thus may omit any one, two, or all three of these steps, as any aspect of the information collected at a particular step may be. For example, the inductance of the charging path in system 2101 is known, and in the implementation described, controller 2101 does not need to perform step 2106. Similarly, in embodiments that do not perform preheat phase 1110, evaluation of thermal resistance and / or capacitance in step 2108 may be omitted, and in some cases, step 2108 may be omitted entirely. These examples are not exhaustive, and further variations exist.

[0213] In some embodiments, one or more of the impedance, inductance, thermal resistance, and thermal capacitance of the target source 206 may be characterized during development or after manufacture, and those characterized parameters may be utilized in selecting and programming appropriate frequencies, currents (e.g., C-rates), current limits, temperature limits, voltages, and / or voltage limits (as applicable) for the preheat phase 1110, the pulse charging phase 1120, and / or the charging phase 1130. In such embodiments, evaluation of those parameters in one or more of steps 2104-2108 may be omitted.

[0214] In some embodiments, the controller 2101 may be configured to recognize the target source 206 as a model type, product class, or chemistry based on the identifier (e.g., a bit string) and reference a data structure (e.g., a data array or lookup table) containing associated characteristics (e.g., impedance, inductance, thermal characteristics) for the target source 206 based on the model type or class, thereby avoiding the need to perform an in field evaluation of those parameters, as in steps 2104-2108. In some cases, the data structure may include parameters for the execution of the protocol 1100 (e.g., frequency of the heating signal, frequency of the pulse charging signal, current (e.g., C-rate), current limits, temperature limits, voltage, and / or voltage limits for the preheat phase 1110, the pulse charging phase 1120, and / or the charging phase 1130 (as applicable)). Recognition of the model type, class, or chemistry may be performed by reading the identifier or other indicia from a local memory associated with the source 206, such as a battery management system, or by retrieval from a cloud-based server (via a wired or wireless internet connection). Alternatively, the source 206 may have an identifier tag antenna that can be read by a local reader of the controller 2101, such as using near field communication (NFC) or RFID. In another example, the type, class, or chemistry may be manually uploaded or entered into the controller 2101.

[0215] Instead of relying on model type or class, a target source may be characterized prior to deployment in the field, such as during a pre-commercial manufacturing or testing process, and the characterized information (e.g., impedance, inductance, thermal properties) may be digitally stored and associated with the target source 206, such as in a local memory of a battery management system associated with the target source 206 or in a server located in a cloud network. The characterized information may be retrieved locally from the local memory (e.g., via a communications bus) or from a cloud-based server (e.g., via a wireless or wired internet connection) and utilized to determine appropriate parameters for execution of protocol 1100 (e.g., frequency, current (e.g., C-rate), current limits, temperature limits, voltage, and / or voltage limits for preheat phase 1110, pulse charging phase 1120, and / or charging phase 1130 (as applicable)). Retrieval from the cloud-based server can include the controller 2101 reading or receiving one or more serial numbers or other unique identifiers (or data location identifiers) of the target sources 206 and communicating that identification information to the cloud-based server, which can respond with the characterized information and / or protocol execution parameters. In lieu of or in addition to communicating the characterized parameters, protocol execution parameters (e.g., frequency, current (e.g., C-rate), current limits, temperature limits, voltage, and / or voltage limits for the preheat phase 1110, pulse charging phase 1120, and / or charging phase 1130 (as applicable)) can be communicated to the controller 2101 via either a local communications connection or a wireless or wired internet connection.

[0216] In step 2110, the controller 2101 may perform a verification or validation to determine whether the target source 206 is in a suitable state for execution of the protocol 1100. Any one or more of the evaluated parameters (total impedance, activation impedance, ohmic impedance, inductance, source temperature, external temperature, thermal resistance, thermal capacitance) may be compared to a verification condition, such as a minimum and / or maximum limit of the allowable value of the parameter (e.g., a threshold range). For example, it may be determined whether the activation impedance is within a threshold range of an acceptable or tolerable activation impedance, and if so, the condition may be determined to be met and the controller 2101 may proceed to evaluate the next parameter. This process may continue until all parameters are verified. If any one or more parameters violate the verification condition, the controller 2101 may decide not to execute the corresponding stage of the protocol 1100. For example, if the thermal resistance is too high, the controller 2101 may decide not to perform the pre-heating stage 1110, or if the activation impedance is too high, the controller 2101 may decide not to perform the pulse charging stage 1120 and instead proceed with constant current charging at a relatively low current.

[0217] In step 2112, the controller 2101 can then select protocol settings (e.g., values, ranges, or limits) for execution of the protocol 1100 based on the evaluated parameters. preheat The value or range (upper and lower limits) of the tolerance for f pulse, current amplitudes for application in the positive and negative preheat pulses 1112, currents for application in the charge pulses 1122, voltages for application in the positive and negative preheat pulses 1112, voltage amplitudes for application in the charge pulses 1122, and / or duty cycles of the preheat signal 1112 or the pulse signal 1122. The protocol settings may also include tolerances or ranges for monitored responses from the source 206 during execution of the protocol 1100, such as acceptable voltage levels in the voltage response 1212 (e.g., peak total voltage, anodic overvoltage, cathodic overvoltage), acceptable impedances (e.g., total impedance, activation impedance, ohmic impedance), maximum source temperature, maximum rate of rise of source temperature, and acceptable concentration gradients (e.g., concentration overvoltage). Each step 1110, 1120, and 1130 of protocol 1100 may have multiple different values ​​or ranges for a particular setting, and these values ​​or ranges may be cycled through as controller 2101 progresses through a particular step (e.g., repeatedly increasing or decreasing the applied current in pulse 1122 as controller 2101 progresses through step 1120).

[0218] In one embodiment, the controller 2101 causes an evaluation of the impedance of the target source 206 before or during the pre-heating phase 1110, which is then used to determine the voltage or current amplitude of the heating signal 1112. If the evaluated impedance is greater than an impedance threshold, a relatively low amplitude can be selected, or if the pre-heating phase 1110 has already started, the amplitude of the heating signal can be reduced to slow down the heating rate. If the evaluated impedance is less than an impedance threshold, a relatively high amplitude can be selected, or if the pre-heating phase 1110 has already started, the amplitude of the heating signal can be increased to accelerate heating.

[0219] In step 2114, the controller 2101 can use the selected protocol settings to perform one or more verified stages 1110, 1120, 1130 of the protocol 1100. Each stage of the protocol 1100 can be run in its entirety with these settings, or the settings can be periodically adjusted, such as adjusting to increase SOC, as the stage progresses. The controller 2101 can periodically perform evaluation steps 2102, 2104, 2106, and / or 2108 throughout each stage of the protocol 1100. The evaluated parameters can be used to repeat the verification step 2110 and / or review the protocol settings. For example, while applying the preheat pulse train 1112, the controller 2101 can periodically cause application of a current pulse 1214 and direct measurement of a voltage response 1212 to evaluate balanced activation and ohmic overpotentials (or impedances), evaluate whether pulse charging is suitable, and / or update stored values ​​for activation and / or ohmic impedance. Also, while applying the charge pulse 1122, the controller 2101 periodically causes the application of a current pulse 1214 (of the same or similar amperage) and directs the measurement of a voltage response 1212 to determine the activation voltage drop (η* act ) and ohmic voltage drop (η* ohmic ) can be evaluated. The controller 2101 can then adjust the amplitude and / or frequency of the applied current or voltage signal based on the evaluated feedback at the particular stage. The method 2100 can continue until the target source 206 is adequately heated and / or charged.

