WO2021220306A1

WO2021220306A1 - Wireless communication in a battery pack

Info

Publication number: WO2021220306A1
Application number: PCT/IN2021/050420
Authority: WO
Inventors: Chinnaraj HARIPRIYA; Arun K P; Dhinagar SAMRAJ JABEJ
Original assignee: Tvs Motor Company Limited
Priority date: 2020-04-30
Filing date: 2021-04-29
Publication date: 2021-11-04

Abstract

A battery pack (101) and a method for wireless exchange of battery information between a battery pack and a user device (112) are disclosed. A battery pack comprises cells (102) and a battery management system (BMS) (103) electrically coupled to the cells (102) for generating battery information. The BMS (103) comprises a master processor (104) and a remote monitoring device (107) for wirelessly communicating the battery information with a user device. The user device comprises a diagnostics application (113) for communicating with the remote monitoring device (107) of the BMS (103) of the battery pack. The diagnostics application(113) of the user device (112) provides one or more selection options on a user interface (114) of the diagnostics application (113) for generating and transmitting a pack history request, a connection request, an update request,and a scan request for wirelessly communicating the battery information with a user device (112).

Description

WIRELESS COMMUNICATION IN A BATTERY PACK

TECHNICAL FIELD

[0001] The present subject matter relates to an energy storage device. More particularly, wireless communication capabilities of an energy storage device are disclosed.

BACKGROUND

[0002] In recent years, rechargeable energy storage devices have been widely used as an energy source for a number of electronic and electrical units, hybrid and electric vehicles. Commonly used rechargeable energy storage devices include, for example, nickel cadmium batteries, nickel hydrogen batteries, nickel zinc batteries, and lithium rechargeable batteries. Lithium rechargeable energy storage devices are widely used in electric and hybrid vehicles because they are rechargeable, they can be made in a compact size with large capacity, they have a high operation voltage, and they have a high energy density per unit weight.

[0003] An existing energy storage device comprises one or more energy storage cells, such as, lithium ion battery cells enclosed within a casing. Multiple sensors are installed on the cells to measure health of the cells, such as, their temperatures, voltages, state of charge, etc. These parameters are critical for normal functioning of the energy storage for a long duration of time. The exothermic electrochemical reactions within the lithium ion battery cells are responsible for the increased temperatures of the lithium ion battery cells. The increased temperatures degrade the electrical performance of the energy storage device and may lead to catastrophic failure of the energy storage devices. Further, the state of charge of the cells, fault detection in the cells, if left undetected may result in disruption in the supply of voltage and current by the lithium ion battery cells, thereby causing discomfort to the user of the energy storage device.

[0004] There is a need to sense the critical parameters in the energy storage device, control the operation of the energy storage device by an electronic component of the energy storage device, and communicate health of the energy storage device to users for safe operation and longevity of the energy storage device. BRIEF DESCRIPTION OF DRAWINGS [0005] The detailed description is described with reference to the accompanying figures. The same numbers are used throughout the drawings to reference like features and components.

[0006] Fig. 1 exemplarily illustrates a schematic diagram showing an exchange of battery information between a battery pack and a user device;

[0007] Fig. 2 exemplarily illustrates a flowchart depicting a method for wireless exchange of the battery information between the battery pack and the user device; [0008] Figs. 3A-3B exemplarily illustrate a flowchart showing steps performed by the BMS for the exchange of the battery information between the BMS and the user device;

[0009] Figs. 4A-4B exemplarily illustrate a flowchart showing steps performed by the diagnostics application for the exchange of battery information between the BMS and the diagnostics application on the user device;

[0010] Fig. 5 exemplarily illustrates a schematic diagram for exchange of batter information between a user, for example a service engineer at a service station and the BMS;

[0011] Fig. 6 exemplarily illustrates a schematic diagram of exchange of battery information between the user device and the BMS for performing diagnosis of the battery pack at a service station;

[0012] Fig. 7 exemplarily illustrates a schematic diagram of exchange of battery information between the user device and the BMS for improving performance of the battery pack at a service station;

[0013] Fig. 8 exemplarily illustrates a schematic diagram of exchange of battery information between the user device and the BMS for performing diagnosis of the battery pack at a service station; and

[0014] Figs. 9A-9E exemplarily illustrate screenshots of the user interface of the diagnostics application in the user device. DETAILED DESCRIPTION OF THE INVENTION [0015] In existing energy storage devices, an electronic component, referred to as a battery management system (BMS), supervises the energy storage device. The BMS acts as an intermediate between the cells or sensors on the cells and the user. The BMS is connected to each of the cells or a cluster of cells and monitors and controls health of the cells. The BMS is aware of the state of the cells, the connections between the cells, output delivered from the battery, etc.

[0016] In high voltage applications, multiple energy storage devices, either connected in series and/or parallel combination, are used. To view the health of an energy storage device out of the lot of energy storage devices, separate communication accessories including a software are to be plugged onto the energy storage device. Further, the multiple energy storage devices communicate with each other and with an external charger using a communication network. In case of mismatch in the physical wiring used in the communication network, the communication of the critical parameters between the energy storage devices and the external charger will not occur.

[0017] Further, for diagnosis of problems in the energy storage devices or in the applications with the energy storage devices, historical data pertaining to the energy storage device, such cell parameters, faults, number of charging and discharging cycles, life of the energy storage device, rate of discharge of the energy storage device, etc., is very essential. The historical data may need a large storage space, hence would preferably be stored remotely. However, easy access to the historical data in the remote storage space must be provided for a service engineer trying to debug the problem with the energy storage device.

