Patent Publication Number: US-2022224139-A1

Title: Distributed battery management system for electric vehicle

Description:
CROSS REFERENCE TO RELATED APPLICATION AND CLAIM OF PRIORITY 
     The present application claims priority to U.S. Provisional Patent Application No. 63/135,452 filed on Jan. 8, 2021, the entire contents of which are hereby incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The disclosure relates generally to electric vehicles, and more particularly to battery management systems of electric vehicles. 
     BACKGROUND 
     Electric vehicles can include a battery pack having a plurality of battery modules that are each connected to a central battery management system (BMS). The BMS receives sensed parameters from the battery modules and uses the sensed parameters as inputs to control the operation of the battery pack. For example, the BMS is responsible for making sure the battery is operating within its safe operating conditions, for monitoring the battery&#39;s state of charge (SoC) and state of health (SoH), and for balancing the operation of the battery cells within each battery module, among other functions. To promote safe and efficient control of the battery pack, it is important that the BMS receives reliable sensed parameters from the battery modules. 
     SUMMARY 
     In one aspect, the disclosure describes a battery module comprising:
         a plurality of battery cells; and   an integrated battery module controller, the integrated battery module controller comprising an analog-to-digital converter and at least one connector for connecting to tabs of the plurality of battery cells, wherein a distance between the analog-to-digital converter and the at least one connector is between 20-100 mm,   wherein the integrated battery module controller is in signal communication with a master battery management controller located remotely from the battery module.       

     The battery module may further comprise a grouping of battery cell tabs, the grouping comprising battery cell tabs of at least two battery cells of the plurality of battery cells, wherein the at least one connector connects to the grouping of battery cell tabs. 
     The distance between the analog-to-digital converter and the at least one connector may be between 35-60 mm. 
     The distance between the analog-to-digital converter and the at least one connector may be between 40-50 mm. 
     The plurality of battery cells may comprise greater than 4 battery cells. 
     The plurality of battery cells may comprise 12 battery cells. 
     The at least one connector may comprise 7 connectors. The distance between the analog-to-digital converter and each of the 7 connectors may be between 20-100 mm. 
     The battery module may comprise a thermistor. A distance between the analog-to-digital converter and the thermistor may be less than 100 mm. 
     The plurality of battery cells may be a plurality of battery pouch cells. 
     The integrated battery module controller may be coupled to a face of the battery module. 
     Embodiments may include combinations of the above features. 
     In another aspect, the disclosure describes an electric vehicle comprising:
         two battery modules each comprising a plurality of battery cells;   a modular distributed battery management system comprising:   a central battery management controller located remotely from the two battery modules; and   two integrated battery module controllers, each coupled to a respective one the two battery modules;   wherein each integrated battery module controller comprises an analog-to-digital converter and at least one connector for connecting to tabs of the plurality of battery cells of its respective battery module; and   wherein a distance between the analog-to-digital converter and the at least one connector is between 20-100 mm.       

     The two integrated battery module controllers may be daisy chained together. 
     In some embodiments, each battery module may comprise a prismatic enclosure containing its respective plurality of battery cells. 
     The battery modules may be arranged in a stack. 
     Embodiments may include combinations of the above features. 
     In another aspect, the disclosure describes a distributed battery management system for a multi-module traction battery pack of an electric vehicle. The distributed battery management system comprises:
         an analog-to-digital converter (ADC) integrated into a battery module of the traction battery pack of the electric vehicle, the ADC converting an analog signal indicative of a sensed voltage associated with one or more cells of the battery module into a digital signal indicative of the sensed voltage; and   a master controller that performs a function associated with the traction battery pack of the electric vehicle based on the sensed voltage, the master controller being external to the battery module and in digital data communication with the ADC to receive the digital signal indicative of the sensed voltage from the ADC.       

     The battery module may be a first battery module. The ADC may be part of a first module controller integrated into the first battery module. The distributed battery management system may include a second module controller integrated into a second battery module of the traction battery pack of the electric vehicle. The first module controller and the second module controller may be connected together in a daisy chain manner. 
     The master controller may be in digital data communication with both the first module controller and the second module controller via a controller area network (CAN) bus. 
     The distributed battery management system may comprise a printed circuit board on which the ADC is installed. The printed circuit board may define an electric conductor establishing electric communication from the ADC to a voltage sensing location associated with the one or more cells of the battery module. A length of the electric conductor may be less than or equal to 100 mm. 
     The one or more cells of the battery module may include a plurality of cells of the battery module. The ADC may be electrically connected to a plurality of voltage sensing locations associated with the plurality of cells of the battery module. The ADC may convert a plurality of analog signals indicative of respective sensed voltages at the plurality of voltage sensing locations into digital signals indicative of the respective sensed voltages. 
     Embodiments may include combinations of the above features. 
     In another aspect, the disclosure describes an electric powersport vehicle comprising a distributed battery management system as disclosed herein. 
     In another aspect, the disclosure describes a line-replaceable battery module of a multi-module traction battery pack of an electric vehicle. The line-replaceable battery module comprises:
         one or more battery cells;   a module controller converting an analog signal indicative of a sensed voltage associated with the one or more battery cells of the line-replaceable battery module into a digital signal indicative of the sensed voltage; and   a digital communication interface for communicating the digital signal indicative of the sensed voltage externally of the line-replaceable battery module.       