[0220] Exemplary embodiments of charging with detection of voltage shift due to concentration change The embodiments described herein can be implemented to charge the source of interest 206 while accounting for voltage shifts due to concentration changes. These voltage shifts are due to an increase in open circuit cell voltage due to lower concentrations on the electrodes (e.g., Nernst overpotential) and an increase in reaction rate loss due to lower concentrations at the interfaces (e.g., activation overpotential). Relief of the Nernst overpotential requires back diffusion toward equilibrium and typically takes much longer than relieving the activation overpotential. Figure 22 shows the relationship between the equilibrium state (C R = 1, solid line) and after diffusion-induced concentration changes (e.g., C R FIG. 1 illustrates an exemplary voltage vs. current curve for a lithium-ion cell with a charge-discharge current (Vc=0.1, dashed line). When in equilibrium, the cell has an open circuit voltage E 0 Nernst To drive the high charging current i_cell, E 0 Nernst The voltage at which the equilibrium activation overvoltage (η 0 act If the total applied voltage is too large, the acceptable anode overpotential range will be exceeded and lithium coating may occur. After the concentration change, the open circuit voltage is E* Nernst and to drive the same current i_cell, the applied voltage is η* conc must be increased, which corresponds to the degree to which the cell is de-balanced.

[0221] Nernst overpotential due to concentration shift (η conc-Nernst ) can be derived from the Nernst equation for a single reactant species (neglecting product accumulation) and is given by (9), where R is the Universal Gas Constant (8.314 JK -1 Mol -1 ), T is the temperature in Kelvin scale, n is the amount of electrons involved in the electrochemical reaction (e.g., the lithium main reaction is a simple one-electron transfer reaction), and F is the Faraday constant (coulombs per mole of electrons, 96485.33 C mol -1 ) and

number

number

[0222] η conc If E is known, it can be used to demonstrate that the application of overvoltage during pulse charging does not exceed the acceptable anode and cathode overvoltage ranges. 0 Nernst and η 0 act The value of may be determined by characterization (as described below) or may be estimated during pre-distribution manufacturing or testing (modeled through software) or in the field (e.g., measured while in use in an EV) based on standard values ​​for the source type or class. The value may then be stored or programmed into the controller 2101.

[0223] η* act The value of is determined, for example, by evaluating the value of the voltage response 1212 after T_fall and η* ohmic and subtracting the estimated value of η from the voltage response 1212 (see FIG. 12F). 0 ohmic Since the change in is small, you can use η 0ohmic =η* ohmic or alternatively, η* ohmic η 0 ohmic can be estimated to be slightly higher than η, for example, 5-10% higher. Alternatively, η* ohmic can be determined by measuring the voltage response 1212 after a very short period of time (e.g., less than 1 or 2 ms), or by monitoring the voltage response 1212 over T_fall and determining η* during T_fall. ohmic From η* act η* is determined based on the variation in the voltage decrease rate that indicates the transition to act It can be measured directly by assessing the size of the portion only.

[0224] It is possible, but E* Nernst Measurement of the value of η is difficult to perform during the charging phase due to the relatively long duration involved. conc-activation can be determined, (1 / α) and η conc-Nernst Since it is equivalent to the product of , we can use our estimate of α to get η conc-Nernst Furthermore, the value of c 0 is typically known (e.g., 1.0 to 1.5 mol for a lithium-ion battery), allowing the concentration gradient (c 0 / c*), which allows for adjustment of the charging process based on concentration gradients, if desired.

[0225] The equilibrium impedance data structure (e.g., a data array or look-up table) is used to calculate the R at equilibrium as a function of SOC (e.g., 0 to 90%) and temperature (e.g., -20 to 50°C). 0 ohmic and R 0 CT A visual representation of an exemplary lookup table is shown below in Table 2. Each cross-referenced grid location (x1 to x80) contains the R 0 ohmic and / or R 0CT Here, SOC and temperature are described in increments of 10, however, in other embodiments, finer (or coarser) increments of SOC and temperature may be used to provide a desired level of granularity for implementation. 0 ohmic and R 0 CT The value of R is determined using a current pulse and voltage response technique (the measured magnitude of the applied current and voltage response during T_rise). 0 ohmic and R 0 CT can be calculated, see FIG. 12F) or by using impedance response techniques (R 0 ohmic and R 0 CT can be determined by characterizing the source of interest (or a representative source) using a vector (which can be extrapolated from the x-axis as shown, see FIG. 12E). [Table 2]

[0226] η 0 ohmic The value of R at the current (or most recent) values ​​of SOC and temperature of the target source 206 0 ohmic can be calculated by selecting a value of and multiplying it by the current of the applied pulse 1214, which can be varied (η 0 ohmic =I pulse R 0 ohmic (SOC,T)). The amperage of the applied current pulse 1214 can be the same as or similar to the amperage of the charging current used during the respective phase (e.g., pulse 1122). Similarly, η 0 act The value of R at the current (or most recent) values ​​of SOC and temperature of the target source 206 0 act and multiplying it by the current of the applied pulse 1214 (η0 act =I measurement R 0 act (SOC,T)).

[0227] The balanced impedance data structures may be stored as data or program instructions in memory local to the source of interest (e.g., a BMS) or may be retrieved from a cloud server using techniques described herein. In some embodiments, a system having the source 206 may perform an evaluation or characterization of the source 206 in the field and use the data to build or revise these data structures.

[0228] FIG. 23 is an example plot of anode potential at equilibrium versus SOC, specifically the maximum allowable potential before deleterious degradation (e.g., lithium deposition) occurs. This anode potential can be used to derive a threshold value for use in determining whether too much or too little current is being applied during charging stages 1120 and 1130. Here, the SOC values ​​are divided into three ranges (10-30%, 31-60%, and 61-90%), each with an associated maximum anode overvoltage value (V1, V2, V3, respectively). This is a relatively simple depiction of the ranges for illustration purposes, but more complex depictions can be used, such as four or more ranges, maximum values ​​for each individual SOC, linear or nonlinear models of maximum potential, etc. The threshold function f(SOC) can be derived according to (12)-(15). (12) η conc_activation (SOC) <f(SOC) (13) conc_Nernst (SOC)<1 / αf(SOC) (14)n conc (SOC)<[1+(1 / α)]f(SOC) (15)f(SOC) = [R′η conc max anode (SOC)] / [1+(1 / α)] where R' is a ratio coefficient that depends on the distribution of the overall activation impedance between the anode and the cathode. For example, an R' value of 2 corresponds to an impedance that is evenly distributed between the anode and the cathode. The value of R' can be selected based on testing or modeling of the actual chemistry of the source of interest and their electrodes. Since f(SOC) is scaled by the term [1+(1 / α)], the charging process scales with η conc_activation can be adjusted using only η conc_Nernst The use of is not required, but may be used in some embodiments as desired. Table 3 includes example values ​​of f(SOC) based on an R' of 2, a value of 0.5 for α, and values ​​of 210 mV, 180 mV, and 85 mV for V1, V2, and V3. [Table 3]

[0229] In other embodiments, f(SOC) is calculated using the concentration gradient (c 0 / c*). A charging step 1120 or 1130 can be performed and the concentration gradient can be periodically evaluated and the charging parameters adjusted to ensure that the gradient does not become too large.