[0018] There is a need to provide wireless communication capability to the battery pack, specifically to the BMS of the energy storage device, to overcome the disadvantages of the physical communication media between the battery pack and the diagnostic tools. However, the wireless communication of the cell parameters may be susceptible to hacking, unauthorized access, theft, tampering and hamper the privacy of communication of cell parameters between the BMS and the user. Also, for the communication of the cell parameters, clear allocation of frequencies for communication is necessary. Further, the wireless technology adopted in communication between the BMS and the user need not limit the user, such as, the service engineer to use only specifically designed diagnostic couplers for diagnosis of the issues with the battery pack. If restricted to the specific diagnostic couplers that are faulty, there could be irregular acquisition of the cell parameters of the battery pack during diagnosis that results in improper diagnosis of the battery pack. [0019] Therefore, there exists a need for wireless communication of the cell parameters between the BMS and a user device for monitoring health, improving performance, and diagnosis of problems in the energy storage device, overcoming all problems disclosed above as well as other problems of known art.

[0020] The present subject matter discloses a battery pack with a wireless capability to communicate with a user device for continuous monitoring, diagnosis, and performance improvement of the battery pack. The battery pack comprises a plurality of cells defining total capacity of the battery pack and a battery management system (BMS) electrically coupled to the plurality of cells for generating battery information & managing the functioning of the battery unit. The BMS as per the present invention, comprises a master processor and a remote monitoring device for wirelessly communicating the battery information with a user device. In an embodiment, the remote monitoring device comprises at least one auxiliary processor and a wireless adapter for exchanging the battery information with the user device. In an embodiment, the user device comprises a diagnostics application for communicating with the remote monitoring device of the BMS of the battery pack. The master processor comprises a communication driver for communicating with the diagnostics application through the wireless adapter of the remote monitoring device. The master processor of the BMS processes cell parameters and generates the battery information and the remote monitoring device transmits the battery information to the diagnostics application of the user device. The remote monitoring device receives a connection request from the diagnostics application and the master processor establishes a connection between the remote monitoring device and the diagnostics application based on authentication of the connection request. The master processor updates firmware of the BMS using an update request remotely generated from the diagnostics application of the user device. The remote monitoring device continuously advertises or displays the battery information and the diagnostics application transmits a scan request to the remote monitoring device to receive the advertised battery information. The diagnostics application transmits a pack history request to the remote monitoring device and the diagnostics application receives processed battery information from the remote monitoring device corresponding to the transmitted pack history request. [0021] The diagnostics application of the user device provides one or more selection options on a user interface for generating and transmitting a pack history request, a connection request, an update request, and a scan request. The battery information comprises of at least one of state of charge of the plurality of cells, voltages of the plurality of cells, charging current of each of the plurality of cells, discharging current of each of the plurality of cells, temperature of each of the plurality of cells, and a unique identifier of the battery pack. In an embodiment, the master processor stores the battery information chronologically in a remote server periodically for analyzing the performance of the battery pack by the user. The master processor of the BMS activates the remote monitoring device, based on an activation flag. The master processor generates the activation flag based on one of a discharging condition of the battery pack and authentication of the diagnostics application in the user device by the master processor, based on a connection request received from the user device.

[0022] In another embodiment, a method for wireless exchange of battery information between the battery pack and the user device in implemented. The method comprises the steps of: generating the battery information by processing cell parameters received from the plurality of cells by the master processor of the BMS; activating the remote monitoring device by the master processor of the BMS based on an activation flag; advertising of the generated battery information by the activated remote monitoring device; transmitting the advertised battery information by the activated remote monitoring device to the user device based on a scan request from the diagnostics application; and storing the advertised battery information chronologically in a remote server periodically by the master processor for analyzing the performance of the battery pack. In an embodiment, the remote monitoring device advertises the battery information periodically. In an embodiment, the wireless adapter employs Bluetooth technology for exchanging the battery information with the user device.

[0023] In an embodiment, the master processor generates an activation flag based on one of a discharging condition of the battery pack and authentication of the diagnostics application on the user device by the master processor based on a connection request received from the user device. The method comprises performing a firmware update by the master processor of the BMS, based on receiving an update request from the user device. The master processor comprises a communication driver for communicating with the diagnostics application through the wireless adapter of the remote monitoring device. Generating the battery information by the master processor of the BMS comprises fault detection of the plurality of cells, thermal management of the plurality of cells, determine total energy delivered by the battery pack, total number of charging and discharging cycles, and total operating time of the battery pack, based on the cell parameters, and sequencing of data packets comprising the battery information to be transmitted to the diagnostics application. In an embodiment, the method comprises the step of transmitting a pack history request by the diagnostics application to the remote monitoring device and receiving processed battery information from the remote monitoring device corresponding to the transmitted pack history request by the diagnostics application.

[0024] Fig. 1 exemplarily illustrates a schematic diagram 100 showing an exchange of battery information between a battery pack 101 and a user device 112. As used herein, battery information refers to information pertaining to state of the battery pack 101. The battery pack 101 comprises multiple cells 102 housed within a casing. The cells 102 are arranged in a series and/or a parallel connection to deliver a determined voltage and current to electrical loads 115. The rated voltage or current of the battery pack 101 is defined by the connection of the cells 102 in the battery pack 101. In an embodiment, the cells 102 are rechargeable cells. The cells 102 discharge to deliver the desired power supply to the electrical loads 115 and the cells 102 are recharged by an external charger (not shown). The operations of the cells 102 is monitored and managed by a battery management system (BMS)

103. The BMS 103 is an electronic component of the battery pack 101 housed within the same casing. The BMS 103 is a printed circuit board with one or more integrated circuits integrally. The battery pack 101 has mounting provisions for mounting the BMS board 103. The BMS 103 is electrically coupled to the cells 102 in the battery pack 101 and protect the cells 102 from damage. The BMS 103 manages output, charging, discharging, capacity, cell balancing, etc., in the battery pack 101. As exemplarily illustrated, the BMS 103 comprises a master processor

104, a local memory unit 105, and a communication driver 106. In an embodiment, the communication driver 106 supports a Controller Area Network (CAN) interface. The BMS 103 communicates with the cells 102 using the CAN interface over a CAN bus within the battery pack 101.