     The line-replaceable battery module may comprise a cover covering tabs associated with the one or more battery cells. The cover may also cover the module controller. 
     The line-replaceable battery module may comprise a printed circuit board on which the module controller is installed. The printed circuit board may define an electric conductor establishing electric communication from the module controller to a voltage sensing location associated with the one or more cells of the battery module. A length of the electric conductor may be less than or equal to 100 mm. 
     The one or more battery cells may include six or more battery cells. 
     The line-replaceable battery module may comprise a printed circuit board on which the module controller is installed. The printed circuit board may define electric conductors establishing electric communication from the module controller to voltage sensing locations associated with the six or more cells of the line-replaceable battery module. A length of each electric conductor may be less than or equal to 100 mm. 
     Embodiments may include combinations of the above features. 
     In another aspect, the disclosure describes a method of performing a function associated with an operation of a traction battery pack of an electric vehicle. The method comprises:
         at the battery module: generating an analog signal indicative of a sensed voltage associated with the one or more battery cells; and converting the analog signal into a digital signal indicative of the sensed voltage;   communicating the digital signal indicative of the sensed voltage to a master controller external to the battery module; and   using the master controller to perform the function associated with the operation of the traction battery pack based on the sensed voltage.       

     The method may comprise converting the analog signal into the digital signal at a distance of less than or equal to 100 mm from a voltage sensing location used to generate the analog signal. 
     The analog signal may be a first analog signal indicative of a first sensed voltage associated with a first of the one or more battery cells. The digital signal may be a first digital signal indicative of the first sensed voltage. The method may include, at the battery module:
         generating a second analog signal indicative of a second sensed voltage associated with a second of the one or more battery cells;   converting the first analog signal into the first digital signal at a first distance of less than or equal to 100 mm from a first voltage sensing location used to generate the first analog signal; and   converting the second analog signal into a second digital signal indicative of the second sensed voltage at a second distance of less than or equal to 100 mm from a second voltage sensing location used to generate the second analog signal.       

     The method may comprise:
         communicating the second digital signal indicative of the second sensed voltage to the master controller; and   using the master controller, performing the function associated with the operation of the traction battery pack based on the first sensed voltage and the second sensed voltage.       

     Embodiments may include combinations of the above features. 
     Further details of these and other aspects of the subject matter of this application will be apparent from the detailed description included below and the drawings. 
    
    
     
       DESCRIPTION OF THE DRAWINGS 
       Reference is now made to the accompanying drawings, in which: 
         FIG. 1  is a schematic representation of an exemplary electric vehicle including a battery management system as described herein; 
         FIG. 2  is an exemplary schematic representation of the battery management system of the vehicle of  FIG. 1 ; 
         FIG. 3  is a schematic representation of an exemplary topology of a battery module of a battery pack of the vehicle of  FIG. 1 ; 
         FIG. 4  is a perspective view of an exemplary multi-cell battery module of the battery pack of the vehicle of  FIG. 1 ; 
         FIG. 5  is a perspective view of part of the multi-cell battery module of  FIG. 4  with a cover thereof being removed; 
         FIG. 6  is a top plan view of the multi-cell battery module of  FIG. 4  with the cover removed; 
         FIG. 7  is a schematic top plan view of the multi-cell battery module of  FIG. 4 ; 
         FIG. 8  is a perspective view of an exemplary battery pack including a plurality of multi-cell battery modules of  FIG. 4 ; and 
         FIG. 9  is a flowchart of a method of monitoring a voltage of a battery cell of a battery module of an electric vehicle. 
     
    
    
     DETAILED DESCRIPTION 
     The following disclosure describes battery management systems (BMSs) and associated components and methods for electric vehicles. In some embodiments, the systems and methods described herein may be particularly suitable for electric powersport vehicles. Examples of suitable electric powersport vehicles include snowmobiles, motorcycles, watercraft such as boats and personal watercraft (PWCs), all-terrain vehicles (ATVs), and (e.g., side-by-side) utility task vehicles (UTVs). In some embodiments, the systems and methods described herein may facilitate the control and operation of a traction battery pack by promoting a high reliability and accuracy of sensed parameters (e.g., voltage(s) and temperature(s)) associated with cells of battery modules of such traction battery packs. In some embodiments, the systems and methods described herein may promote reduced wiring between battery modules and a master battery management controller for the traction battery pack. 
     In electric vehicles implementing a centralized BMS, where each battery module of a battery pack is associated with a small module controller located on a printed circuit board (PCB) at a central battery management controller located remotely of the battery modules, the module controller obtains analog readings of voltage and temperature for one or more battery cells within the battery module. Each battery module may be connected via several wires to this small controller resulting in a relatively large number of wires that run relatively long distances from each battery module to its respective module controller at the central battery management controller. A failure of any part (e.g., a module controller or connector) located at the central battery management controller PCB may require replacement and reconnection of the entire PCB. In addition, replacement of a battery module may require rewiring of the battery module to the central battery management controller. Further, transmitting analog signals over longer electric conductors can increase the risk of signal loss (e.g., voltage drop) and/or signal noise affecting the accuracy of the analog signals. 
