Patent Publication Number: US-11025073-B2

Title: Module maintenance system

Description:
CROSS-REFERENCE TO RELATED APPLICATION(S) 
     This application is a continuation of U.S. Pat. No. 10,431,993, issued Oct. 1, 2019, and titled “Module Maintenance System,” which is a divisional of U.S. Pat. No. 10,063,069, issued Aug. 28, 2018, and titled “Module Maintenance System,” which is a continuation-in-part of U.S. Patent Application Publication No. 2015/0086825, published on Mar. 26, 2015, and titled “Module Backbone System,” which claims priority to U.S. Provisional Patent Application No. 61/960,715, filed Sep. 24, 2013, and titled “Module Backbone System.” Additionally, U.S. Pat. No. 10,063,069 claims priority to U.S. Provisional Application No. 61/997,186, filed on May 23, 2014, and titled “Module Maintenance System.” Each patent and application listed above is incorporated herein by reference in its entirety. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a battery system (e.g., battery pack), particularly a battery system for high voltage applications (e.g., 480 volts). 
     2. Description of Related Art 
     Some battery systems may use multiple battery cells. In such systems, battery cells may have different electrical characteristics that may impact a performance of the battery system. 
     Therefore, there is a need in the art for a battery system that may account for electrical characteristics of a battery cell. 
     SUMMARY OF THE INVENTION 
     The proposed invention is directed to a battery system. In some embodiments, the battery system may include a battery module formed of twelve cells, but this technology can use a battery module having any number of battery cells. In one example, a battery module has a nominal voltage of 40 volts (V), 260 ampere-hour (Ah), and 10 kilowatt hour (kWh). In the example, a battery cell of the battery module may have a nominal voltage of 3.33 volts (V). It should be understood that embodiments may use any suitable battery cell types, manufacturers, technologies, and the like. 
     Embodiments include a battery module, a rig, and a charging device. The battery module includes an enclosure and at least a first battery cell and a second battery cell. The first and second battery cells are disposed in a cavity of the enclosure. The rig includes a lid and a set of buses. The set of buses are attached to the lid. The charging device is for charging the first and second battery cells. The battery module has a series configuration and a parallel configuration. In the series configuration, the lid of the rig is spaced apart from the enclosure and the set of buses of the rig are spaced apart from the first and second battery cells. In the series configuration, one or more bus bars couple the first and second battery cells in series and the charging device modifies charge levels of the first and second battery cells using the one or more bus bars. In the parallel configuration, the lid of the rig attaches to the enclosure of the battery module such that the set of buses of the rig couple to the first and second battery cells and the charging device modifies charge levels of the first and second battery cells using the set of buses. 
     In one aspect, an apparatus includes a battery module, a rig, and a charging device. The battery module includes at least a first battery cell and a second battery cell. The rig includes a set of buses for connecting with the first and second battery cells. The charging device includes a bulk output and an equalization output. The battery module has a series configuration and a parallel configuration. In the parallel configuration, the rig is disposed onto the battery module such that the set of buses couple the first and second battery cells in parallel. In the parallel configuration, the equalization output is coupled to the set of buses and the charging device outputs a first voltage to the equalization output to equalize charge levels of the first and second battery cells. In the series configuration, one or more bus bars couple the first and second battery cells in series with the bulk output and the charging device outputs a second voltage to the bulk output to modify charge levels of the first and second battery cells. The second voltage is greater than the first voltage. 
     In another aspect, an apparatus includes a battery module and a rig. The battery module including an enclosure and at least a first battery cell and a second battery cell. The first and second battery cells are disposed in a cavity of the enclosure. The first battery cell includes a first anode and a first cathode and the second battery cell includes a second anode and a second cathode. The rig includes a lid, a first bus having a first set of contact elements, and a second bus having a second set of contact elements. The lid is secured onto the cavity such that the first set of contact elements are coupled to the first anode and the second anode. The lid is secured onto the cavity such that the second set of contact elements are coupled to the first cathode and the second cathode. 
     Other systems, methods, features and advantages of the invention will be, or will become, apparent to one of ordinary skill in the art upon examination of the following figures and detailed description. It is intended that all such additional systems, methods, features and advantages be included within this description and this summary, be within the scope of the invention, and be protected by the following claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention can be better understood with reference to the following drawings and description. The components in the figures are not necessarily to scale, emphasis instead being placed upon illustrating the principles of the invention. Moreover, in the figures, like reference numerals designate corresponding parts throughout the different views. 