[0025] Multiple sensors in the battery pack measure cell parameters, such as, voltage, current, internal temperature, state of charge of cells 102, impedance, ambient temperature, physical condition, such as, extent of corrosion, leakage of electrolyte, etc., of the cells 102 and communicate the measured cell parameters via the CAN bus to the master processor 104 of the BMS 103. The CAN bus is a wired connection between the cells 102 and the master processor 104 of the BMS 103. In an embodiment, the cells 102 and the master processor 104 may communicate wirelessly using a known communication means e.g. ZigBee^® of ZigBee Alliance Corporation.

[0026] The memory unit 105 of the BMS 103 locally stores/caches the cell parameters that the master processor 104 receives from the cells 103 (via sensors on the cells). The memory unit 105 may be a register memory, a processor cache, etc. The master processor 104, the memory unit 105, and the communication driver 106 are connected using transmission media such as wires that constitute a system bus coupled to the master processor 104. The master processor 104 processes the cell parameters and generates battery information. Using the cell parameters, the master processor performs fault detection of the cells 102, thermal management of the cells 102, determines total energy delivered by the battery pack 101, determines total number of charging and discharging cycles of the battery pack 101, and computes total operating time of the battery pack 101.

[0027] The battery information, thus comprises the state of charge of the cells 102, the voltage of the cells 102, the charging current and the discharging current of the cells 102, temperature of the cells 102, fault detection flags, thermal management flags, values for total energy delivered by the battery pack 101, total number of charging and discharging cycles of the battery pack 101, and the total operating time of the battery pack 101.

[0028] In addition to the master processor 104 and the memory unit 105, the BMS 103 comprises a remote monitoring device 107 that is capable of wirelessly communicating the battery information with the user device 112. In an embodiment, the remote monitoring device 107 comprises an auxiliary processor 108 and a wireless adapter 109. The wireless adapter 109 enables the remote monitoring device 107 to communicate with a wireless network 110. The remote monitoring device 107 communicates with the user device 112 via the wireless network 110. In an embodiment, the wireless network 110 is a mobile communication network, the Internet, a local area network (LAN), a wide area network (WAN) or the Ethernet, a token ring, or via any appropriate communications media, etc.

[0029] The wireless adapter 109 is an interface card provided in the remote monitoring device 107 at a marked location on the BMS 103. In an embodiment, the wireless adapter 109 is one or more of an infrared (IR) interface, an interface implementing Wi-Fi^® of Wi-Fi Alliance Corporation, an Ethernet interface, a digital subscriber line (DSF) interface, a token ring interface, a peripheral controller interconnect (PCI) interface, a local area network (FAN) interface, a wide area network (WAN) interface, interfaces using serial protocols, interfaces using parallel protocols, Ethernet communication interfaces, asynchronous transfer mode (ATM) interfaces, a high speed serial interface (HSSI), a fiber distributed data interface (FDDI), interfaces based on transmission control protocol (TCP)/intemet protocol (IP), interfaces based on wireless communications technology such as satellite technology, radio frequency (RF) technology, near field communication, a communication interface that implements ZigBee^® of ZigBee Alliance Corporation, an interface that supports general packet radio service (GPRS) network, a mobile telecommunication network interface such as a global system for mobile (GSM) communications network interface, a code division multiple access (CDMA) network interface, a third generation (3G) mobile communication network interface, a fourth generation (4G) mobile communication network interface, a fifth generation (5G) mobile communication network interface, a long term evolution (LTE) mobile communication network interface, etc. In a preferred embodiment, the wireless adapter 109 is an interface implementing Bluetooth^® of Bluetooth Sig, Inc. In an embodiment, the wireless adapter 109 controls input actions and output actions of interactions between the remote monitoring device 107 and the user device 112 and a remote server 111.

[0030] The master processor 104 communicates with the auxiliary processor 108 using the communication driver 106 via a communication interface, such as, a serial communication interface (SCI). The battery information generated by the master processor 104 is transmitted to the auxiliary processor 108 as a sequence of data packets over the SCI. The master processor 104 generates sequence of transmit data packets comprising the battery information. Each transmit data packet transmitted is a sequence of bits conveying the battery information along with the address of the sender and the address of the receiver of the transmit data packet. That is, the address of the sender is a unique identifier of the battery pack 101 stored in the memory unit 105 of the BMS 103 and the address of the receiver is, for example, the IP address of the user device 112, the IMEI number of the user device 112, etc. Thus, the transmit data packets comprise the bits encoded to represent the battery information, the identifier of the battery pack 101, and the address of the user device 112

[0031] The auxiliary processor 108 transmits the transmit data packets to the user device 112 via the wireless adapter 109. As exemplarily illustrated, the user device 112 comprises a diagnostics application 113 with a user interface 114. The diagnostics application 113 of the user device 112 receives the battery information from the wireless adapter 109 of the BMS 103. The user interface 114 of the diagnostics application 113 comprises text fields, checkboxes, text boxes, windows, etc., to interact with the received battery information. The user device 112 is, for example, a cellular phone, a smart phone, a tablet computing device, an Ultrabook^®· a laptop, a personal digital assistant, a touch centric device, etc., or any other mobile device configured for the wireless network. The diagnostics application 113 may be an Android based application, an iOS application, a Windows based application, etc. In an embodiment, the diagnostics application 113 is an application provided by an OEM of the BMS 103, that is available in the Application Store of the user device 112. The user interface 114 of the diagnostics application 113 comprises one or more selection options for generating and transmitting a pack history request, a connection request, an update request, and scan request. Based on the selected option from the user interface 114, the diagnostics application 113 generates response data packets that are transmitted to the remote monitoring device 107 via the network 110. The auxiliary processor 108 determines the action to be performed, as will be described in Figs. 2- 9E, based on the response data packets received from the user device 112. The master processor 104 and the auxiliary processor 108 are one or more microprocessors, central processing unit (CPU) devices, finite state machines, microcontrollers, digital signal processors, logic, a logic device, an user circuit, an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA), a chip, a digital circuit, an analog circuit, etc., or any combination thereof, capable of executing a series of commands, instructions, or state transitions. In an embodiment, the auxiliary processor 108 is embodied as a software module within the master processor 104. In an embodiment, the processing steps performed by the master processor 104 may also be performed by the auxiliary processor 108, in case of fault in the functioning of the master processor 104.