     In contrast with a centralized BMS, a distributed BMS as described herein may include a module controller associated and integrated with each battery module, and in digital data communication with a master battery management controller that controls an operation of the battery pack based on one or more sensed parameters (e.g., voltage, temperature) that are communicated from the module controller(s) to the master battery management controller in digital form. In some embodiments, a single module controller may be configured to perform analog-to-digital conversions of one or more parameters associated with the battery cells of its battery module. A suitable data bus may be used to communicate the sensed parameters from one or from a plurality of module controllers to the master battery management controller. Accordingly, the architecture of the distributed BMS described herein may, in some embodiments, promote reduced cost, reduced wiring, reduced part count, and/or reduced complexity. In some embodiments, the distributed BMS may improve the modularity of the battery pack, as battery modules may be more easily connected to, and disconnected from, the distributed BMS as compared to a centralized BMS. Also, the proximity of the module controllers to the tabs or to other (e.g., voltage, temperature) sensing locations of the battery cells may also promote accuracy and reliability of the sensed voltages and/or of other sensed parameters. This in turn may promote efficient control of the battery pack by reducing the risk of signal loss and/or signal noise that may be otherwise associated with analog signals that are transmitted over longer electric conductors. 
     The term “connected” and “coupled” may include both direct connection and coupling (in which two elements contact each other) and indirect connection and coupling (in which at least one additional element is located between the two elements). The term “connected” also includes electrical connections. 
     The term “substantially” as used herein may be applied to modify any quantitative representation which could permissibly vary without resulting in a change in the basic function to which it is related. 
     Aspects of various embodiments are described through reference to the drawings. 
       FIG. 1  is a schematic representation of an exemplary electric powersport vehicle  10  (referred hereinafter as “vehicle  10 ”) including battery management system  12  (referred hereinafter as “BMS  12 ”) as described herein. As illustrated in  FIG. 1 , vehicle  10  may be a snowmobile but it is understood that the systems described herein may also be used on other types of electric vehicles such as electric UTVs, electric ATVs, electric PWCs, electric motorcycles, boats having electric outboard motors, and other electric powersport vehicles. In some embodiments, vehicle  10  may be an electric snowmobile including elements of the snow vehicle described in International Patent Publication No. WO 2019/049109 A1 (Title: BATTERY ARRANGEMENT FOR ELECTRIC SNOW VEHICLES), and U.S. Patent Application No. 63/135,497 (Title: ELECTRIC VEHICLE WITH BATTERY PACK AS STRUCTURAL ELEMENT) which are incorporated herein by reference. 
     Vehicle  10  may include a frame (also known as a chassis) which may include tunnel  14 , track  16  having the form of an endless belt for engaging the ground and disposed (i.e., located) under tunnel  14 , one or more electric motors  18  (referred hereinafter in the singular) mounted to the frame and configured to drive track  16 , left and right skis  20  disposed in a front portion of vehicle  10 , straddle seat  22  disposed above tunnel  14  for accommodating an operator of vehicle  10  and optionally one or more passengers (not shown). Skis  20  may be movably attached to the frame to permit steering of vehicle  10  via a steering assembly including a steering column interconnecting handlebar  24  with skis  20 . 
     Motor  18  may be drivingly coupled to track  16  via a drive shaft. Electric motor  18  may be in torque-transmitting engagement with the drive shaft via a belt/pulley drive. However, motor  18  may be in torque-transmitting engagement with the drive shaft via other arrangements such as a chain/sprocket drive, or shaft/gear drive for example. The drive shaft may be drivingly coupled to track  16  via one or more toothed wheels or other means so as to transfer motive power from motor  18  to track  16 . 
     In various embodiments, motor  18  may be a permanent magnet synchronous motor or a brushless direct current motor for example. In some embodiments, motor  18  may have a power output rating of between 120 and 180 horsepower, or motor  18  may have a maximum output power rating of greater than 180 horsepower, for example. Motor  18  may be of a same type as, or may include elements of, the motors described in U.S. Provisional Patent Application No. U.S. 63/135,466 (Title: DRIVE UNIT FOR ELECTRIC VEHICLE) and U.S. Provisional Patent Application no. U.S. 63/135,474 (Title: DRIVE UNIT WITH FLUID PATHWAYS FOR ELECTRIC VEHICLE), which are both incorporated herein by reference. In some embodiments, multiple motors may be implemented to drive vehicle  10 . 
     Vehicle  10  may also include one or more brakes that may be applied or released by an actuation of a suitable brake actuator (e.g., lever) by the operator for example. In various embodiments, the brake(s) may include a friction-type brake including a master cylinder hydraulically connected to a brake caliper that forces brake pads against a brake rotor or disk that is coupled to a powertrain of vehicle  10 . Actuation of the brake actuator (e.g. lever) may cause a combination of friction braking and regenerative braking. Regenerative braking may also be applied in isolation, i.e., without friction braking. In some embodiments, regenerative braking may be used such that battery pack(s)  26  (referred hereinafter in the singular) of vehicle  10  is supplied with electric energy generated by motor  18  operating as a generator when the brake actuator is applied, and/or when the operator releases accelerator  28 . 