         FIG. 1  is a schematic view of a module maintenance system, in accordance with an exemplary embodiment; 
         FIG. 2  is a schematic view of a charging device, in accordance with an exemplary embodiment; 
         FIG. 3  is a schematic view of a module maintenance system in a first arrangement, in accordance with an exemplary embodiment; 
         FIG. 4  is a schematic view of a module maintenance system in a second arrangement, in accordance with an exemplary embodiment; 
         FIG. 5  is a schematic view of a module maintenance system in a third arrangement, in accordance with an exemplary embodiment; 
         FIG. 6  is a schematic view of a module maintenance system in a fourth arrangement, in accordance with an exemplary embodiment; 
         FIG. 7  is a schematic view of a module maintenance system in a fifth arrangement, in accordance with an exemplary embodiment; 
         FIG. 8  is a schematic view of a battery module, in accordance with an exemplary embodiment; 
         FIG. 9  is a schematic view of bus bars connecting battery cells of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 10  is a schematic view of a rig for connecting battery cells of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 11  is an exploded view of the rig of  FIG. 10 , in accordance with an exemplary embodiment; 
         FIG. 12  is a schematic view of contact elements of the rig of  FIG. 10 , in accordance with an exemplary embodiment; 
         FIG. 13  is a schematic view of positioning the rig of  FIG. 10  on an enclosure of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 14  is a schematic view of coupling contact elements of the rig of  FIG. 10  to bus bars of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 15  is a schematic view of contact elements of the rig of  FIG. 10  being held in direct contact with bus bars of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 16  is a schematic view of the rig of  FIG. 10  being disposed onto an enclosure of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 17  is a schematic view of a module maintenance system having the battery module in a series configuration, in which a charging device is in a discharging state to discharge the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 18  is a schematic view of a module maintenance system after discharging the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 19  is a schematic view of a module maintenance system having the battery module in a series configuration, in which a charging device is in a charging state to bulk charge a series string of battery cells of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 20  is a schematic view of a module maintenance system after bulk charging a series string of battery cells of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; 
         FIG. 21  is a schematic view of a module maintenance system having the battery module in a parallel configuration, in which a charging device uses a rig to charge each battery cell of the battery module of  FIG. 8 , in accordance with an exemplary embodiment; and 
         FIG. 22  is a schematic view of a module maintenance system after charging each battery cell of the battery module of  FIG. 8 , in accordance with an exemplary embodiment. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments may simplify maintenance (e.g., charge, discharge, battery cell balancing, etc.) of a battery module containing a set of battery cells (e.g., 12 battery cells). For example, a module maintenance system may permit bulk charging (e.g., charging the battery cells in series) by connecting a bulk output of a charging device to terminals of a battery module. In the example, a module maintenance system may also permit an equalization of voltages of the battery cells of the battery module by securing a rig onto the battery module and connecting an equalization output of the charging device to the rig. 
     A module maintenance system may include any suitable components to facilitate maintenance of battery modules. Referring to  FIG. 1 , module maintenance system  100  includes charging device  102 , battery module  104 , battery module  106 , and alternating current (AC) supply (e.g., electric grid connection)  110 . In other embodiments, a module maintenance system may include different components. For example, in some embodiments, charging device  102  of module maintenance system  100  charges a single battery module (e.g.,  104  or  106 ). In another example, as shown in  FIG. 1 , module maintenance system  100  may include data port  134  to permit access to one or more networks  144  (e.g., internet), remote terminal  142 , and remote data store  140 , as described further below. 
     The AC supply  110  may be any voltage level or current capacity. For example, the AC supply  110  may be a 480/600 volt AC voltage. In another example, the AC supply  110  may be a 277/480 volt AC voltage. In some examples, the AC supply  110  may be a 347/600 volt AC voltage. The AC supply  110  may be part of a commercial grid. For example, the AC supply  110  may include a regional transmission network and be operated at a particular frequency (e.g., 50 Hz, 60 Hz, etc.) The AC supply  110  may use various numbers of phases (e.g., single phase, three phase, etc.). 
     The battery module may be configured to use any suitable number of battery cells. In some embodiments, a battery module (e.g.,  104 ,  106 ), etc.) may include two or more battery cells. For example, battery module  104  may include sixteen battery cells, twelve battery cells, eight battery cells, and the like. As used herein, a battery cell may use any suitable battery technology. Examples of a battery cell include capacitors, ultra-capacitors, and electrochemical cells. Examples of electrochemical cells include primary (e.g., single use) and secondary (e.g., rechargeable). Examples of secondary electrochemical cells include lead-acid, valve regulated lead-acid (VRLA), gel, absorbed glass mat (AGM), nickel-cadmium (NiCd), nickel-zinc (NiZn), nickel metal hydride (NiMH), lithium-ion (Li-ion), and the like. A battery cell may have various voltage levels. For example, a battery cell of battery module  104  may have a voltage of less than 40 volts, less than 20 volts, less than 10 volts, less than 5 volts, 3.3 volts, less than 3.3 volts, and the like. Similarly, the battery cell may have various energy capacity levels. For example, a battery cell of battery module  104  may have a capacity of more than 13 ampere-hour, more than 10 ampere-hour, more than 20 ampere-hour, more than 25 ampere-hour, and the like. 