[0230] FIG. 24A is a flow diagram depicting an exemplary embodiment of a charging method 2400 that can be used with aspects of protocol 1100 that employ additional concentration gradient control (e.g., adapting to feedback of voltage shifts induced by concentration changes). Method 2400 can be implemented by and under the direction of controller 2101. In step 2402, target source 206 is charged using either pulse charging or constant current charging (e.g., stages 1120 or 1130, respectively). The charging current is preferably at a high level (for fast charging), such as greater than 1 C (1C) or 2C for source 206. Typically, normal charging is performed within the constraints of manufacturer recommended current, cutoff voltage, and time, and the actual C limit associated with normal charging varies based on those recommendations.

[0231] During the charging step 2402, intermittently, the controller 2101 calculates η* according to (10). act -η 0 act η conc_activation An evaluation step 2404 can be initiated to determine the intermittent interval. The intermittent interval can be based on elapsed time (e.g., every 10 seconds, 20 seconds, 30 seconds, etc.), can be based on the occurrence of a charging or temperature condition (e.g., every 1% change in SOC level, every 1 degree increase in temperature), can be based on the amount of change in applied voltage required to drive a desired current, or can be based on the amount of change in applied current based on a constant applied voltage (e.g., indicative of a concentration change).

[0232] In an exemplary embodiment, η conc_activation To determine R 0 act The (SOC,T) values ​​can be identified from a corresponding data structure (e.g., Table 2) using the SOC and temperature values ​​that the source of interest 206 has (or has recently had), and these values ​​can be evaluated contemporaneously with step 2404 or can be estimated based on previous evaluations of the SOC and temperature. 0 act This specific R 0 actIt can be determined by taking the product of the (SOC,T) value and the current of the applied current pulse 1214. act can be determined in any of the manners described herein. For example, R 0 ohmic The (SOC,T) value can be determined from a corresponding data structure (e.g., Table 2) using the SOC and temperature values ​​that the source of interest 206 has (or has recently had). 0 ohmic is this specific R 0 ohmic It can be determined by taking the product of the (SOC,T) value and the current of the applied current pulse 1214. ohmic Considering that the variation of the ohmic voltage drop due to the concentration change is small, η 0 ohmic This η* ohmic The value can be subtracted from the voltage drop measured during T_fall and the resulting difference is η* act Then, η* act From 0 act Subtract η conc_activation can result.

[0233] In step 2406, the controller 2101 determines that the charging current should be adjusted, using η conc_activation The controller 2101 may select an appropriate f(SOC) threshold from a corresponding data structure (e.g., Table 3) based on the current SOC of the target source 206, and define the f(SOC) threshold as η conc_activation can be compared with η conc_activation If f exceeds the threshold, it may indicate that the applied charging current is too high (e.g., creating an overvoltage on the anode that exceeds an acceptable range), and the controller 2101 may reduce the charging current to reduce the overvoltage created on the anode and cathode, or (as in step 1120) reduce f pulseIt may be decided to adjust one or more charging parameters, such as adjusting η , or (if during step 1120) adjusting the duty cycle or pulse width of the charging pulse 1122. conc_activation If η is at or slightly below the threshold, it may indicate an appropriate amount of charging current to be applied, and the controller 2101 may decide to maintain the charging parameters without adjustment. conc_activation If f is significantly below the threshold, it may indicate that the applied charging current is too small (e.g., there is additional overvoltage available on the anode without exceeding the tolerance range), and the controller 2101 may increase the charging current to increase the overvoltage generated on the anode and cathode, or (as in step 1120) f pulse , or (if during step 1120) adjusting the duty cycle or pulse width of the charging pulse 1122.

[0234] In 2408, the controller can determine the adjustment amount and return to the charging step 2402. The adjustment amount can be set to a fixed value. The fixed value can be a relatively small value to conservatively adjust the current during the charging process. Alternatively, the controller 2101 can determine the amount of adjustment, η conc_activation and the f(SOC) threshold can be selected, eg, the adjusted parameter can be scaled by the difference amount.

[0235] The method 2400 continues pulse charging and η 2410 until a target SOC level is reached (step 2410) or until an appropriate transition condition for transitioning from the pulse charging phase 1120 to the constant current charging phase 1130 is reached, as described with respect to the protocol 1100 herein. conc_activation The evaluation and adjustment can be performed iteratively. The constant current charging 1130 is performed by adjusting η conc_activationand intermittent evaluation of charging parameters (e.g., charging current). In this manner, method 2400 can follow one or both of charging phases 1120 and 1130 at high current until the target source reaches a target SOC level.

[0236] 24B is a flow diagram depicting an exemplary embodiment of a pre-heat and charge method 2420 that can be used with aspects of protocol 1100 that employ additional concentration gradient control. Method 2420 can be performed by and under the direction of controller 2101.

[0237] Steps 2422, 2424, and 2426 are used to verify that the target source 206 under equilibrium is in a suitable state for the high current, rapid pulse charging phase 1120, and may be omitted in certain embodiments if not necessary or desirable. In step 2422, the temperature of the target source 206 may be measured and a preheat phase 1110 may be performed to, for example, add the R to the equilibrium impedance data structure. 0 ohmic and R 0 act The temperature of the source 206 can be increased to a value for which data exists. 0 ohmic and η 0 act The measurement of R may be performed by applying a current pulse 1214 and measuring the voltage response 1212 over T_rise (e.g., 50-100 ms). 0 ohmic ' and R 0 act ' is the measured η 0 ohmic and η 0 act and R in the balanced impedance data structure, which can be determined based on the applied current. 0 ohmic and R 0 actThe newly measured R may be compared to an existing value of R (or alternatively, the comparison may be of corresponding ohms and activation voltage). Based on the comparison, the condition to proceed with fast charging is either verified or not verified. If the values ​​are equal, the method 2420 may proceed towards high current fast charging in step 2430. 0 ohmic ' and R 0 act If the ' value (or voltage) is significantly higher (eg, above a threshold), this may indicate significant aging in the target source 206 and a slower charging procedure with normal current may be performed 2428 instead.

[0238] In step 2430, the temperature of the target source 206 can be measured (again, if desired), and a preheat phase 1110 can be performed to raise the temperature of the source 206 to the desired starting temperature of the pulse charging phase 1120 (or phase 1130). In step 2432, the pulse charging phase 1120 can be started or otherwise performed, and in 2434, η conc_activation 24A, the details of which are set forth hereinabove. In this manner, the method 2420 can follow one or both of the charging phases 1120 and 1130 at high current until the source of interest reaches the target SOC level. The controller 2101 can determine in step 2436 whether an adjustment to the charging parameters should be made, and the magnitude of the adjustment can be determined in step 2438, at which point the method 2420 can return to pulse charging in step 2432. Steps 2432, 2434, 2436, and 2438 are similar to steps 2402, 2404, 2406, and 2408 described with respect to FIG. 24A, the details of which are set forth hereinabove. In this manner, the method 2420 can follow one or both of the charging phases 1120 and 1130 at high current until the source of interest reaches the target SOC level.

[0239] The method 2420 continues pulse charging and η until a target SOC level is reached or an appropriate transition condition for transitioning from the pulse charging phase 1120 to the constant current charging phase 1130 is reached. conc_activationThe evaluation and adjustment can be performed iteratively. The constant current charging 1130 also adjusts η conc_activation and intermittent evaluation of charging parameters (e.g., charging current). In this manner, method 2420 can follow one or both of charging phases 1120 and 1130 at high current until the target source reaches a target SOC level, e.g., 80%, as shown in step 2440.