[0032] In an embodiment, the remote monitoring device, that is, the auxiliary processor and the wireless adapter are in sleep mode. The master processor 104 of the BMS 103 activates the remote monitoring device 107, based on an activation flag. The master processor 104 generates the activation flag based on a discharging condition of the battery pack 101 or authentication of the diagnostics application 113 in the user device 112 by the master processor 104, based on a connection request received from the user device 112. The discharging condition of the battery pack 101 is when an electrical connection is established between the battery pack 101 and the electrical loads 105 and the battery pack 101 discharges. The master processor 104 generates the activation flag when the battery pack 101 starts to discharge. In another embodiment, if a connection request as response data packets is received from the diagnostics application by the BMS 103 at the wireless adapter 109, the master processor 104 generates the activation flag to activate the wireless adapter 109 to accept the connection request and perform further actions.

[0033] As exemplarily illustrated, in addition to the user device 112, the remote monitoring device 107 communicates with a remote server 111 via the wireless network 110. The wireless adapter 109 of the remote monitoring device 107 transmits the generated transmit data packets to be stored in the remote server 111. The master processor 104 via the communication driver 106 and the wireless adapter 109 stores the battery information chronologically in a remote server 111 periodically, for example, daily, weekly, bi-weekly, monthly, etc. This stored information may later be used for analysis of the performance of the battery pack 101 by a user. The remote server 111 is a database server, for example, Microsoft^® SQL server, the Oracle^® server, or a Cloud storage, etc., that stores the transmit data packets that can be retrieved later on for diagnostics of the battery pack 101.

[0034] The user of the diagnostics application 113 can be the user of the battery pack 101 , a user of an application, such as, a vehicle employing such a battery pack 101, a service engineer of the battery pack 101, the OEM of the battery pack 101, etc. In an embodiment, the diagnostics application 113 on the user device 101 is used for diagnosis of issues in the battery pack 101 during servicing of the battery pack 101. The battery information stored in the remote server 111 constitutes history data of the battery pack 101. A user, for example, a service engineer, may retrieve the history data from the remote server 111 through the diagnostics application 113 and troubleshoot the aberrant behavior of the battery pack 101. The logged battery information also provides insights on the life, performance, and stability of the battery pack 101 for the OEMs of the battery pack 101. In an embodiment, the history battery information could be locally stored in the memory unit 105 of the BMS 103. The wireless adapter 109 may transmit the logged battery information from the memory unit 105 to the diagnostics application 113, on receiving a pack history request from the user device 112.

[0035] In an embodiment, the wireless adapter 109 of the remote monitoring device 107 transmits the transmit data packets in real time when requested by the diagnostics application 113. In another embodiment, the wireless adapter 109 advertises the battery information periodically and the diagnostics application 113 accesses the advertised battery information, when granted permission by the master processor 104. The transmit data packets and the response data packets are encrypted using encryption standards and may be decrypted with an authorization check only by the diagnostics application 113 and the auxiliary processor 108, respectively.

[0036] Fig. 2 exemplarily illustrates a flowchart 200 depicting a method for wireless exchange of the battery information between the battery pack 101 and the user device 112. As exemplarily illustrated, at step 201, the master processor 104 of the BMS 103 generates the battery information by processing the cell parameters received from the cells 102. In an embodiment, the master processor 104 receives the cell parameters from a cell monitoring device of the battery pack 101. The master processor 104 uses algorithms and functional models to generate the battery information from the cell parameters. Based on predefined threshold levels of the cell parameters, such as, voltage, current, etc., the faults in the functioning and the structure of the cells are identified and a fault detection flag is set. Similarly, the master processor 104 initiates thermal management as per the predefined threshold levels of temperatures of the cells 102 constituting the cell parameters. At 202, the remote monitoring device 107 is activated by the master processor 104, based on an activation flag. The activation flag is generated by the master processor 104 based on discharging condition of the battery pack 101 or based on authentication of the diagnostics application 113 on the user device 112. That is, if the battery pack 101 is connected to electrical loads 115, the battery pack 101 discharges and the discharging condition of the battery pack 101 is active. In case of the battery pack 101 employed in vehicles, when the vehicle ignition is turned ON, the battery pack 101 discharges to supply power to the electrical loads 115. Then, the master processor 104 generates the activation flag. In an embodiment, the remote monitoring device 107 may receive a connection request from the user interface 114 of the diagnostics application 113. The connection request allows the diagnostics application 113 to gain access to the battery information of the battery pack 101. The master processor 104 authenticates the diagnostics application 113 using an authentication algorithm, such as, a passkey, PIN, etc. If the activation flag is HIGH, the master processor 104 activates or wakes up the auxiliary processor 108 of the remote monitoring device 107 from SLEEP mode. In an embodiment, the activation flag may be turned ON manually by the user, such as, a service engineer accessing the battery pack 101.