     Battery pack  26  may provide electric power to motor  18  for driving motor  18  when vehicle  10  is being propelled by motor  18 . Battery pack  26  may be a main battery pack used for propelling vehicle  10 . In other words, battery pack  26  may also be referred to as a “motoring” or “traction” battery pack. Battery pack  26  may be located under seat  22 . In some embodiments, battery pack  26  may be a rechargeable multi-module, multi-cell lithium ion battery pack as explained further below. The battery cells of battery pack  26  may be pouch cells, cylindrical cells and/or prismatic cells, for example. Battery pack  26  may include a battery enclosure to house the battery modules and/or battery cells for protection from impacts, water and/or debris. In some embodiments, battery pack  26  may be configured to output electric power at a voltage of between 300-400 volts, or up to 800 volts, for example. 
     The operation of motor  18  and the delivery of electric power to motor  18  from battery pack  26  may be controlled by one or more vehicle controllers  30  based on an actuation of accelerator  28 , also referred to as “throttle”, by the operator. The delivery of electric power to motor  18  may be controlled via a suitable power electronics module, such as a power inverter (not shown), including electronic switches (e.g., insulated gate bipolar transistor(s)) to provide motor  18  with electric power having the desired voltage, current, waveform, etc. to implement the desired performance of vehicle  10 . Vehicle controller(s)  30  may include one or more electronic control units (ECUs), or one or more electronic control modules (ECMs) in some embodiments. An example of an ECU or ECM is a motor controller, which may be or include a power inverter. Vehicle controller(s)  30  may include a computer including one or more data processors and non-transitory machine-readable memory storing instructions for execution by the one or more data processors. Vehicle controller(s)  30  may control, based on sensed and/or operator inputs, various aspects of vehicle  10 . 
     Vehicle controller(s)  30  may include master battery management controller  32  (referred hereinafter as “master controller  32 ”), which may be part of BMS  12 . Master controller  32  may be integrated with a control system of vehicle  10 , as shown in  FIG. 2  as being part of vehicle controller(s)  30 . Alternatively, master controller  32  may be part of a standalone BMS  12  that is separate from a control system of vehicle  10 . Vehicle controller(s)  30  may operate and communicate with one or more other systems  42  (shown in  FIG. 2 ) of vehicle  10 . For example, vehicle controller(s)  30  may be in communication with and optionally perform control functions associated with a steering system, motor  18 , power management, and thermal management of vehicle  10  for example. 
     Master controller  32  may include a computer including one or more data processors and non-transitory machine-readable memory storing instructions for execution by the one or more data processors. Master controller  32  may also or instead include an application specific integrated circuit (ASIC) and/or a field programmable gate array (FPGA). Through the use of master controller  32  and one or more module controller(s) described below, BMS  12  may perform various monitoring and control functions associated with the operation of battery pack  26 . BMS  12  may include any suitable electronic system that manages battery pack  26  or part(s) thereof. Examples of functions performed by BMS  12  may include protecting battery pack  26  from operating outside its safe operating zone (e.g., over current protection and monitoring the state of battery pack  26 ), calculating and reporting data (e.g., voltage, state of charge) associated with battery pack  26 , controlling the environment in which battery pack  26  operates, authenticating battery pack  26 , and/or balancing battery pack  26 . BMS  12  may monitor the state of battery pack  26  as represented by parameters such as total voltage of battery pack  26 , voltages of individual cells or groups of cells, average temperature, coolant intake temperature, coolant output temperature, temperatures of individual cells, coolant flow in embodiments where battery pack  26  is liquid-cooled or air-cooled, and/or current flowing in or out of battery pack  26  for example. BMS  12  may perform one or more control functions associated with battery pack  26  by the control/actuation of one or more switches to control a flow of electric current, and/or one or more valves to control a flow of coolant fluid. In some embodiments, BMS  12  may control a heater (not shown) to warm battery pack  26  when it is below a defined operating temperature. The heater may be implemented within a thermal management system to warm a coolant fluid. 
       FIG. 2  is a schematic representation of an exemplary distributed BMS  12  of vehicle  10 . BMS  12  may include battery module controllers  34 A- 34 N (referred generically herein as “module controllers  34 ”) each associated and integrated with a respective battery module  36 A- 36 N (referred generically herein as “battery modules  36 ”) of battery pack  26 . Battery modules  36  may be located within a common battery pack  26 . Battery pack  26  may be operatively connected to supply electric power to motor  18  and optionally one or more other electric loads within vehicle  10 . Battery pack  26  may include two or more battery modules  36 . In some embodiments, battery pack  26  may include fourteen or more battery modules  36 . In some embodiments, battery pack  26  may include sixteen battery modules  36 . In some embodiments, battery modules  36  may be electrically daisy chained together in series for delivering electric power to motor  18 , and optionally to other electric loads of vehicle  10 . 
     In some embodiments, each module controller  34  may be operative to obtain sensed parameters such as voltage and temperature readings associated with one or more battery cells within its associated battery module  36 . Each module controller  34  may be operatively connected to one or more sensors  38 A- 38 N (e.g., thermistor(s), thermocouple(s), electric conductors, connectors and connections for voltage sensing), for the acquisition of one or more sensed parameters. In embodiments where a battery module  36  includes more than one temperature sensor, the readings from the multiple temperature sensors may be averaged at module controller  34  and the average temperature associated with the applicable battery module  36  may be communicated to master controller  32 . Voltage readings may be acquired by, for example, electric conductors extending from module controller  34  to tabs of battery module  36  or to other voltage sensing locations as explained below. 