[0240] Referring back to step 2426, in some embodiments, the equilibrium impedance data structure may be updated based on newly collected data. For example, R 0 ohmic ' and R 0 act The re-evaluated value of ' can be compared to the two corresponding values ​​in the equilibrium impedance data structure. ohmic is the R data structure 0 ohmic 'Value and R 0 ohmic Using this scaling factor, R can be derived based on the proportional difference between the 0 ohmic '(SOC,T)=SF ohmic xR 0 ohmic R in the data structure over SOC and temperature, such that (SOC,T) 0 ohmic All of the values ​​can be scaled. Similarly, the scaling factor SF act is the R data structure 0 act 'Value and R 0 act Using this scaling factor, R can be derived based on the proportional difference between the 0 act '(SOC,T)=SF act xR 0 act R in the data structure over SOC and temperature, such that (SOC,T) 0 actAll of the values ​​can be scaled. In this manner, the ohms and activation impedance can be periodically updated over the life of the subject source 206 to ensure accuracy in staying within the allowable anode and cathode overvoltage ranges.

[0241] Methods 2100, 2400, and 2420 may be performed for modular cascaded system 100. Execution of these methods in cascaded system 100 may involve execution of the methods for each energy source in the system individually and discretely. Thus, for a system having N modules, methods 2100, 2400, 2420 may be executed N times (e.g., based on the SOC, temperature, impedance, inductance, and / or thermal characteristics of the individual energy sources of interest) to tailor the method for each particular energy source. The N instances of the methods may be executed simultaneously with one another under the control of control system 102 (either alone or in conjunction with the control unit of the associated charging source 150).

[0242] When implemented within a modular cascaded system 100, the embodiments described herein may be used to charge all such modules of the system, including modules 108-1 through 108-N of each array, and an interconnect module 108IC for all such modules having one, two or more energy sources therein.

[0243] Although many of the embodiments are described herein in the context of current-controlled charging signals (e.g., applied current pulses), all such embodiments may be implemented with voltage-controlled charging signals (e.g., applied voltage pulses) as well.

[0244] All of the foregoing embodiments relating to pulse charging may be implemented in accordance with a pulse width modulation control scheme or a hysteresis-based control scheme, as described herein, with additional constraints on pulse length implemented where applicable so as not to violate the pulse duration requirements of certain embodiments described herein.

[0245] All of the above embodiments relating to fast charging can also be used to discharge the system in a fast manner as well.

[0246] In all of the embodiments described herein, the primary energy source of each module of a particular system can have the same voltage (either standard operating voltage or nominal voltage). Such a configuration simplifies the management and construction of the system. The primary and secondary energy sources can also have the same voltage (standard or nominal). Other configurations can be implemented, such as primary energy sources of different modules of the same system having different voltages (standard or nominal) and primary and secondary energy sources of a module having different voltages (standard or nominal). Still other configurations can be implemented, such as primary energy sources of modules of a system having batteries of primary energy sources that are different chemistries, or modules of a system having batteries of primary energy sources of a first chemistry and secondary energy sources of a second chemistry. The different modules can be based on the arrangement in the system (e.g., modules in a phased array are different from IC modules).

[0247] Various aspects of the present subject matter are described below in review of and / or to complement the previously described embodiments, with emphasis being placed on the interrelationships and compatibility of the following embodiments, in other words, the fact that each feature of the embodiments can be combined with each and every other feature, unless expressly stated or otherwise taught.

[0248] In a first group of embodiments, a method of charging an energy source is provided, the method including: applying a charging signal to the energy source such that a concentration shift occurs in the energy source; measuring a voltage response to a current pulse applied to the energy source; determining from the voltage response an activation overvoltage due to the concentration shift; and determining whether to adjust a parameter of the charging signal based at least in part on the activation overvoltage due to the concentration shift.

[0249] In some embodiments of the first group, the measured voltage response is the voltage drop that occurs after the end of the current pulse over a period of time (T_fall). The measured voltage response includes a first voltage drop due to ohmic losses (η*ohmic) and activation losses (η* act ) may include a second voltage drop of 150 milliseconds or less. conc-activation ) is calculated by subtracting the first voltage drop due to ohmic losses from the measured voltage response to yield a second voltage drop due to activation losses, and 0 act ) to yield the activation overpotential due to concentration shift. The method also includes subtracting the equilibrium voltage loss due to ohmic losses (η 0 ohmic The method can include determining a first voltage drop due to ohmic losses based on a balanced ohmic impedance (R 0 ohmic ) to determine a balanced voltage loss due to ohmic losses. The multiple balanced ohmic impedances may be stored in a memory along with associated state of charge and / or temperature values.

[0250] In some embodiments of the first group, the method further comprises: 0 CT) to determine a balanced voltage loss due to activation loss. The plurality of balanced activation impedances may be stored in a memory with associated state of charge and / or temperature values. The balanced ohmic impedance and the balanced activation impedance are stored in at least one data structure. The at least one data structure may be a data array or a look-up table. The method may include evaluating at least one of a state of charge and a temperature of the energy source, and referencing the memory with the evaluated at least one state of charge and / or temperature to determine the balanced ohmic impedance and the balanced activation impedance. Both the state of charge and the temperature may be evaluated and used in referencing the memory.

[0251] In some embodiments of the first group, the method includes adjusting a parameter of the charging signal, which can be at least one of a charging current amperage, a frequency of pulses of the charging signal, a duty cycle of the pulses of the charging signal, or a duration of the pulses of the charging signal.

[0252] In some embodiments of the first group, determining whether to adjust a parameter of the charging signal based at least in part on the activation overvoltage due to concentration shift includes comparing the activation overvoltage due to concentration shift (ηconc-activation) to a threshold value (f(SOC)). The method can include increasing the charging current amperage if the activation overvoltage is less than the threshold value. The method can include decreasing the charging current amperage if the activation overvoltage exceeds the threshold value. The method can include maintaining the charging current amperage if the activation overvoltage equals the threshold value. The method can include determining the threshold value. Determining the threshold value can include selecting the threshold value based on a current state of charge of the energy source. The method can include referencing a data structure having a plurality of threshold values ​​each associated with one or more state of charge levels. The threshold value can be a function of the activation loss due to concentration shift (η* act ) and Nernst loss due to concentration shift (η*Nernst ) are described. The threshold value may be based on a tolerance range of anode overvoltage or a maximum anode overvoltage. The threshold value may be a voltage value.

[0253] In some embodiments of the first group, the method can include determining at least one of an updated balanced ohmic impedance and an updated balanced activation impedance, comparing the updated balanced ohmic impedance and the updated balanced activation impedance with a corresponding at least one existing balanced ohmic impedance and an existing balanced activation impedance, and determining whether to apply a charge signal. If the updated balanced ohmic impedance and the updated balanced activation impedance are within a range of the corresponding at least one existing balanced ohmic impedance and an existing balanced activation impedance, the method can include determining to apply a charge signal. The method can include evaluating a temperature of the energy source and preheating the energy source to a target temperature before determining the updated balanced ohmic impedance and the updated balanced activation impedance.

[0254] In some embodiments of the first group, the method includes evaluating a temperature of the energy source, pre-heating the energy source to a target temperature, and performing a validation evaluation to determine whether to proceed with charging. The validation evaluation can include measuring a parameter of the energy source at the target temperature, comparing the measured parameter to an existing version of the parameter, and determining whether to proceed with charging.