[0037] At step 203, the wireless adapter 109 of the remote monitoring device 107 advertises the generated battery information. The battery information generated by the master processor 104 is transmitted to the auxiliary processor 108 by the communication driver 106 in form of transmit data packets in the encrypted form. The wireless adapter 109 advertises the encrypted transmit data packets. The diagnostics application 113 of the user device 112 determines the availability of the transmit data packets. If the user desires to access the battery information pertaining to the battery pack 101, the diagnostics application 113 transmits a scan request to the wireless adapter 109. At step 204, the auxiliary processor 108 transmits the advertised battery information to the diagnostics application 113, on receiving the scan request. If the diagnostics application 113 is already authenticated, the advertised battery information is directly transmitted to the diagnostics application 113. If in case the diagnostics application 113 is not authenticated, the master processor 104 authenticates the diagnostics application 113 to access the transmitted battery information, on receiving the scan request. The transmit data packets received on the user device 112 are decrypted by the authenticated diagnostics application 113 and the battery information retrieved is helpful in assessing and diagnosis of the condition of the battery pack 101. [0038] At step 205, the master processor 104 stores the advertised battery information chronologically in the remote server 111, through the wireless adapter 109 of the remote monitoring device 107. The method further comprises the step of performing a firmware update of the BMS 103 by the master processor 104, on receiving an update request from the user interface 114 of the diagnostics application 113. In another embodiment, the auxiliary processor 108 receives a pack history request from the diagnostics application 113. In correspondence to the pack history request, the auxiliary processor 108 fetches the battery information stored in the remote server 111 and transmits the battery information constituting the battery pack history to the diagnostics application 113 for analyzing the performance of the battery pack 101. The scan request, the connection, the update request, and the pack history request are transmitted as response data packets to the wireless adapter 109 of the remote monitoring device 107.

[0039] Figs. 3A-3B exemplarily illustrate a flowchart 300 showing steps performed by the BMS 103 for the exchange of the battery information between the BMS 103 and the user device 112. At step 301, the battery pack 101 is activated to turn ON the remote monitoring device 107 manually. At step 302, the master processor 104 of the BMS 103 determines if the advertising of the battery information by the wireless adapter 109 is ON. That is, master processor 104 determines if the flag for the pack advertising is high. If Yes, the auxiliary processor 108 checks for the inputs received from the user device 112, that is, the scan request, the connection request, the update request, and the pack history request from the diagnostics application 113. The auxiliary processor 108 transmits the requests received from the user to the master processor 104. At step 303, the auxiliary processor 108 determines if pack status request flag is HIGH. At step 304, the auxiliary processor 108 determines if only pack software update request flag is HIGH. At step 305, the auxiliary processor 108 determines if pack history request is HIGH. If the received input is a pack status request, that is a scan request, at step 306, the auxiliary processor 108 advertises the battery information with encryption in a predefined format for the diagnostics application 113 to access via the wireless adapter 109. If the received input from the user device 112 is an update request, at step 308, the auxiliary processor 108 communicates the software update request to the master processor 104. At step 309, the master processor 104 authenticates the connection between the BMS 103 and the user device 112. At step 310, the firmware of the BMS 103 is updated with the latest software. That is, the firmware of the master processor 104 is updated with a new software patch. The software patch is transmitted from the user interface 114 of the diagnostics application 113. Also, a confirmation is sent back to the user confirming a successful update of the firmware. If the received input is a pack history request, the auxiliary processor 108 transmits the pack history request to the master processor 104. The master processor 104 communicates with the remote server 111 to access the battery information of interest to the user and, at step 311, pushes the history battery information to the diagnostics application 113. If, at step 302, the master processor 104 of the BMS 103 determines that the advertising of the battery information by the wireless adapter is OFF, the master processor 104 switches the wireless adapter 109 to the advertising mode as shown in step 312. Subsequently, the Bluetooth capability of the user device 112 is turned OFF and the diagnostics application on the user device 113 is closed.

[0040] Figs. 4A-4B exemplarily illustrate a flowchart showing steps performed by the diagnostics application for the exchange of battery information between the BMS 103 and the diagnostics application 113 on the user device 112. At step 401, the Bluetooth capability of the user device 112 is turned ON and a SCAN option in the user interface 114 of the diagnostics application 113 is pressed. That is, a scan request is generated by the diagnostics application 113 and transmitted to the wireless adapter 109 of the remote monitoring device 107. At step 402, the master processor 104 of the BMS 103 determines if the advertising of the battery information by the wireless adapter 109 is ON. That is, master processor 104 determines if the flag for the pack advertising is high. If Yes, the auxiliary processor 108 checks for the inputs received from the user device 112, that is, the scan request, the connection request, the update request, and the pack history request from the diagnostics application 113. The auxiliary processor 108 transmits the requests received from the user device 112 to the master processor 104. At step 403, the auxiliary processor 108 determines that the pack status request flag is HIGH. At step 404, the auxiliary processor 108 determines if only pack software update request flag is HIGH. At step 405, the auxiliary processor 108 determines if pack history request is HIGH. If the received input is a pack status request, that is a scan request, the auxiliary processor 108 advertises the battery information with encryption in a predefined format for the diagnostics application 113 to access pack status via the wireless adapter 109. At step 406, the diagnostics application 113 decrypts the transmits data packets containing the battery information and the battery information is displayed in the user interface 114 of the diagnostics application 113. If only pack software update request flag is HIGH, the master processor 104 awaits diagnostics application 113 to transmit a connection request. At step 408, the master processor 104 authenticates the connection between the BMS 103 and the user device 112. Once the connection is established, the diagnostics application 113 transmits the software patch, when the update request in the user interface 114 is pressed at step 409. If pack history request is HIGH, the master processor 104 awaits a pack history request from the diagnostics application 113 of the user device 112. At step 407, the diagnostics application 113 transmits a pack history request and waits until the reception of file from the remote server 111. The master processor 104 communicates with the remote server 111 to access the battery information of interest to the user and pushes the history battery information to the diagnostics application 113. If, at step 402, the master processor 104 of the BMS 103 determines that the advertising of the battery information by the wireless adapter is OFF, the master processor 104 switches the wireless adapter 109 to the advertising mode as shown in step 410. Subsequently, the Bluetooth capability of the user device 112 is turned OFF and the diagnostics application on the user device 113 is closed.