     Each integrated module controller  34  may be in digital data communication with master controller  32  via wireless or wired connections. In some embodiments, module controllers  34  may each be in digital data communication with master controller  32  via data bus  40 . In various embodiments, data bus  40  may be a Controller Area Network (CAN) bus, or a suitable serial peripheral interface such as coupling circuitry known under the trade name isoSPI™ for example. Module controllers  34  may function as intermediaries that feed digital data indicative of sensed parameters to master controller  32 . Module controllers  34  may also receive instructions from master controller  32  and, for example, cause the discharge of individual battery cells when instructed by master controller  32 . In some embodiments, module controllers  34  may not execute control logic for controlling the operation of their respective battery modules  36 . Module controllers  34  may each have built-in analog-to-digital converter (ADC) capabilities. Alternatively, battery modules  36  may each have an ADC that is external to and in data communication with module controllers  34 . Module controllers  34  may each include or be a microcontroller such as a CAN controller that may store bits of data received from data bus  40  and also transmit bits serially onto data bus  40  when data bus  40  is free. 
     Master controller  32  may be integrated with battery pack  26  or may be disposed externally of battery pack  26 . Master controller  32  may execute control and/or monitoring functions of BMS  12 . For example, master controller  32  may aggregate the data received as digital signals from module controllers  34 , and execute logic to control one or more operations associated with battery pack  26  such as directing the charging of battery cells, directing the discharging of battery cells, and/or directing other functions associated with battery pack  26 . For example, temperature readings of cells or groups of cells may be used to control a cooling system delivering a cooling fluid to battery modules  36 . 
     BMS  12  may have a distributed architecture where some (e.g., data acquisition and analog-to-digital conversion) functions may be performed locally at individual battery modules  36  using module controllers  34 , and other (e.g., battery management and control) functions may be performed remotely of individual battery modules  36  using master controller  32 . BMS  12  and battery pack  26  may each have a modular construction. 
       FIG. 3  is a schematic representation of an exemplary topology of battery module  36  of battery pack  26  of vehicle  10 . Various embodiments of battery module  36  may include one or more battery cells  44 A- 44 L (referred generically herein as “cells  44 ”). In some embodiments, battery module  36  may include two or more cells  44 . In some embodiments, battery module  36  may include six or more cells  44 . In some embodiments, battery module  36  may include twelve or more cells  44 . 
     In the embodiment of  FIG. 3 , battery module  36  includes six pairs of cells  44  (i.e., a first pair including cells  44 A and  44 B, a second pair including cells  44 C and  44 D, a third pair including cells  44 E and  44 F, a fourth pair including cells  44 G and  44 H, a fifth pair including cells  441  and  44 J, and a sixth pair including cells  44 K and  44 L) that are connected in series (i.e., daisy chained together). Both cells  44  in each pair of cells  44  are connected in parallel. Battery module  36  may have other topologies in other embodiments. In total, battery module  36  may, for example, include 12 cells  44 , outputting twice the current and six times the voltage of a single cell  44 . 
     Battery module  36  may include electric conductors  46 A- 46 G (referred generically herein as “electric conductors  46 ”) extending between module controller  34  and suitable parameter sensing locations  48 A- 48 G (referred generically herein as “sensing locations  48 ”) for measuring voltages and/or temperatures associated with cells  44 . Electric conductors  46 A- 46 F may serve as parameter sensing lines. In embodiments where sensing locations  48  are voltage sensing locations, electric conductors  46  may each include (e.g., copper) wires and/or tracks/traces on a printed circuit board. Sensing locations  48  may include tabs (i.e., positive and negative connections) of individual cells  44  or groups of cells  44 . Alternatively, sensing locations  48  may include intermediate connectors in electric communication with tabs of cells  44  or of groups of cells  44  of battery module  36  to permit voltage sensing. Groupings of tabs of cells  44  may be configured to correspond to the lowest voltage point (e.g., sensing location  48 A) of battery module  36 , the highest voltage point (e.g., sensing location  48 G) of battery module  36 , and each point (e.g., sensing locations  48 G- 48 F) in between the pairs of cells  44  connected in series for a total of seven sensing locations  48 . 
     Electric conductors  46  may establish electric communication between module controller  34  and sensing locations  48  via soldered connections, riveted connections, welded connections, crimped connections, connectors, or other suitable electric connections. Electric conductors  46 A and  46 B may be used to measure a voltage across the pair of cells  44 A and  44 B that are electrically connected in parallel. Similarly, electric conductors  46 B and  46 C may be used to measure a voltage across the pair of cells  44 C and  44 D that are electrically connected in parallel. Electric conductors  46  may be used to measure voltages across other pairs of cells  44  that are electrically connected in parallel in a similar manner. 