[0255] In some embodiments of the first group, the applied charging signal is either a plurality of charging pulses or a constant current charging signal.

[0256] In some embodiments of the first group, the energy source is a lithium-ion battery cell.

[0257] In some embodiments of the first group, the energy source is a battery module including multiple lithium ion cells connected together in a series and / or parallel format.

[0258] In some embodiments of the first group, the energy source is a battery in an electric vehicle.

[0259] In a second group of embodiments, a system configured to charge an energy source is provided, the system including the energy source and a controller, the controller configured to control application of a charging signal to the energy source such that a concentration shift occurs in the energy source, control measuring a voltage response to a current pulse applied to the energy source, determine from the voltage response an activation overvoltage due to a concentration shift in the energy source, and determine whether to adjust parameters of the charging signal based at least in part on the activation overvoltage due to the concentration shift.

[0260] In some embodiments of the second group, the controller may be configured to determine the activation overvoltage by subtracting a first voltage drop due to ohmic losses from the measured voltage response to yield a second voltage drop due to activation losses, and subtracting a balanced voltage loss due to activation losses from the second voltage drop due to activation losses to yield an activation overvoltage due to concentration shift. The controller may be configured to determine the first voltage drop due to ohmic losses based on the balanced voltage loss due to ohmic losses. The controller may be configured to determine the balanced voltage loss due to ohmic losses from a balanced ohmic impedance stored in the memory of the controller. The multiple balanced ohmic impedances may be stored in the memory with associated state of charge and / or temperature values.

[0261] In some embodiments of the second group, the controller may be configured to determine the balanced voltage loss due to activation loss from the balanced activation impedance stored in the memory.

[0262] In some embodiments of the second group, the controller may be configured to control evaluation of at least one of a state of charge and a temperature of the battery module and to determine a balanced ohmic impedance and a balanced activation impedance by referencing a memory with the evaluated at least one state of charge and / or temperature.

[0263] In some embodiments of the second group, the controller may be configured to adjust a parameter of the charging signal.

[0264] In some embodiments of the second group, the controller may be configured to compare the activation overpotential due to the concentration shift to a threshold to determine whether to adjust a parameter of the charging signal. The controller may be configured to determine the threshold. The controller may be configured to select the threshold based on a current state of charge of the energy source.

[0265] In some embodiments of the second group, the controller may be configured to determine at least one of an updated balanced ohmic impedance and an updated balanced activation impedance, compare the at least one of the updated balanced ohmic impedance and the updated balanced activation impedance with a corresponding at least one existing balanced ohmic impedance and an existing balanced activation impedance, and determine whether to apply a charging signal.

[0266] In some embodiments of the second group, the controller may be configured to provide an evaluation of a temperature of the battery module, control application of a preheat signal to the battery module to raise the battery module to a target temperature, and perform a validation evaluation to determine whether to charge the battery module. To perform the validation evaluation, the controller may be configured to control measurement of a parameter of the energy source at the target temperature, compare the measured parameter to an existing version of the parameter, and determine whether to charge the energy source based on the comparison.

[0267] In some embodiments of the second group, the charging signal is either a plurality of charging pulses or a constant current charging signal.

[0268] In some embodiments of the second group, the energy source includes a lithium ion battery cell.

[0269] In some embodiments of the second group, the controller includes a processing circuit and a memory having a plurality of instructions that, when executed by the processing circuit, cause the processing circuit to perform or to perform steps of a method.

[0270] In a third group of embodiments, a system configured to charge an energy source is provided, the system including a plurality of converter modules, each converter module including a converter and a battery module coupled to the converter, the battery modules having a plurality of battery cells connected in series and / or parallel and coupled together in at least one array configured to generate a voltage including a superposition of output signals from each of the converter modules; and a control system, the control system configured to control application of a charging signal to each battery module such that a concentration shift occurs in the battery cells of the battery modules, control measurement of a voltage response to the current pulse applied to each battery module, determine from the voltage response an activation overvoltage due to a concentration shift in the battery cells of the battery modules, and determine whether to adjust parameters of the charging signal based at least in part on the activation overvoltage due to the concentration shift.

[0271] In some embodiments of the third group, the measured voltage response is a voltage drop occurring after the end of the current pulse over a period of time. The measured voltage response may include a first voltage drop due to ohmic losses and a second voltage drop due to activation losses. The period of time may be 150 milliseconds or less. The control system may be configured to determine the activation overvoltage by subtracting the first voltage drop due to ohmic losses from the measured voltage response to yield a second voltage drop due to activation losses and subtracting a balanced voltage loss due to activation losses from the second voltage drop due to activation losses to yield an activation overvoltage due to concentration shift. The control system may be configured to determine the first voltage drop due to ohmic losses based on the balanced voltage loss due to ohmic losses. The control system may be configured to determine the balanced voltage loss due to ohmic losses from a balanced ohmic impedance stored in a memory of the control system. The plurality of balanced ohmic impedances are stored in the memory with associated state of charge values ​​and / or temperature values. The control system may be configured to determine the balanced voltage loss due to activation losses from a balanced activation impedance stored in the memory. The memory stores a plurality of balanced activation impedances with associated state of charge and / or temperature values. The memory stores at least one data structure having a balanced ohmic impedance and a balanced activation impedance. The at least one data structure may be a data array or a look-up table. The control system may be configured to control evaluation of at least one of the state of charge and temperature of the battery module and to reference the memory with the evaluated at least one state of charge and / or temperature to determine the balanced ohmic impedance and the balanced activation impedance. The control system may be configured to evaluate both the state of charge and the temperature.

[0272] In some embodiments of the third group, the control system may be configured to adjust a parameter of the charging signal, which may be at least one of a charging current amperage, a frequency of the pulses of the charging signal, a duty cycle of the pulses of the charging signal, or a duration of the pulses of the charging signal.

[0273] In some embodiments of the third group, the control system may be configured to compare the activation overvoltage due to concentration shift to a threshold value to determine whether to adjust a parameter of the charging signal. The control system may be configured to direct an increase in the charging current amperage if the activation overvoltage is less than the threshold value. The control system may be configured to direct a decrease in the charging current amperage if the activation overvoltage is greater than the threshold value. The control system may be configured to direct a maintenance of the charging current amperage if the activation overvoltage is equal to the threshold value. The control system may be configured to determine the threshold value. The control system may be configured to select the threshold value based on a current state of charge of the energy source. The control system may be configured to reference a data structure including a plurality of threshold values ​​each associated with one or more state of charge levels. The threshold value may account for both activation losses due to concentration shift and Nernst losses due to concentration shift. The threshold value may be based on a tolerance range for the anode overvoltage. The threshold value may be a voltage value.

[0274] In some embodiments of the third group, the control system may be configured to determine at least one of an updated balanced ohmic impedance and an updated balanced activation impedance, compare the updated balanced ohmic impedance and the updated balanced activation impedance with the corresponding at least one existing balanced ohmic impedance and the existing balanced activation impedance, and determine whether to apply the charge signal. The control system may be configured to determine to apply the charge signal if the updated balanced ohmic impedance and the updated balanced activation impedance are within a range of the corresponding at least one existing balanced ohmic impedance and the existing balanced activation impedance. The control system may be configured to provide a measurement of the temperature of the battery module and control application of a preheat signal to the battery module to raise the battery module to a target temperature.