[0041] Fig. 5 exemplarily illustrates a schematic diagram for exchange of battery information between a user, for example, a service engineer at a service station 501 and the BMS 103. At the service station 501, a user of the battery pack 101, that is a customer may approach with different requirements, such as, suspecting an issue with the battery pack 101 at step 502 or to improve the performance of the battery pack 101 in applications, such as, a vehicle at step 503. Corresponding to step 502, at step 504, the service engineer performs diagnosis of the battery pack 101 at the service station 501. Alternatively, at step 505, the diagnosis of the battery pack 101 is performed at the OEM end. Using the diagnostics application 113, the service engineer scans and views the battery information, at step 506, for diagnosing the problem in the battery pack 101 at the service station 501. If incase the diagnosis is performed at the OEM end, using the diagnostics application 113, the authorized personnel of the OEM connects with the BMS 103 using the connection request and request for the history battery information using the history request at step 507. The diagnostics application 113, at step 509, sends the received history battery information of the battery pack 101 to the authorized personnel. To improve the battery performance, the service engineer uses the diagnostics application 113 and connects with the BMS 103 using the connection request and updates the BMS software at step 508. At step 510, the service engineer fetches the required software patch from a cloud through the user interface 114 of the diagnostics application 113 and transmits the new software patch to the BMS 103.

[0042] Fig. 6 exemplarily illustrates a schematic diagram of exchange of battery information between the user device 112 and the BMS 103 for performing diagnosis of the battery pack 101 at a service station. At the service station, the discharging condition of the battery pack 101 is established. That is, the battery pack 101 is connected to discharge to the electrical loads 115. If incase, the battery pack 101 is used in a vehicle, on turning on the ignition switch of the vehicle, the battery pack 101 tends to discharge to supply the electrical loads 115, such as, lamps, horn, in the vehicle. At step 601, the ignition switch is turned ON by the service engineer. At step 604, the master processor 104 of the BMS 103 detects the position of the ignition switch. The activation flag is generated by the master processor 104, on detecting the discharging of the battery pack 101 to the electrical loads 115 of the vehicle. On detecting the ignition switch is ON, at step 605, the remote monitoring device 104 enters advertising mode. After turning ON the ignition switch, the service engineer uses the diagnostics application 113 for scanning for the advertised battery information using the scan request at step 602. The master processor 104 arranges the battery information in a standard format (encrypted) at step 606 and transmits the formatted battery information as encrypted transmit data packets to the remote monitoring device 107 via the communication driver 106, at step 607. The wireless adapter 109 of the remote monitoring device 107 advertises the encrypted transmit data packets. The service engineer accesses the encrypted transmit data packets and the diagnostics application 113 decrypts the data packets to access the battery information. At step 603, the battery information is viewed in a prescribed format in the user interface 114 of the diagnostics application 113. [0043] Fig. 7 exemplarily illustrates a schematic diagram of exchange of battery information between the user device 112 and the BMS 103 for improving performance of the battery pack 101 at a service station. At the service station, the discharging condition of the battery pack 101 is established. That is, the battery pack 101 is connected to electrical loads 115 to discharge the battery pack 101 by supplying energy to the electrical loads 115. If incase, the battery pack 101 is used in a vehicle, on turning on the ignition switch of the vehicle, the battery pack 101 tends to discharge to supply the electrical loads 115, such as, lamps, hom, in the vehicle. At step 701, the ignition switch is turned ON by the service engineer. The service engineer connects with the BMS 103 using the connection request in the diagnostics application 113 at step 702. The master processor 104 detects the connection request from the diagnostics application 113 via the remote monitoring device 107. The master processor 104 enters into a peripheral mode for establishing the connection with the diagnostics application 113 at step 704. At step 705, the master processor 104 generates a passkey and transmits the passkey to the remote monitoring device 107 via the communication driver 106. The remote monitoring device 107 waits for a response from the diagnostics application 113 and transmits the key received from the diagnostics application 113 to the master processor 104. At step 706, the master processor 104 validates the passkey received from the diagnostics application 113 and if found appropriate, transmits an acknowledgement to the diagnostics application 113. Once the connection is established, the service engineer attempts to update the software of the BMS 103 in the diagnostics application 113, at step 707. The master processor 104 then detects the update request received from the diagnostics application 113 at step 708. The diagnostics application 113 also transmits the software patch to the master processor 104 via the wireless adapter 109. At step 709, the master processor 104 receives the software patch via the communication driver 106 from the remote monitoring device 107. At step 710, the master processor 104 performs the software update of the BMS 103. At step 711, the service engineer receives an acknowledgement of the BMS software updated in the diagnostics application 113 of the user device 112.