     In some embodiments, distance D between module controller  34  and sensing locations  48  may be relatively short to promote short lengths of individual electric conductors  46 . The short lengths of electric conductors  46  may in turn promote measurement accuracy by reducing signal loss and reducing the risk of noise. In some embodiments, the lengths of individual electric conductors  46  may be substantially the same and within a desired tolerance that provides similar signal losses between electric conductors  46 . In some embodiments, the lengths of individual electric conductors  46  may differ but still be within a predetermined range that provides an acceptable level of signal loss or risk of noise. In other words, the lengths of electric conductors  46  may not be uniform across all electric conductors  46 . The lengths of electric conductors  46  may be a factor that influences signal loss (e.g., conductor impedance). Other factors that may influence signal loss may include the material type and the cross-sectional area of electric conductors  46  for example. 
     Distance D may represent a physical (e.g., 2-dimensional or 3-dimensional) straight line distance between module controller  34  and respective sensing locations  48 . Distance D may also represent a path length of electric conductor(s)  46  establishing electric communication between module controller  34  and respective sensing locations  48 . In various embodiments, distance D for any, one, some or all of sensing locations  48  may be less than or equal to 100 mm. For example, 100 mm may represent a threshold that, below which, the signal loss and/or noise associated with electric conductor(s)  46  is within an acceptable range to provide reliable and accurate measurements. In some embodiments, distance D for any, one, some or all of sensing locations  48  may be between 20 mm and 100 mm. In some embodiments, distance D for any, one, some or all of sensing locations  48  may be between 35 mm and 60 mm. In some embodiments, distance D for any, one, some or all of sensing locations  48  may be between 40 mm and 50 mm. Narrowing the range of values for distance D may reduce the variation in signal loss and noise associated with different sensing locations  48 . In reference to  FIG. 3 , the seven electric conductors  46  may each have a length that is less than or equal to 100 mm. In some embodiments, the seven sensing locations  48  may each be at a straight line distance from module controller  34  that is less than or equal to 100 mm. 
     Battery module  36  may include one or more connectors  50 A,  50 B connecting module controller  34  to data bus  40 . In the embodiment of  FIG. 3 , ADC  51  is shown to be incorporated in module controller  34 . Since the one or more sensed voltages may be converted from analog signals to digital signals, data communication between module controller  34  and master controller  32  may be established using only two wires irrespective of the number of sensed parameters that are communicated from module controller  34  to master controller  32 . Accordingly, connectors  50 A,  50 B may each be two-wire connectors. In some embodiments, connectors  50 A,  50 B may be replaced with a single two-wire connector that taps into the two wires of data bus  40 . For example, battery modules  36  may be connected to data bus  40  in parallel. The use of connectors  50 A,  50 B may permit a plurality of module controllers  34  of battery modules  36  to be daisy chained together in series along data bus  40 , or connected together in any other suitable fashion. The use of connectors  50 A,  50 B may also facilitate the modular configuration of BMS  12  where, if one battery module  36  is determined to be faulty, the faulty battery module  36  may be easily replaced (i.e., switched out) by disconnecting the faulty battery module  36  from data bus  40  via connectors  50 A,  50 B, and connecting an operational (e.g., new) battery module  36  to data bus  40  via the same connectors  50 A,  50 B in a plug-and-play manner. In other words, connectors  50 A,  50 B may define a digital communication interface between data bus  40  and module controller  34 . 
     In some embodiments, the digital signals transmitted on data bus  40  may be more resilient to noise and loss as compared to analog signals. Therefore, battery modules  36  may be spaced apart from master controller  32  while still communicating accurate and reliable sensor data. This may allow battery modules  36  to be positioned within vehicle  10  without restrictions due to signal loss and/or noise. Space and weight are at a premium in electric vehicles, and in particular in electric powersports vehicles. Enabling the size and weight associated with battery modules  36  to be distributed within vehicle  10  without restrictions due to signal loss and/or noise may provide design improvements. For example, battery modules  36  may be positioned within vehicle  10  to improve space efficiency and/or to obtain an improved center of mass. Further, the daisy chain configuration of data bus  40  may enable multiple smaller battery modules  36  (e.g., more than four battery modules  36 ) to be implemented without increasing the number of wires connected to master controller  32 . Smaller battery modules  36  may be more easily placed in available space within vehicle  10  to achieve a smaller overall profile of vehicle  10 . 
       FIG. 4  is a perspective view of an exemplary multi-cell battery module  36  of battery pack  26  of vehicle  10 . In some embodiments, cells  44  may be battery cells contained in a prismatic (e.g., rectangular) enclosure or housing. The prismatic enclosure may enable battery modules  36  to be stacked or otherwise arranged in a space efficient manner. In some embodiments, cells  44  may be pouch battery cells. In some embodiments, cells  44  may be lithium ion battery cells but it is understood that aspects of the present disclosure are also applicable to other types of battery cells. In some embodiments, battery module  36  may have cooling panels integrated therein for fluid communication with a source of cooling fluid. For example, battery modules  36  may have cooling panels and cells  44  as disclosed in U.S. Patent Publication No. 2021/0135307 A1 (Title: BATTERY COOLING PANEL FOR ELECTRIC VEHICLES), which is incorporated herein by reference. 
     Battery module  36  may include positive terminal  52 A and negative terminal  52 B which may be used to electrically connect battery module  36  to other battery modules  36  and/or to electric loads of vehicle  10 . Battery module  36  may include removable cover  54  defining part of a housing of battery modules  36 . Cover  54  may be covering module controller  34  and optionally other components of battery module  36 . Connectors  50 A,  50 B may be accessible via one or more apertures formed in cover  54 . 