     The charging device  102  may include any suitable components to facilitate a maintenance of a battery module (e.g.,  104 ,  106 , etc.). Referring to  FIG. 1 , charging device  102  may include battery maintenance system (BMS) controller  120 , parallel section  122 , series section  124 , and local terminal  126  (e.g., computing device). In other embodiments, charging device  102  may be different. For example, local terminal  126  may be omitted. 
     In those instances where a local terminal is included, any suitable technology may be used. As used herein, a terminal may include to computing resources of a single computer, a portion of the computing resources of a single computer, and/or two or more computers in communication with one another. For example, local terminal  126  may be a single computer (desktop, laptop, notebook, etc.), server, mobile device (e.g., tablet, smart phone, etc.), and the like. In some embodiments, any of these resources may be operated by one or more human users. In some embodiments, a terminal may also include one or more storage devices including, but not limited to, magnetic, optical, magneto-optical, and/or memory, including volatile memory and non-volatile memory. For example, local terminal  126  may include a solid state drive and non-volatile memory. 
     In some embodiments, the local terminal may be configured to determine electrical characteristics of one or more battery cells of a battery module. In some embodiments, the local terminal may measure a charge and/or discharge rate of battery module. In some embodiments, the local terminal may utilize one or more sensor circuits. An example of a sensor circuit may include one or more features described in Kasaba et al., U.S. patent application Ser. No. 14/529,853, filed on Oct. 31, 2014, and titled “System and Method for Battery Pack Charging and Remote Access,” the entirety of which is incorporated herein by reference. For example, a sensor circuit may include a voltage sensor and/or a current sensor. In the example, local terminal  126  may facilitate measurement and recording of a discharge rate and/or a charge rate of a battery cell of battery module  104  and/or battery module  106  using such a sensor circuit. Moreover, in the example, local terminal  126  may store data related to the measurements and/or rates in data store  150  and/or transmit the data related to the measurements and/or rates to remote data store  140  using one or more networks  144 . In some embodiments, the controller may modify a charging and/or discharging rate of a battery cell of battery module to determine electrical characteristics of the battery cell. For example, controller  120  may rapidly charge and/or discharge battery cell  912  to facilitate the testing of electrical characteristics of battery cell  912  as well as battery module  800 . 
     The battery maintenance controller  120  may include one or more processors and have access to memory including instructions to operate charging device  102 . For example, controller  120  may be configured to interact with local terminal  126  to transmit a log of data store  150 . In another example, controller  120  may be configured to receive control instructions and to transmit the control instructions to parallel section  122  and/or series section  124 . 
     The one or more networks  144  may include any number of devices and may use various protocols. In some embodiments, one or more networks  144  may include a connection to an internet service provider and utilize an internet protocol suite (e.g., TCP/IP). As shown in  FIG. 1 , charging device  102  may include data port  134  to connect the charging device  102  with remote terminal  142  and/or the remote data store  140  using the one or more networks  144 . 
     In some embodiments, the charging device may charge battery modules using electrical power received from an electric grid. Referring to  FIG. 1 , input connection  132  electronically couples charging device  102  to AC supply  110 . As used herein, electronically couple may refer to any electronically conductive connection. In the example, charging device  102  converts the AC power received from the AC supply  110  to charge battery module  106  and/or battery module  104 . In some embodiments, the charging device may discharge battery modules onto an electric grid, as described further below. In other embodiments, the charging device may discharge one or more battery cells of a battery module to charge one or more other battery cells of the battery module or one or more battery cells of another battery module (not shown). 
     In some embodiments, the charging device may maintain a charge level (e.g., charge and/or discharge) of a battery module using a bulk output. Referring to  FIG. 1 , bulk output  130  may electronically couple series section  124  of charging device  102  to one or more battery cells of battery module  106 . In some embodiments, the charging device may maintain a charge level (e.g., charge and/or discharge) of a battery module using an equalization connector. Referring to  FIG. 1 , equalization output  128  may electronically couple parallel section  122  of charging device  102  to one or more battery cells of battery module  104 . 
     In some embodiments the parallel section of a charging device may include a first converter for charging battery cells in parallel. Referring to  FIG. 2 , first converter  222  may receive power from an AC system associated with AC supply  110  (see  FIG. 1 ). For example, first converter  222  may support various voltages, currents, power levels, frequencies (e.g., 50 Hz, 60 Hz), number of phases, and the like. In the example, first converter  222  may support a 480/600 volt AC voltage. In some instances, a transformer (not shown) may be used to adjust an input voltage to account for regional differences. For example, a first transformer is used for a 480/600 volt AC voltage for input into first converter  222  and a second transformer is used for a 347/600 volt AC voltage for input into first converter  222 . As such, first converter  222  may support various AC voltages without impacting conversion between the AC and DC systems. 