[0275] In some embodiments of the third group, the control system may be configured to provide an evaluation of the temperature of the battery module, control application of a preheat signal to the battery module to raise the battery module to a target temperature, and perform a validation evaluation to determine whether to charge the battery module. To perform the validation evaluation, the control system may be configured to control measurement of a parameter of the energy source at the target temperature, compare the measured parameter to an existing version of the parameter, and determine whether to charge the energy source based on the comparison.

[0276] In some embodiments of the third group, the charging signal can be either a plurality of charging pulses or a constant current charging signal.

[0277] In some embodiments of the third group, the battery cells are lithium ion battery cells.

[0278] In some embodiments of the third group, the plurality of converter modules are configured to power a motor of an electric vehicle.

[0279] In a fourth group of embodiments, a method of heating an energy source is provided, the method including determining an inductance and / or impedance of the energy source by application of at least one stimulation signal to the energy source, determining a frequency of the heating signal based on the determined inductance and / or impedance of the energy source, and applying the heating signal at the frequency to the energy source.

[0280] In some embodiments of the fourth group, the heating signal can be configured to heat the energy source without substantially charging the energy source.

[0281] In some embodiments of the fourth group, the heating signal includes a series of pulses of alternating polarity.

[0282] In some embodiments of the fourth group, the heating signal does not apply a net charge to the energy source.

[0283] In some embodiments of the fourth group, an inductance is determined, the inductance being based on measurements across at least a first node and a second node, the inductance including the inductance of the energy source and the conductive path between the first node and the second node. The inductance may be determined either using spectroscopy or by applying a current pulse and measuring the voltage response.

[0284] In some embodiments of the fourth group, the energy source may be a battery pack including a plurality of battery cells, and the inductance includes the inductance of the battery cells, conductive paths between the battery cells, and conductive paths between the measurement node and one or more battery cells.

[0285] In some embodiments of the fourth group, the method may be performed for a system having a plurality of converter modules, each converter module including a converter and an energy source coupled to the converter, the energy source being a battery module having a plurality of battery cells connected in series and / or parallel, the plurality of converter modules being coupled together in at least one array configured to generate a voltage including a superposition of output signals from each of the converter modules. The method may include determining an inductance and / or impedance of each energy source of the system by application of at least one stimulus signal to each energy source, determining, for each energy source, a frequency of a heating signal based on the determined inductance and / or impedance of each energy source, and applying, for each energy source, the heating signal to each energy source at the frequency determined for that energy source.

[0286] In some embodiments of the fourth group, an impedance may be determined, and the impedance may be a total impedance of the energy source.

[0287] In some embodiments of the fourth group, the method includes determining an activation impedance and a total impedance of the energy source.

[0288] In some embodiments of the fourth group, the frequency may be determined to be greater than a minimum frequency based on impedance and not greater than a maximum frequency based on inductance. Both the inductance and the impedance are determined and used to select the frequency. The frequency may be selected from a data structure based on the determined inductance and impedance. The data structure may be a look-up table.

[0289] In a fifth group of embodiments, a method of charging an energy source is provided, the method including determining an inductance and / or impedance of the energy source by application of at least one stimulation signal to the energy source, determining a frequency of a charging signal based on the determined inductance and / or impedance of the energy source, and applying the charging signal at the frequency to the energy source.

[0290] In some embodiments of the fifth group, the charging signal includes a plurality of charging pulses.

[0291] In some embodiments of the fifth group, an inductance is determined, the inductance being based on measurements across the first node and the second node, the inductance including the inductance of the energy source and the conductive path between the first node and the second node. The inductance may be determined either using spectroscopy or by applying a current pulse and measuring the voltage response.

[0292] In some embodiments of the fifth group, the energy source may be a battery pack having a plurality of battery cells, and the inductance includes an inductance of the battery cells, a conductive path between the battery cells, and a conductive path between the measurement node and one or more battery cells.

[0293] In some embodiments of the fifth group, the method may be performed for a system including a plurality of converter modules, each converter module having a converter and an energy source coupled to the converter, the energy source being a battery module having a plurality of battery cells connected in series and / or parallel, the plurality of converter modules coupled together in at least one array configured to generate a voltage including a superposition of output signals from each of the converter modules. The method may include determining an inductance and / or impedance of each energy source of the system by application of at least one stimulus signal to each energy source, determining, for each energy source, a frequency of a charging signal based on the determined inductance and / or impedance of each energy source, and applying, for each energy source, a charging signal to each energy source at the determined frequency for that energy source.

[0294] In some embodiments of the fifth group, an impedance is determined, the impedance being the total impedance of the energy source.

[0295] In some embodiments of the fifth group, the method includes determining an activation impedance and a total impedance of the energy source.

[0296] In some embodiments of the fifth group, the frequency may be determined to be greater than a minimum frequency based on impedance and not greater than a maximum frequency based on inductance. Both the inductance and the impedance are determined and used to select the frequency. The frequency may be selected from a data structure based on the determined inductance and impedance. The data structure may be a look-up table.

[0297] In a sixth group of embodiments, a method of charging an energy source is provided, the method including: evaluating a plurality of impedances of the energy source, the plurality of impedances including a total impedance and a non-ohmic impedance; and applying a charging signal to the energy source, the charging signal including pulses at a frequency that maintains the non-ohmic impedance above a threshold percentage of the total impedance.

[0298] In some embodiments of the sixth group, the threshold percentage may be 50%.

[0299] In some embodiments of the sixth group, the threshold percentage may be 60%.

[0300] In some embodiments of the sixth group, the non-ohmic impedance includes an activation impedance and a Warburg impedance.

[0301] In some embodiments of the sixth group, the charging signal may be applied at a time-averaged C rate of two or more.

[0302] In some embodiments of the sixth group, the charging signal may be applied with a 50% duty cycle.

[0303] In some embodiments of the sixth group, the charging signal may be applied with a duty cycle of 40-60%.

[0304] In a seventh group of embodiments, a method of heating an energy source is provided, the method comprising: evaluating an impedance of the energy source during a pre-heating phase of the energy source, the pre-heating phase including applying a heating signal at a first frequency to the energy source; determining a second frequency of the heating signal based on the evaluated impedance; and applying the heating signal at the second frequency to the energy source.

[0305] In some embodiments of the seventh group, the heating signal can be configured to heat the energy source without substantially charging the energy source.

[0306] In some embodiments of the seventh group, the heating signal includes a series of pulses of alternating polarity.

[0307] In some embodiments of the seventh group, the heating signal does not apply a net charge to the energy source.

[0308] In an eighth group of embodiments, a method of charging in a system is provided, the system including a plurality of converter modules, each converter module including a converter and an energy source coupled to the converter, the energy source being a battery module having a plurality of battery cells connected in series and / or parallel, the plurality of converter modules being coupled together in at least one array configured to generate a voltage including a superposition of output signals from each of the converter modules, the method including: for each energy source, individually evaluating an impedance of the energy source during a pulse charging phase of the system, the pulse charging phase including applying a pulse charging signal to the energy source; determining an adjusted frequency for the pulse charging signal of at least one energy source based on the evaluated impedance for that energy source; and applying the pulse charging signal to the at least one energy source at the adjusted frequency.

[0309] In some embodiments of the eighth group, the impedance may be a total impedance of the energy source.

[0310] In some embodiments of the eighth group, for each energy source, individually assessing the impedance of the energy source includes assessing, for each energy source, an activation impedance and a total impedance, and the method can include determining an adjusted frequency of the pulsed charging signal of at least one energy source based on the assessed activation and total impedance of that energy source.