     Battery module  36  may be configured as a modular line-replaceable unit or component that is designed to be replaced as a unit relatively easily and quickly in order to restore an operational condition of battery pack  26 . For example, in the event of a malfunction of battery module  36  such as a malfunction of one or more cells  44  or a malfunction of module controller  34 , the malfunctioning battery module  36  may be replaced relatively easily through the use of connectors  50 A,  50 B as explained above, without having to replace other functioning battery modules  36  or other components of battery pack  26 , or of BMS  12 . 
       FIG. 5  is a perspective view of an upper portion of battery module  36  shown in  FIG. 4  with removable cover  54  thereof removed. Removal of removable cover  54  may expose module controller  34  and tabs  58 . Module controller  34  may be disposed on PCB  56 , which may be integrated in battery module  36  by being fastened to a structural component (e.g., enclosure, casing, frame) of battery module  36 . 
       FIG. 6  is a top plan view of battery module  36  of  FIG. 4  with removable cover  54  being removed from battery module  36 .  FIG. 6  shows a plan view of front face  57  of battery module  36 .  FIG. 6  schematically shows module controller  34  being connected to data bus  40  in a daisy chain manner via connectors  50 A,  50 B. In some embodiments, module controllers  34  could be configured to instead be connected in parallel via connectors  50 A,  50 B. Module controller  34  may be located on and coupled to a (e.g., front or other) face  57  of battery module  36 . For example, module controller  34  may be physically implemented as one or more chips and/or other electronic devices on PCB  56  that is mounted (e.g., attached, fastened and/or soldered) to a same side of battery module  36  as tabs  58  (blades) associated with cells  44  of battery module  36 . Module controller  34  may be implemented as a microcontroller having a built-in ADC  51 . Alternatively, ADC  51  may be implemented separately of module controller  34 . Module controller  34  and/or ADC  51  may be located toward a middle (i.e., central region) of PCB  56  and also relatively centrally of sensing locations  48 . 
     In reference to  FIG. 6 , sensing locations  48 A- 48 D may correspond to voltage sensing locations, and sensing location  48 T may correspond to a temperature sensing location. For example, sensing location  48 T may be the location of a thermistor that is electrically connected to module controller  34  via electric conductor(s)  46 T. The thermistor may be disposed between battery cells  44  of battery module  36 . As illustrated, distance D 1  is a straight-line distance between sensing location  48 T and module controller  34 . Distance D 2  is a straight-line distance between sensing location  48 B and module controller  34 . Distances D 1 , D 2  may instead represent the respective lengths of electrical conductors  46 T,  46 B. In some embodiments, distances D 1  and D 2  shown in  FIG. 6  may be less than or equal to 100 mm. In some embodiments, distances D 1  and D 2  may be between 35 mm and 60 mm. In some embodiments, distances D 1  and D 2  may be between 40 mm and 50 mm. In some embodiments, module controller  34  may be in communication with four or more cells  44  via electric conductors  46 . In some embodiments, module controller  34  may be in communication with six to twelve cells  44  via electric conductors  46 . 
     As shown in  FIG. 6 , some sensing locations  48  may correspond to locations of intermediate connectors in electric communication with tabs  58  of individual cells  44  and/or with tabs  58  associated with groups of cells  44  of battery module  36 . Each grouping of tabs  58  may include a combination of tabs  58  from more than one cell  44 . Battery module  36  may include any number of groupings of tabs  58 , and ADC  51  of module controller  34  may be in communication with any number of groupings of tabs  58 . 
     In order to attach module controller  34 , which may have been previously integrated with PCB  56 , to face  57  of battery module  36 , groupings of tabs  58  may be first electrically connected together via one or more metallic strips known as “V-sense” connectors that may be welded or soldered to applicable tabs  58  to provide suitable sensing locations  48 . Sensing locations  48  may correspond to electric connectors that provide electric communication between electric conductors  46  and tabs  58 . Such electric connectors may be soldered to the V-sense connectors to physically attach PCB  56  containing module controller  34  to battery module  36 . Module controller  34  with integrated ADC  51  may be electrically connected to a plurality of tabs  58  in this manner. Battery module  36  may include seven groupings of tabs  58 , and as such, module controller  34  may be in electric communication with tabs  58  via seven electric connections at different sensing locations  48 . By way of example, referring to  FIG. 3 , a grouping of tabs  58  corresponding to sensing location  48 A may include tabs from battery cells  44 A,  44 B, a grouping of tabs  58  corresponding to sensing location  48 B may include tabs from battery cells  44 A,  44 B,  44 C,  44 D, and so on. Only four voltage sensing locations  48 A- 48 D are identified in  FIG. 6  for clarity. In some embodiments, one soldered connection per V-sense connector and electric connector combination is possible at sensing locations  48 . In some embodiments, it may be desirable to have two or more soldered connections per V-sense connector and electric connector combination at sensing locations  48  for increased reliability. 