     Similarly, the first converter may support various DC systems. For example, first converter  222  may support a DC system associated with one or more battery cells of battery module  104  and/or one or more battery cells of battery module  106 . In some embodiments, first converter  222  may output a voltage (e.g., operating voltage, nominal voltage, etc.) of a battery cell. For example, each battery cell of battery module  104  may have a nominal voltage of 3.3 volts. In the example, first converter  222  may output 3.3 volts at equalization output  128 . In other examples, first converter  222  may output other voltages. 
     The first converter may use various types of converter topologies including, for example, buck, boost, buck-boost, and the like. Similarly, the first converter may use various types of inverter topologies including, for example, a grid-tie inverter system, a square wave, modified square wave, modified sine wave, pure sine wave, and the like. The topologies used in the first converter may support a bi-directional function. As used herein, a bi-directional DC/AC converter may include a converter configured to (1) convert from the DC system to the AC system and (2) convert from the AC system to the DC system. In some embodiments, the first converter may include an AC to DC converter for converting from the AC system to the DC system and a DC to AC inverter for converting from the DC system to the AC system. In other embodiments, a single converter is used to convert between the AC and the DC systems. 
     In some embodiments the series section of a charging device may include a second converter for charging battery cells in series. Referring to  FIG. 2 , series section  124  may include second converter  224 . In some embodiments, second converter  224  is substantially similar to first converter  222  except that the first converter and second converter  224  output different voltages. In some embodiments, first converter  222  may output a charge voltage (e.g., operating voltage, nominal voltage, etc.) of a battery cell of a battery module (e.g.,  104 ) and second converter  224  may output a charge voltage (e.g., operating voltage, nominal voltage, etc.) of series string of battery cells of a battery module (e.g.,  104 ). For example, each of the twelve battery cells of battery module  104  may be connected in series and each of the twelve battery cells of battery module  104  may have a nominal voltage of 3.3 volts, thereby resulting in battery module  104  having a nominal voltage of about 40 volts. In the example, first converter  222  may output 3.3 volts at equalization output  128  while second converter may output 40 volts at bulk output  130 . 
     In those instances where the first converter and/or the second converter utilize a switching topology, any suitable switching control may be used to facilitate a selection of voltages output on the bulk output and/or equalization output. In some embodiments, controller  120  may selectively switch the first converter of the parallel section and/or the second converter of the series section to suitable voltage levels. For example, controller  120  may be programmed by a human user to switch first converter  222  to output a first voltage on equalization output  128  and to switch second converter  224  to output a second voltage on bulk output  130 . In the example, the first voltage (e.g., 3.3 volts) may be less than the second voltage (e.g., 39.6 volts). 
     In some embodiments, the series section may include a discharge circuit. In some embodiments, the discharge circuit may include a resistive element, such as a fixed or variable resistor (e.g., wire wound, grid resistor, etc.), and a switch, such as a transistor (metal-oxide-semiconductor field-effect transistor, bipolar junction transistor, insulated-gate bipolar transistor, etc.). Referring to  FIG. 2 , discharge circuit  226  may include resistive element  240  and switch  242 . In some embodiments, the discharge circuit may selectively switch two or more resistors to permit different discharge rates (not shown). In some embodiments, switch  242  is periodically closed and opened to permit different discharge rates. Referring to  FIG. 2 , controller  120  may selectively open and close switch  242  using pulse width modulation. For example, a duty cycle (e.g., proportion of a time closed) of switch  242  may be increased to permit a faster discharge rate or may be decreased to permit a slower discharge rate. 
     In some embodiments, the charging device may selectively switch between the discharge circuit and the second converter. In some embodiments, the controller may selectively switch between the charging and discharging states using a switch (e.g., transistor, electromagnetic relay, etc.). As shown in  FIG. 2 , switch  202  may be a single pole change over switch configured for electronically coupling bulk output  130  to either second converter  224  or discharge circuit  226 . In other embodiments, other types of switches (e.g., double pole change over) may be used. 