[0311] In a ninth group of embodiments, methods related to charging an energy source are provided, the methods including evaluating a parameter of the energy source, identifying a frequency corresponding to the evaluated parameter by referencing a data structure, and applying a signal to the energy source at the identified frequency, wherein the signal may be configured to either charge the energy source or heat the energy source without substantially charging the energy source.

[0312] In some embodiments of the ninth group, the parameter may be the impedance of the energy source.

[0313] In some embodiments of the ninth group, the parameter may be an identifier of the energy source.

[0314] In a tenth group of embodiments, a method related to charging an energy source is provided, the method including evaluating a parameter, the parameter being a state of charge of the energy source, an impedance of the energy source, a temperature of the energy source, or a temperature external to the energy source, determining an amplitude of a heating signal based on at least the evaluated parameter, and applying the heating signal at the amplitude to the energy source.

[0315] In some embodiments of the tenth group, the parameter may be an impedance of the energy source, and determining the amplitude of the heating signal based at least on the evaluated impedance includes reducing the amplitude if the evaluated impedance is greater than an impedance threshold.

[0316] In some embodiments of the tenth group, the parameter may be an impedance of the energy source, and determining an amplitude of the heating signal based at least on the assessed impedance includes increasing the amplitude if the assessed impedance is less than an impedance threshold.

[0317] In some embodiments of the tenth group, the energy source includes a lithium ion battery cell.

[0318] In some embodiments of the tenth group, the energy source may be a battery module including multiple battery cells connected in series and / or in parallel.

[0319] In some embodiments of the tenth group, the method may be performed in a system including a control system, multiple cascaded converter modules, and an energy source, and the method may be performed independently for each energy source and simultaneously by multiple converter modules.

[0320] In an eleventh group of embodiments, a method of heating an energy source is provided, the method comprising applying an electrical heating signal to the energy source, the electrical heating signal comprising an alternating sequence of charge and discharge pulses at a frequency that heats ohmic portions of the energy source without substantially heating non-ohmic portions of the energy source.

[0321] In some embodiments of the eleventh group, the energy source includes a lithium ion cell.

[0322] In some embodiments of the eleventh group, the electrical heating signal may be applied while monitoring the temperature of the energy source and the temperature of the environment external to the energy source. The electrical heating signal may be applied such that a gradient between the temperature of the energy source and the environment external to the energy source is maintained within a limit value. The limit value may be 30 degrees Celsius, or the limit value may be 20 degrees Celsius.

[0323] In some embodiments of the eleventh group, the method can be performed without simultaneously cooling the energy source with a cooling device.

[0324] In a twelfth group of embodiments, a method related to charging an energy source is provided, the method including: evaluating a charge level of a target energy source to be charged; evaluating at least one of an impedance of the energy source or an inductance of a charging path including the energy source; selecting a protocol setting for execution of a heating and / or charging protocol on the target source based on the evaluated impedance and / or inductance; and executing the protocol on the target source.

[0325] In some embodiments of the twelfth group, impedance is assessed and the method includes assessing at least one of a total impedance, an activation impedance, or an ohmic impedance of the target source. The impedance can be measured using electrochemical impedance spectroscopy. The impedance can be measured by applying a stimulation signal and measuring a voltage response.

[0326] In some embodiments of the twelfth group, inductance is evaluated.

[0327] In some embodiments of the twelfth group, the method can include evaluating at least one thermal aspect of the target source. The at least one thermal aspect can be a temperature of the target source or a temperature of an ambient environment external to the target source. The at least one thermal aspect can be a thermal resistance or a thermal capacitance of the target source. The thermal resistance is evaluated by applying one or more preheat pulses to the target source to generate an amount of localized heating against which the thermal resistance is evaluated and against which the thermal resistance is determined.

[0328] In some embodiments of the twelfth group, the method can include recognizing a model type, product class, or chemistry identifier of the target source. The method can include referencing a data structure including parameters of the recognized model type, product class, or chemistry identifier of the target source, and selecting a protocol setting based on the parameters. The method can include selecting a protocol setting by referencing a data structure including protocol settings for the model type, product class, or chemistry identifier of the target source. The method can include sending the recognized model type, product class, or chemistry identifier of the target source to a cloud-based server, and receiving parameters or protocol settings of the target source from the cloud-based server.

[0329] In some embodiments of a twelfth group, the method may include reading an identifier of the target source, sending the identifier to a cloud-based server, and receiving parameters or protocol settings of the target source from the cloud-based server.

[0330] In some embodiments of the twelfth group, the method may include reading parameters or protocol settings of the target source from a local memory of the target source.

[0331] In some embodiments of the twelfth group, the method can include performing a verification of whether a preheating phase and / or a charging phase can be performed on the target source. The verification can include comparing a parameter of the target source to a verification condition. The parameter can be an activation impedance.

[0332] In some embodiments of the twelfth group, selecting the protocol setting includes selecting at least one of a frequency value or range of the heating signal, a frequency value or range of the pulsed charging signal, a current or voltage amplitude value or range of the heating signal, a current or voltage amplitude value or range of the pulsed charging signal, a duty cycle of the heating signal, a duty cycle of the pulsed charging signal, a pulse width of the heating signal, or a pulse width of the pulsed charging signal.

[0333] In some embodiments of the twelfth group, the method may include performing a pre-heating step of the protocol on the target source.

[0334] In some embodiments of the twelfth group, the method may include performing a pulse charging phase of the protocol on the target source.

[0335] In some embodiments of the twelfth group, the method may include performing a constant current charging phase of the protocol on the target source.

[0336] In some embodiments of the twelfth group, the protocol includes pre-heating the target source, pulse-charging the target source, and constant current charging the target source.

[0337] In some embodiments of the twelfth group, the target source may be a battery module in an electric vehicle.

[0338] In some embodiments of the twelfth group, the method may be performed by or under the direction of a controller or control system.

[0339] In some embodiments of the twelfth group, the target source includes a lithium ion battery cell.

[0340] In some embodiments of the twelfth group, the target source may be a microbattery module having multiple lithium ion battery cells connected in series and / or parallel.

[0341] As used herein, the term "module" refers to one of two or more devices or subsystems within a larger system. A module can be configured to operate in combination with other modules of similar size, functionality, and physical arrangement (e.g., location of electrical terminals, connectors, etc.). Modules with the same functionality and energy source can be configured the same (e.g., size and physical arrangement) as all other modules in the same system (e.g., rack or pack), while modules with different functionality or energy sources can differ in size and physical arrangement. Each module can be, but is not required to be, physically removable and replaceable with respect to other modules in the system (e.g., like the wheels of a car, or the blades of an information technology (IT) blade server). For example, a system can be packaged in a common housing that does not permit removal and replacement of any one module without disassembling the entire system. However, any and all embodiments herein can be configured such that each module is removable and replaceable with respect to other modules in any convenient manner without disassembling the system.

[0342] The term "master control device" is used broadly herein and does not require the implementation of any particular protocol, such as a master and slave relationship between any other device, such as a local control device.

[0343] The term "output" is used broadly herein and does not preclude it from functioning in a bidirectional manner as both an output and an input. Similarly, the term "input" is used broadly herein and does not preclude it from functioning in a bidirectional manner as both an input and an output.

[0344] The terms "terminal" and "port" are used broadly herein and may be either unidirectional or bidirectional, may be input or output, and do not require a particular physical or mechanical structure such as a female or male configuration.