[0044] Fig. 8 exemplarily illustrates a schematic diagram of exchange of battery information between the user device 112 and the BMS 103 for performing diagnosis of the battery pack 101 at a service station. At the service station, the discharging condition of the battery pack 101 is established. That is, the battery pack 101 is connected to the electrical loads 115 to discharge the battery pack 101 by supplying energy to the electrical loads 115. If incase, the battery pack 101 is used in a vehicle, on turning on the ignition switch of the vehicle, the battery pack 101 tends to discharge to supply the electrical loads, such as, lamps, horn, in the vehicle. At step 801, the ignition switch is turned ON by the service engineer. The service engineer connects with the BMS 103 using the connection request in the diagnostics application 113 at step 802. Using the diagnostics application 113, the service engineer requests the history battery information using the history request in the user interface 114. At step 804, the master processor 104 detects the history request received from the wireless adapter 109 via the communication driver 106. At step 805, the master processor 104 gets the history battery information from the memory unit 105 of the BMS 103. In an embodiment, the master processor 104 fetches the history battery information from the remote server 111. At step 806, the master processor 104 performs encryption of the fetched history battery information to transmit as transmit data packets. At step 807, the master processor 104 transmits the encrypted transmit data packets to the diagnostics application 113 via the communication driver 106 and the wireless adapter 109. At step 808, the service engineer receives an acknowledgement of the history battery information, as a file from the flash memory 105 of the BMS 103 or the remote server 111, in the diagnostics application 113 of the user device 112.

[0045] Figs. 9A-9E exemplarily illustrate screenshots of the user interface 114 of the diagnostics application 113 in the user device 112. As exemplarily illustrated in Fig. 9A, the user interface 114 comprises four selection options 901, 902, 903, 904 for generating a scan request, a connection request, an update request, and a history request, respectively. On selecting the SCAN option 901 in the user interface 114, a scan request is transmitted to the wireless adapter 109 of the remote monitoring device 107. The advertised battery information is received and decrypted by the diagnostics application 113. The decrypted battery information displayed in the user interface 114 comprises unique identifier of the BMS 103, the cell parameters, the fault signal, etc. as exemplarily illustrated in Fig. 9B. On selecting the CONNECT option 902 in the user interface 114, a connection request is transmitted to the wireless adapter 109 of the remote monitoring device 107. The master processor 104 generates a passkey and transmits the passkey to the remote monitoring device 107 via the communication driver 106. The remote monitoring device 107 prompts the user to input a pass key in the user interface 114 to establish the connection with the BMS 103 as exemplarily illustrated in Fig. 9C. The master processor 104 validates the pass key received from the diagnostics application 113 and if found appropriate, transmits an acknowledgement to the diagnostics application 113.

[0046] On selecting the UPDATE option 903 in the user interface 114, an update request is transmitted to the wireless adapter 109 of the remote monitoring device 107. The master processor 104 prompts the user to select the new software patch to be transmitted to the master processor 104, apply it on the master processor 104, and subsequently receive an acknowledgement of the completion of the updation of the firmware of the BMS 103 as exemplarily illustrated in Fig. 9D. On selecting the REQUEST option 904 in the user interface 114, a history request is transmitted to the wireless adapter 109 of the remote monitoring device 107. The master processor 104 gets the history battery information from the memory unit 105 of the BMS 103 or from the remote server 111 and transmits encrypted transmit data packets to the diagnostics application 113 via the communication driver 106 and the wireless adapter 109. In the diagnostics application 113, an acknowledgement of the history battery information as a fde from the flash memory 105 of the BMS 103 or the remote server 111 is received as exemplarily illustrated in Fig. 9E. [0047] The battery pack and the method for wireless exchange of battery information between the BMS and the user device disclosed herein provides technical advancement in the field of battery technology as follows: The remote monitoring device is on-board the BMS of the battery pack. Thus, the remote monitoring device does not require any other external power source for its functioning. The wireless adapter employs Bluetooth Technology and the remote monitoring device is a Bluetooth Low Energy IC (BLE). Thus, the remote monitoring device is an energy efficient wireless communication device. In an embodiment, the auxiliary processor in the remote monitoring device functions as a secondary processing unit. The auxiliary processor can store important battery information and commands that are sent to the user device to perform required control action during the time of failure of the master processor. In an embodiment, the remote monitoring device is effectively useful in case of wiring harness failure, loss of communication between the battery packs, loss of communication between an external charger and the battery pack.

[0048] The wireless communication between the user device and the BMS is secure using encryption and decryption standards and prevents hacking of the battery information. The critical parameters and fault flags of the battery pack are stored in a remote server by the remote monitoring device. During the occurrence of failure in the pack, the large amounts of the stored battery information is retrieved and subjected to analysis for successful identification of causes of the failure of the battery pack. False interpretation of the failures is avoided, using the history battery information retrieved from the remote server. Also, prior to opening the battery pack to correct the issue, the wirelessly communicated battery status confirms safety in handling the battery pack, preventing catastrophes from occurring. Employing Bluetooth technology for wireless communication with the user device, allows the battery pack diagnostics to be done with any user device, not limited to specifically designed diagnostic couplers. Also, wirelessly transmitting the new software patch to update the firmware will allow the firmware of the BMS to be up- to-date with newly released software by the OEMs, without physical interference. This feature facilitates effortless, time saving, economical setup to update the software of the BMS, with improved accessibility to the battery pack. Additionally, the remote monitoring device is in a sleep mode and is configured to be periodically awake and advertise the battery information of the battery pack. The sleep mode ensures reduced power consumption of the battery pack and improves the life of the battery pack. If the battery pack is employed in a vehicle, the range of the vehicle improves with reduced power consumption due to the sleep mode. The history battery information allows the OEMs to analyze the on-road behavior of the vehicle.

[0049] Improvements and modifications may be incorporated herein without deviating from the scope of the invention.

Claims

We Claim:

1. A battery pack (101) comprising : a plurality of cells (102) defining total capacity of the battery pack (101); and a battery management system (BMS) (103) electrically coupled to the plurality of cells (102) for generating battery information, wherein the BMS (103) comprises a master processor (104) and a remote monitoring device (107) for wirelessly communicating the battery information with a user device (112).

2. The battery pack (101) of claim 1, wherein the user device (112) comprises a diagnostics application (113) for communicating with the remote monitoring device (107) of the BMS (103) of the battery pack (101).