     In some embodiments, the charging device may simultaneously have an equalization output electronically coupled to a first battery module and a bulk output electronically coupled to a second battery module. Referring to  FIG. 3 , charging device  102  may be electronically coupled to battery module  104  by equalization output  128  and rig  108 . As used herein, a rig may refer to a lid having a set of buses for connecting battery cells of a battery module in parallel, as discussed further with respect to  FIGS. 10-16 . In the example, first connector  320  (e.g., positive polarity) and second connector  322  (e.g., negative polarity) of equalization output  128  of charging device  102  may be electronically coupled to first connector  324  and second connector  326  of rig  108  for battery module  104 . Similarly, first connector  330  (e.g., positive polarity) and second connector  332  (e.g., negative polarity) of bulk output  130  of charging device  102  may be electronically coupled to first terminal  302  and second terminal  304  of battery module  106 . In other embodiments, the charging device may have an equalization output electronically coupled to a first battery module and a bulk output electronically uncoupled or disconnected. Referring to  FIG. 4 , charging device  102  may be electronically coupled to battery module  104  by equalization output  128  and rig  108 . In the example bulk output  130  may be electronically isolated from battery module  104  and battery module  106 . 
     In some embodiments, the charging device may be portable to permit use in remote locations. In some embodiments, the charging station may be disposed in close proximity with a battery module. Referring to  FIGS. 5-6 , charging device  102  may be stacked onto battery module  106 . In the example, battery module  104  may be placed adjacent to battery module  106 , for example, to reduce a footprint of the battery module system. In other embodiments, the charging station may be spaced apart from a battery module. Referring to  FIG. 7 , charging device  102  may be spaced apart from battery modules  104  and  106 . In the example, battery module  104  may be electronically coupled to equalization output  128  using rig  108  and battery module  106  may be electronically coupled to bulk output  130 . In other examples, battery module  104  may be electronically decoupled from equalization output  128  (not shown) or battery module  106  may be electronically decoupled from bulk output  130  (not shown). 
     In some embodiments, a panel of a battery module may be removed from an enclosure of the battery module to permit attachment of a rig. Referring to  FIG. 8 , battery module  800  may be substantially similar to battery module  104  and battery module  106 . For example, battery module  800  may include twelve battery cells connected in series to a first terminal  802  and a second terminal  804 . As shown in  FIGS. 8 and 9 , removal of panel  806  from enclosure  808  may expose cavity  902  of enclosure  808 . 
     In some embodiments, a set of bus bars electronically couple battery cells of a battery module in series with terminals of the battery module to permit discharging and charging of the battery cells. Referring to  FIG. 9 , battery module  800  may have set of battery cells  911  that includes battery cells  912 - 934 . In the example, set of battery cells  911  may be electronically coupled by set if bus bars  939 . In other examples, set of battery cells  911  may include different numbers of battery cells. In the example, set of bus bars  939  may include bus bars  940 - 964 . In the example, bus bar  940  connects an anode of battery cell  912  to a cathode of battery cell  914 , bus bar  942  connects an anode of battery cell  914  to a cathode of battery cell  916 , bus bar  944  connects an anode of battery cell  916  to a cathode of battery cell  918 , bus bar  946  connects an anode of battery cell  918  to a cathode of battery cell  920 , bus bar  948  connects an anode of battery cell  920  to a cathode of battery cell  922 , bus bar  950  connects an anode of battery cell  922  to a cathode of battery cell  924 , bus bar  952  connects an anode of battery cell  924  to a cathode of battery cell  926 , bus bar  954  connects an anode of battery cell  926  to a cathode of battery cell  928 , bus bar  956  connects an anode of battery cell  928  to a cathode of battery cell  930 , bus bar  958  connects an anode of battery cell  930  to a cathode of battery cell  932 , and bus bar  960  connects an anode of battery cell  932  to a cathode of battery cell  934 . In the example, bus bar  962  may electronically couple a cathode of battery cell  912  to first terminal  802  and bus bar  964  may electronically couple an anode of battery cell  934  to second terminal  804 . 
     In some embodiments, a battery module system may include a rig for equalizing a battery cell charge of battery cells disposed in a battery module. Some embodiments may include any suitable number of hand screws to attach the rig to an enclosure of a battery module. Referring to  FIG. 10 , rig  108  may include hand screws  1010 - 1016  to permit a human user to secure rig  108  onto a battery module (e.g.,  104 ,  800 , etc.). In some embodiments, hand screws are disposed on top surface  1008  of lid  1006 . In the example, top surface  1008  of lid  1006  may include first connector  324  (e.g., positive polarity) and second connector  326  (e.g., negative polarity) of rig  108  for connection with first connector  320  (e.g., positive polarity) and second connector  322  (e.g., negative polarity) of equalization output  128 . 
     In some embodiments, the rig may include a set of buses for electronically coupling with battery cells of a battery module. As used herein, a bus may be formed of any material suitable for conducting electrical current, for example, copper, aluminum, and the like. Referring to  FIG. 11 , rig  108  may include first bus  1116  and second bus  1118 . It should be understood that although  FIG. 11  depicts first bus  1116  as associated with a positive ‘+’ polarity and depicts second bus  1118  as associated with a negative ‘−’ polarity, the polarity associated with the set of buses may be different. For example, first bus  1116  may be associated with a negative ‘−’ polarity and second bus  1118  may be associated with a positive ‘+’ polarity (not shown). 