[0345] The processing circuitry may include one or more processors, microprocessors, controllers, and / or microcontrollers, each of which may be separate or stand-alone chips, or may be distributed among (and portions of) several different chips. Any type of processing circuitry may be implemented, including but not limited to, personal computing architectures (such as those used in desktop PCs, laptops, tablets, etc.), programmable gate array architectures, proprietary architectures, custom architectures, etc. The processing circuitry may include digital signal processors, which may be implemented in hardware and / or software. The processing circuitry may execute software instructions stored on memory, which cause the processing circuitry to take many different actions and control other components.

[0346] The processing circuitry may also execute other software and / or hardware routines. For example, the processing circuitry may interface with the communications circuitry and perform analog to digital conversion, encoding and decoding, other digital signal processing, multimedia functions, conversion of data to a format suitable for presentation to the communications circuitry (e.g., in-phase and quadrature), and / or cause the communications circuitry to transmit data (wired or wireless).

[0347] The processing circuitry may also be adapted to execute an operating system and any software applications and to perform other functions thereof not related to processing received and transmitted communications.

[0348] Computer program instructions for performing operations according to the described subject matter may be written in any combination of one or more languages, including computer and programming languages, including, but not limited to, a non-exhaustive list of examples, Hardware Description Languages ​​(HDLs), SystemC, C, C++, C#, Objective-C, Matlab, Simulink, SystemVerilog, SystemVHDL, Handel-C, Python, Java, JavaScript, Ruby, HTML, Smalltalk, Transact-SQL, XML, PHP, Golang (Go), the "R" language, and Swift, to name a few.

[0349] The memory, storage, and / or computer-readable media may be shared by one or more of the various functional units presented, or distributed among two or more of them (e.g., as separate memories residing in different chips). A memory may also reside on its own separate chip.

[0350] To the extent that an embodiment disclosed herein includes or operates in conjunction with a memory, storage, and / or computer readable medium, the memory, storage, and / or computer readable medium is non-transitory. Thus, to the extent that the memory, storage, and / or computer readable medium is covered by one or more claims, the memory, storage, and / or computer readable medium is only non-transitory. As used herein, the terms "non-transitory" and "tangible" are intended to describe memory, storage, and / or computer readable medium other than propagating electromagnetic signals, but are not intended to limit the type of memory, storage, and / or computer readable medium in terms of permanence of storage or otherwise. For example, "non-transitory" and / or "tangible" memory, storage, and / or computer readable media encompasses volatile and non-volatile media, such as random access media (e.g., RAM, SRAM, DRAM, FRAM, etc.), read-only media (e.g., ROM, PROM, EPROM, EEPROM, Flash, etc.), and combinations thereof (e.g., hybrid RAM and ROM, NVRAM, etc.), and variations thereof.

[0351] It should be noted that all features, elements, components, functions, and steps described with respect to any embodiment provided herein are intended to be freely combinable and replaceable with those from any other embodiment. If a particular feature, element, component, function, or step is described with respect to only one embodiment, it should be understood that the feature, element, component, function, or step can be used with all other embodiments described herein, unless otherwise specified. Thus, this paragraph serves as a preamble and written support for the introduction of claims that combine features, elements, components, functions, and steps from different embodiments, or replace features, elements, components, functions, and steps from one embodiment with features, elements, components, functions, and steps from another embodiment, even if the following description does not specify that such combinations or substitutions are possible in a particular example. It is expressly recognized that an explicit enumeration of all possible combinations and permutations would be unduly burdensome, especially considering that the permissibility of each and every such combination and permutation would be readily recognized by a person skilled in the art.

[0352] As used in this specification and the appended claims, the singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0353] While the embodiments are susceptible to various modifications and alternative forms, specific examples of which are shown in the drawings and described in detail herein. It is to be understood, however, that these embodiments are not limited to the particular forms disclosed, but on the contrary, these embodiments are intended to encompass all modifications, equivalents, and alternatives falling within the spirit of the present disclosure. Furthermore, any feature, function, step, or element of the embodiments may be recited or added to the claims, as well as any negative limitations that define the scope of the invention in the claims, with any feature, function, step, or element not within its scope.

Claims

1. A method for charging an energy source, Applying a charging signal to the energy source such that a concentration shift occurs within the energy source, Measuring the voltage response to the current pulse applied to the energy source, From the voltage response, the activation overpotential due to the concentration shift is determined, A method comprising determining whether to adjust the parameters of the charging signal based at least partially on the activation overvoltage due to the concentration shift.

2. The method according to claim 1, wherein the measured voltage response is a voltage drop that occurs after the termination of the current pulse over a period (T_fall).

3. The measured voltage response is the ohmic loss (η* ｏｈｍｉｃ ) First voltage drop and activation loss (η* ａｃｔ The method according to claim 2, comprising a second voltage drop due to ).

4. The method according to claim 2, wherein the period is 150 milliseconds or less.

5. The activation overpotential (η) due to the concentration shift ｃｏｎｃ－ａｃｔｉｖａｔｉｏｎ )but, The first voltage drop due to ohmic loss is subtracted from the measured voltage response to obtain the second voltage drop due to activation loss. From the second voltage drop due to activation loss, the equilibrium voltage loss due to activation loss (η) ０ ａｃｔ The method according to claim 3, wherein the activation overpotential due to the concentration shift is determined by subtracting ) from the above.

6. (1) Balanced voltage loss due to ohmic loss (η ０ ｏｈｍｉｃ The method according to claim 5, further comprising: (2) determining the first voltage drop due to ohmic loss based on (1) a balanced activation impedance (R0CT) stored in memory, or (3) determining the balanced voltage loss due to activation loss from the balanced activation impedance (R0CT) stored in memory.

7. From the balanced ohmic impedance (R) stored in the memory ０ ｏｈｍｉｃ The method according to claim 6, further comprising determining the balanced voltage loss due to ohmic loss from).

8. The method according to claim 7, wherein multiple balanced ohmic impedances are stored in memory along with associated charge state values ​​and / or temperature values.

9. The method according to claim 6, wherein multiple equilibrium activation impedances are stored in memory along with associated charge state values ​​and / or temperature values.

10. The method according to claim 9, wherein the balanced ohm impedance and the balanced activation impedance are stored in at least one data structure.

11. The method according to claim 6, further comprising evaluating at least one of the charge state and temperature of the energy source, and determining the balanced ohm impedance and balanced activation impedance by referring to the memory with the evaluated at least one of the charge state and / or temperature.

12. The method according to claim 11, wherein both the charge state and temperature are evaluated and used when accessing the memory.

13. The method according to claim 1, further comprising adjusting the parameter of the charging signal, wherein the parameter is at least one of the following: the charging current in amperes, the frequency of the pulses of the charging signal, the duty cycle of the pulses of the charging signal, or the duration of the pulses of the charging signal.

14. Whether to adjust the parameters of the charging signal based at least partially on the activation overvoltage due to the concentration shift is to determine whether to adjust the parameters of the charging signal. The activation overpotential (η) due to the concentration shift ｃｏｎｃ－ａｃｔｉｖａｔｉｏｎ The method according to claim 1, comprising comparing ) with a threshold (f(SOC)).

15. The method according to claim 14, further comprising: (1) increasing the charging current amperage when the activation overvoltage is less than the threshold; (2) decreasing the charging current amperage when the activation overvoltage exceeds the threshold; or (3) maintaining the charging current amperage when the activation overvoltage is equal to the threshold.

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