3. The battery pack (101) of claim 2, wherein the remote monitoring device (107) comprises at least one auxiliary processor (108) and a wireless adapter (109) for exchanging the battery information with the user device (112).

4. The battery pack (101) of claim 3, wherein the master processor (104) comprises a communication driver (106) for communicating with the diagnostics application (113) through the wireless adapter ( 109) of the remote monitoring device (107).

5. The battery pack ( 101 ) of claim 3 , wherein the master processor (104) of the BMS (103) processes cell parameters and generates the battery information, and wherein the remote monitoring device (107) transmits the battery information to the diagnostics application (113) of the user device (112).

6. The battery pack ( 101 ) of claim 3 , wherein the remote monitoring device (107) receives a connection request from the diagnostics application (113), and wherein the master processor (104) establishes a connection between the remote monitoring device (107) and the diagnostics application (113) based on an authentication of the connection request.

7. The battery pack ( 101 ) of claim 3 , wherein the master processor ( 104) updates firmware of the BMS (103) using an update request remotely generated from the diagnostics application (113) of the user device (112).

8. The battery pack ( 101 ) of claim 3 , wherein the remote monitoring device (107) periodically advertises the battery information, and wherein the diagnostics application (113) transmits a scan request to the remote monitoring device (107) to receive the advertised battery information.

9. The battery pack ( 101 ) of claim 3 , wherein the diagnostics application (113) transmits a pack history request to the remote monitoring device (107), and wherein the diagnostics application ( 113) receives processed battery information from the remote monitoring device (107) corresponding to the transmitted pack history request.

10. The battery pack (101) of claim 3, wherein the diagnostics application (113) of the user device (112) provides one or more selection options on a user interface (114) for generating and transmitting a pack history request, a connection request, an update request, and a scan request.

11. The battery pack (101) of claim 3, wherein the wireless adapter (109) employs Bluetooth technology for exchanging the battery information with the user device (112). 12. The battery pack ( 101 ) of claim 1 , wherein the battery information comprises at least one of state of charge of the plurality of cells (102), voltages of the plurality of cells (102), charging current of each of the plurality of cells (102), discharging current of each of the plurality of cells ( 102), temperature of each of the plurality of cells (102), and an unique identifier of the battery pack (101).

13. The battery pack (101) of claim 1, wherein the master processor (104) stores the battery information chronologically in a remote server (111) periodically for analysing the performance of the battery pack (101) by the user.

14. The battery pack (101) of claim 1, wherein the master processor (104) of the BMS (103) activates the remote monitoring device (107), based on an activation flag. 15. The battery pack (101) of claim 14, wherein the master processor (104) generates the activation flag based on one of a discharging condition of the battery pack (101) and authentication of the diagnostics application (113) in the user device (112) by the master processor (104), based on a connection request received from the user device (112).

16. A method for wireless exchange of battery information between a battery pack (101) and a user device (112), the battery pack (101) comprising a plurality of cells (102) defining a total capacity of the battery pack (101), and a battery management system (BMS) (103) electrically coupled to the plurality of cells (102) for monitoring the performance of the battery pack (101), the BMS (103) comprising a master processor (104) and a remote monitoring device (107) for exchanging the battery information with the user device (112), and the user device (112) comprising a diagnostics application (113) for remotely monitoring health of the battery pack (101), the method comprising the steps of:

(at step 201) generating the battery information by processing cell parameters received from the plurality of cells (102) by the master processor (104) of the BMS (103),

(at step 202) activating the remote monitoring device (107) by the master processor (104) of the BMS (103) based on an activation flag,

(at step 203) advertising of the generated battery information by the activated remote monitoring device (107);

(at step 204) transmitting the advertised battery information by the activated remote monitoring device (107) to the user device (112) based on a scan request from the diagnostics application (113); and

(at step 205) storing the advertised battery information chronologically in a remote server periodically by the master processor (104) for analyzing the performance of the battery pack (101).

17. The method of claim 16, wherein the master processor (104) generates an activation flag based on one of a discharging condition of the battery pack (101) and authentication of the diagnostics application (113) in the user device (112) by the master processor (104) based on a connection request received from the user device (112).

18. The method of claim 16, further comprising performing a firmware update by the master processor (104) of the BMS (103), based on receiving an update request from the user device (112).

19. The method of claim 16, wherein the master processor (104) comprises a communication driver (106) for communicating with the diagnostics application (113) through a wireless adapter (109) of the remote monitoring device (107).

20. The method of claim 19, wherein the wireless adapter (109) employs Bluetooth technology for exchanging the battery information with the user device (112).

21. The method of claim 16, wherein the battery information comprises at least one of state of charge of the plurality of cells (102), voltages of the plurality of cells (102), charging current of each of the plurality of cells (102), discharging current of each of the plurality of cells (102), temperature of each of the plurality of cells (102), and an unique identifier of the battery pack (101).

22. The method of claim 16, wherein generating the battery information by the master processor (104) of the BMS (103) comprises fault detection of the plurality of cells (102), thermal management of the plurality of cells (102), determining total energy delivered by the battery pack (101), determining total number of charging and discharging cycles, and determining total operating time of the battery pack (101), based on the cell parameters.

23. The method of claim 16, further comprising transmitting a pack history request by the diagnostics application (113) to the remote monitoring device

(107) and receiving processed battery information from the remote monitoring device (107) corresponding to the transmitted pack history request, by the diagnostics application (113). 24. The method of claim 16, wherein the diagnostics application (113) of the user device (112) provides one or more selection options (901, 902, 903, 904) on a user interface (114) for generating and transmitting a pack history request, a connection request, an update request, and a scan request. 25. The method of claim 16, wherein the remote monitoring device (107) advertises the battery information periodically.