     In some embodiments, bus bars of the rig may be insulated by one or more insulation layers. As used herein, an insulation layer may be formed of any dielectric material suitable for resisting a flow of electrical current, for example, fiberglass, porcelain, plastics, parylene, and the like. Referring to  FIG. 11 , insulating layer  1112  may be disposed between first bus  1116  and second bus  1118 . In the example, insulating layer  1110  may be disposed on one side of first bus  1116  and insulating layer  1112  may be disposed on the other side of first bus  1116 . Similar, in the example, insulating layer  1114  may be disposed on one side of second bus  1118  and insulating layer  1112  may be disposed on the other side of second bus  1118 . 
     In some embodiments, the rig may include an edging to permit the lid of the rig to seal a cavity of a battery module. Referring to  FIG. 11 , rig  108  may include edging  1102  that attaches to the lid  1006 . In the example, rig  108  may be disposed onto a battery module by a human user to seal a battery module (see  FIG. 16 ), thereby preventing dust and dirt from entering into the battery module. 
     In some embodiments, the set of busses of the rig may include contact elements to electronically couple to battery cells of a battery module. Referring to  FIG. 12 , first bus  1116  may include contact element  1281  for a cathode of a first battery cell (e.g.,  912 ), contact element  1283  for a cathode of a second battery cell (e.g.,  914 ), and contact element  1285  for a cathode of a third battery cell (e.g.,  916 ). As shown, contact element  1281  of first bus  1116  may be representative of other contact elements of first bus  1116 . For example, contact element  1281  may have a shape, thickness, material, and the like of contact elements  1283  and  1285 , as well as other contact elements of first bus  1116 . It should be understood that the first bus may include any suitable number of contact elements. In some embodiments, first bus  1116  may include a contact element for each battery cell of a battery module. 
     Similarly, second bus  1118  may include contact element  1280  for an anode of a first battery cell (e.g.,  912 ), contact element  1282  for an anode of a second battery cell (e.g.,  914 ), and contact element  1284  for an anode of a third battery cell (e.g.,  916 ). As shown, contact element  1280  of second bus  1118  may be representative of other contact elements of second bus  1118 . For example, contact element  1280  may have a shape, thickness, material, and the like of contact elements  1282  and  1284 , as well as other contact elements of second bus  1118 . It should be understood that the second bus may include any suitable number of contact elements. In some embodiments, second bus  1118  may include a contact element for each battery cell of a battery module. 
     In some embodiments, an elongated portion of the first bus and/or the second bus may extend along a first axis. Referring to  FIG. 12 , elongated portion  1216  of first bus  1116  and elongated portion  1218  of second bus  1118  extend in one or more directions parallel to first axis  1202 . In some embodiments, contact elements of the first bus and/or the second bus may extend in one or more directions parallel to second axis  1204 . In the example, first axis  1202  and second axis  1204  are perpendicular. Referring to  FIG. 12 , contact element  1281  of first bus  1116  may extend away from elongated portion  1216  of first bus  1116  in a direction parallel to second axis  1204 . Similarly, in the example, contact element  1282  of second bus  1118  may extend away from elongated portion  1218  of second bus  1118  in a direction parallel to second axis  1204 . As shown, in some embodiments, contact elements of the first bus and/or the second bus may extend in different directions along the second axis. Referring to  FIG. 12 , contact element  1281  of first bus  1116  extends along one direction of second axis  1204  (e.g., left) while contact element  1283  of first bus  1116  extends along the other direction of second axis  1204  (e.g., right). Similarly, contact element  1280  of second bus  1118  extends along one direction of second axis  1204  (e.g., right) while contact element  1282  of second bus  1118  extends along the other direction of second axis  1204  (e.g., left). 
     In some embodiments, the buses of the rig may be stacked. Referring to  FIG. 12 , first bus  1116  and second bus  1118  are stacked in a direction along third axis  1206 , which may be perpendicular to first axis  1202  and second axis  1204 . In some embodiments, the buses are stacked with insulating layers. Referring to  FIG. 12 , first bus  1116 , second bus  1118 , and insulating layers  1110 - 114  are stacked along third axis  1206 . 
     In some embodiments, contact elements of a bus of the rig are interwoven with contact elements of another bus of the rig to permit a coupling of battery cells disposed in a battery module to have alternating cathode and anode connections to facilitate a series connection. Referring to  FIG. 12 , contact element  1282  of second bus  1118  is disposed between contact elements  1281  and  1285  of first bus  1116 . Similarly, contact element  1283  of first bus  1116  is disposed between contact elements  1280  and  1284  of second bus  1118 . 