     When connecting module controller  34  to battery module  36  without damaging circuitry of PCB  56 , negative terminal  52 B of battery module  36  may first be grounded. This may be done by connecting conductive element  60  (e.g., wire, solder or other suitable electrical conductor) between negative terminal  52 B (e.g., the lower left grouping of tabs  58 ) and ground G. Ground G may be a bolt on front face  57  of battery module  36 , among other possibilities. Once negative terminal  52 B is grounded, electric connections may be made at sensing locations  48  by, for example, soldering the electric connectors to the V-sense connectors, and soldering the V-sense connectors to appropriate tabs  58 . Alternatively, to avoid connecting negative terminal  52 B to ground G prior to installation of module controller  34 , one or more mechanical fuses (e.g., socket) connectors  62  may be installed on PCB  56 . In this manner, there will not be any electric connection between tabs  58  and circuitry of PCB  56  until mechanical fuses are added to PCB  56  via mechanical fuse connectors  62  when ready. 
       FIG. 7  is a schematic top plan view of multi-cell battery module  36  of  FIG. 4  that shows seven voltage sensing locations  48 A- 48 H configured in a similar manner as shown in  FIG. 3  except for the lengths of electric conductors  46  being non-uniform. While electric conductors  46  are shown as straight lines in  FIG. 7 , it should be noted that one or more electric conductors  46  may instead include bends or curves.  FIG. 7  shows a plan view of front face  57  of battery module  36 .  FIG. 7  also shows one temperature sensing location  48 T but battery module  36  may include a plurality of temperature sensing locations, which may correspond to a plurality of temperature sensors disposed at different locations within battery module  36 . Sensing locations  48  may be disposed at different distances (e.g., D 3  and D 4 ) from ADC  51  where such distances may be less than or equal to 100 mm as explained above. Module controller  34  may be mounted to PCB  56  and electric conductors  46  may each include tracks/traces on PCB  56 . In some embodiments, sensing locations  48  may be defined on PCB  56 . Accordingly, the distances between ADC  51  and sensing locations  48  may be within a boundary of PCB  56 , which is integrated into battery module  36 . 
     ADC  51  may convert analog signals indicative of sensed voltages at sensing locations  48  and associated with one or more cells  44  into digital signals indicative of the sensed voltages. Module controller  34  may then communicate the digital signals remotely to master controller  32  via data bus  40 . 
     As shown in  FIG. 7 , ADC  51  may be positioned substantially centrally on face  57  of battery module  36  and/or substantially centrally of the plurality of sensing locations  48 . In some embodiments, ADC  51  is positioned substantially centrally on PCB  56 . 
       FIG. 8  is a perspective view of an exemplary battery pack  26  including a plurality of multi-cell battery modules  36  of  FIG. 4  with their covers  54  removed. Battery modules  36  may be arranged in multiple stacks. In some embodiments, battery pack  26  may include eight battery modules  36  daisy chained together along data bus  40 . Master controller  32  may be disposed external to (i.e., remotely) of battery pack  26  and still be in digital data communication with individual battery modules  36  via data bus  40 . Battery modules  36  may also be electrically daisy chained together via bus bars  64  electrically connecting positive terminals  52 A and negative terminals  52 B of adjacent battery modules  36  together to electrically connect battery modules  36  in series. 
       FIG. 9  is a flowchart of a method  100  of performing a function associated with an operation of a traction battery pack of an electric vehicle. Method  100  may be performed using BMS  12  or another BMS. Aspects of method  100  may be combined with other actions described herein. Aspects of BMS  12  and vehicles described herein may be incorporated into method  100 . In various embodiments, method  100  may include:
         at battery module  36 : generating an analog signal indicative of a sensed voltage associated with the one or more battery cells  44  (block  102 ); and converting the analog signal into a digital signal indicative of the sensed voltage (block  104 );   communicating the digital signal indicative of the sensed voltage to master controller  32  external to battery module  36  (block  106 ); and   using master controller  32  to perform the function associated with the operation of the traction battery pack  26  based on the sensed voltage (block  108 ).       

     In some embodiments, method  100  may include converting the analog signal into the digital signal at a distance of less than or equal to 100 mm from voltage sensing location  48  used to generate the analog signal. 
     In some embodiments of method  100 , the analog signal may be a first analog signal indicative of a first sensed voltage associated with a first of the one or more battery cells  44 . The digital signal may be a first digital signal indicative of the first sensed voltage. Method  100  may include, at battery module  36 , generating a second analog signal indicative of a second sensed voltage associated with a second of the one or more battery cells  44 . Method  100  may include, at battery module  36 , converting the first analog signal into the first digital signal at a first distance of less than or equal to 100 mm from a first voltage sensing location  48 A used to generate the first analog signal. Method  100  may include, at battery module  36 , converting the second analog signal into a second digital signal indicative of the second sensed voltage at a second distance of less than or equal to 100 mm from a second voltage sensing location  48 B used to generate the second analog signal. 
     In some embodiments, method  100  may include communicating the second digital signal indicative of the second sensed voltage to master controller  32 . In some embodiments, method  100  may include, using master controller  32 , performing the function associated with the operation of traction battery pack  26  based on the first sensed voltage and the second sensed voltage. 
     The embodiments described in this document provide non-limiting examples of possible implementations of the present technology. Upon review of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made to the embodiments described herein without departing from the scope of the present technology.