     In some embodiments, anodes and cathodes of battery cells of a battery module may be alternating to facilitate electronically coupling the battery cells in series. Referring to  FIG. 13 , first anode  1380  of battery cell  912  is spaced closer to second cathode  1383  of battery cell  914  than second anode  1382  of battery cell  914 . In the example, first cathode  1381  of battery cell  912  is spaced closer to second anode  1382  of battery cell  914  than second cathode  1383  of battery cell  914 . Similarly, as shown in  FIG. 13 , second anode  1382  of battery cell  914  is spaced closer to third cathode  1385  of battery cell  916  than third anode  1384  of battery cell  916 . In the example, second cathode  1383  of battery cell  914  is spaced closer to third anode  1384  of battery cell  916  than third cathode  1385 . 
     In some embodiments, battery cells of a battery module may be aligned in the battery module to facilitate electrical coupling of the battery cells. In some embodiments, a cathode of a first battery, an anode of a second battery, and a cathode of a third battery are aligned. Referring to  FIG. 13 , first anode  1380  of battery cell  912 , second cathode  1383  of battery cell  914 , and third anode  1384  of battery cell  916  are aligned along first axis  1202 . In the example, first cathode  1381  of battery cell  912 , second anode  1382  of battery cell  914 , and third cathode  1385  of battery cell  916  are aligned along first axis  1202 . In some embodiments, a cathode and an anode of a battery cell are aligned. Referring to  FIG. 13 , first anode  1380  of battery cell  912  and first cathode  1381  are aligned along second axis  1204 . In the example, second anode  1382  of battery cell  914  and second cathode  1383  are aligned along second axis  1204 . In the example, third anode  1384  of battery cell  916  and third cathode  1385  are aligned along second axis  1204 . 
     In some embodiments, contact elements of a rig may extend away from a bottom surface of a lid of a rig. Referring to  FIG. 13 , contact elements  1280 - 1285  may extend away from bottom surface  1308  of lid  1006  of rig  108 . In some embodiments, contact elements of a rig may extend away from a bottom surface of a lid of a rig and towards battery cells of a battery module. Referring to  FIGS. 14 and 15 , contact element  1281  may extend towards battery cell  912 . In the example, other contact elements may extend towards battery cell  912  (not shown) and/or other towards other battery cells (not shown). 
     In some embodiments the rig may be attached to the battery module. In some embodiments, a human user may attach the rig to an enclosure of a battery module. Referring to  FIG. 14 , rig  108  may be attached to enclosure  808 . In some embodiments, one or more fasteners may be used to attach and/or secure the rig to the battery module. Referring to  FIG. 14 , a human user may thread hand screws  1010 - 1016  into enclosure  808 . In some embodiments, threading the hand screws may force the rig downward into a cavity of the enclosure of a battery module such that a contact element of the rig may electronically couple with battery cells of a battery module. In other embodiments, the fasteners may be a bolt (not shown), pin, clamp, and the like. Referring to  FIGS. 14-16 , threading of hand screws  1010 - 1016  may move rig  108  into cavity  902  (see  FIG. 9 ) of enclosure  808 . In the example, such a threading moves contact element  1281  into direct contact with first cathode  1381  of battery cell  912 . 
     In some instances the battery module may be in a series configuration to facilitate bulk maintenance (e.g., charging and/or discharging) of battery cells of the battery module. Referring to  FIG. 17 , in the series configuration shown, set of bus bars  939  (e.g., bus bars  940 - 964  of  FIG. 9 ) electronically couple set of battery cells  911  (e.g., battery cells  912 - 934  of  FIG. 9 ) in series with bulk output  130 . In the example, charging device  102  outputs a second voltage (e.g., 40 volts) to bulk output  130  to change a charge level of set of battery cells  911 . In other embodiments, the battery module may be in a parallel configuration (see  FIGS. 21-22 ). 
     In some embodiments, charging device  102  may selectively switch between a charging state and a discharging state. In some embodiments, the controller may selectively switch between the charging and discharging states using a switch (e.g., transistor, electromagnetic relay, etc.). As shown in  FIG. 17 , switch  202  may be a single pole change over switch. In other embodiments, other types of switches (e.g., double pole change over) may be used. In the example, in the series configuration of the battery module, controller  120  may cause switch  202  to electronically couple discharge circuit  226  to the bulk output  130  for bulk discharging one or more battery cells of set of battery cells  911 . Alternatively, in the series configuration of the battery module, controller  120  may cause switch  202  electronically couple converter  224  to the bulk output  130  for bulk charging one or more of set of battery cells  911  (see  FIGS. 19-20 ). 
     In some embodiments, in the discharging state, a charge level of one or more battery cells of a battery module may be reduced. Referring to  FIG. 17 , set of battery cells  911  of battery module  800  may have initial combined charge level  1730  of about seventy-five percent of a maximum charge level of battery module  800 , battery cell  916  may have initial charge level  1720  of about fifty percent of a maximum charge level of battery cell  916 , and battery cell  924  may have initial charge level  1710  of about one-hundred percent of a maximum charge level of battery cell  924 . In the example, as shown in  FIG. 18 , discharge circuit  226  may discharge set of battery cells  911  such that battery module  800  may have charge level  1830  of about fifty percent of a maximum charge level of battery cell  912 , battery cell  916  may have charge level  1820  of about twenty percent of a maximum charge level of battery cell  916 , and battery cell  924  may have charge level  1810  of about seventy-five percent a maximum charge level of battery cell  924 . It should be understood that, in some embodiments, in the discharging state, the charging device may transfer energy from the battery module to an electric grid connection to permit line regeneration. For example, charging device  102  may transfer energy from battery module  800  to AC supply  110  (see  FIG. 1 ) using a bi-direction ac-dc converter (e.g.,  224 ). 
     In some embodiments, in the charging state, a charge level of one or more battery cells of a battery module may be increased. Referring to  FIG. 19 , set battery cells  911  of battery module  800  may have initial combined charge level  1930  of about seventy-five percent of a maximum charge level of battery module  800 , battery cell  916  may have initial charge level  1920  of about fifty percent of a maximum charge level of battery cell  916 , and battery cell  924  may have initial charge level  1910  of about one-hundred percent of a maximum charge level of battery cell  924 . In the example, as shown in  FIG. 20 , second converter  224  of charging device  102  may charge set of battery cells  911  such that battery module  800  may have combined charge level  2030  of about one-hundred percent of a maximum charge level of battery module  800 , battery cell  916  may have charge level  2020  of about seventy-five percent of a maximum charge level of battery cell  916 , and battery cell  924  may have charge level  2010  of about one-hundred-twenty-five (e.g., overcharged) percent a maximum charge level of battery cell  924 . 
     In some instances the battery module may be in a parallel configuration to facilitate equalization of battery cells of the battery module. Referring to  FIG. 21 , in the parallel configuration shown, rig  108  may electronically couple set of battery cells  911  in parallel with equalization output  128 . In the example, charging device  102  outputs a second voltage (e.g., 3.3 volts) to equalization output  128  to change a charge level of set of battery cells  911 . In other embodiments, the battery module may be in a series configuration (see  FIGS. 17-20 ). 
     In some embodiments, in the parallel configuration, a charge level of one or more battery cells of a battery module may be increased. Referring to  FIG. 21 , set of battery cells  911  of battery module  800  may have initial combined charge level  2130  of about seventy-five percent of a maximum charge level of battery module  800 , battery cell  916  may have initial charge level  2120  of about fifty percent of a maximum charge level of battery cell  916 , and battery cell  924  may have initial charge level  2110  of about one-hundred percent of a maximum charge level of battery cell  924 . In the example, as shown in  FIG. 22 , first converter  222  of charging device  102  may charge set of battery cells  911  such that battery module  800  may have combined charge level  2230  of about one-hundred percent of a maximum charge level of battery module  800 , battery cell  916  may have charge level  2220  of about one-hundred percent of a maximum charge level of battery cell  916 , and battery cell  924  may have charge level  2210  of about one-hundred percent a maximum charge level of battery cell  924 . That is, the equalization output and rig may be used to equalize or balance charge levels of battery cells of a battery module to reduce overcharging of battery cells and/or to improve an amount of energy stored in a battery module. 
     It should be understood that, in some embodiments, a charge rate in the parallel configuration may be different than a charge rate in the parallel configuration. For example, charging device  102  may charge battery module  800  in the parallel configuration (see  FIGS. 21-22 ) using a faster charge rate than battery module  800  in the series configuration (see  FIGS. 17-20 ). Further, in some embodiments, a charging device may measure (e.g., using a sensor circuit) and record the different charging rates to detect electrical characteristics of the battery module and/or one or more battery cells of the battery module. For example, local terminal  126  may record such charging rates in data store  150  (see  FIG. 1 ) and/or transmit such charging rates to remote data store  140  using one or more networks  144  (see  FIG. 1 ). 
     While various embodiments of the invention have been described, the description is intended to be exemplary, rather than limiting and it will be apparent to those of ordinary skill in the art that many more embodiments and implementations are possible that are within the scope of the invention. Accordingly, the invention is not to be restricted except in light of the attached claims and their equivalents. Also, various modifications and changes may be made within the scope of the attached claims.