A battery cell anti-counterfeiting authentication method based on physically unclonable circuits

Abstract

The present invention relates to the field of information security and communication technology, and discloses a battery cell anti-counterfeiting authentication method based on a physically unclonable circuit. The battery management system includes a module A, a module B, and a module C. Module A includes a Server unit, module B includes an MCU microcontroller unit, and module C includes a battery cell management chip IC unit. The battery cell management chip IC unit is embedded with a PUF soft model. The method is divided into a registration phase S1, a two-way authentication phase S2, and a key update phase S3. The method makes full use of the broadcast command and return mechanism in daisy chain communication, and combines a physically unclonable function to realize two-way authentication of the battery cell management chip IC and the MCU microcontroller unit. Only one physically unclonable function and a lightweight key hashing algorithm need to be integrated inside the battery cell management chip IC. Three broadcast commands can realize two-way authentication between the MCU microcontroller unit and up to 256 battery cells, and ensure extremely high security.

Description

Technical Field

[0001] The present invention relates to the field of information security and communication technology, and in particular to a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit. Background Art

[0002] With the widespread popularity of electronic devices, batteries, as their key components, play an indispensable role in providing power support for devices. From mobile devices to power tools, from electric vehicles to energy storage systems, the performance and safety of batteries directly affect the user experience of electronic devices and the safety of users' lives and property. Therefore, battery-powered applications need to be equipped with a battery management system (BMS). BMS is a comprehensive hardware and software system that protects and manages batteries. It is not only responsible for monitoring the health of the battery, such as the state of charge (SOC) and the state of health (SOH), but also controls the battery's charge and discharge process through circuits, and exchanges information with external systems through communication interfaces to ensure the safe operation of the battery and extend its life and performance. However, from a security perspective, the current BMS faces many challenges, including resource limitations, security vulnerabilities, firmware and software vulnerabilities, and communication security issues. In addition, the security risks in the battery system also include replacement and tampering attacks, which also bring huge security risks to consumers and manufacturers and disrupt the market order. Some attackers may be driven by economic interests to produce and sell low-quality batteries. Although these batteries are low-cost, they cannot guarantee safety performance and durability. By replacing them in the supply chain, exchanging them during service and maintenance, or directly tampering with the battery's circuits and software, attackers can obtain improper economic benefits at the expense of product quality and user safety. Although traditional anti-counterfeiting methods such as barcodes, QR codes, RFID and encryption technologies are widely used, they all have limitations. For example, barcodes and QR codes are easy to copy, RFID tags can be cloned and their security depends on encryption algorithms and communication protocols. Encryption technology is difficult to implement in a resource-constrained environment and key leakage will cause the anti-counterfeiting system to collapse.

[0003] In response to the above challenges, and considering the current development trend of BMS communication architecture—the evolution from traditional CAN communication architecture to daisy-chain communication architecture—CAN communication, as a traditional BMS communication architecture, has been widely used, but has gradually revealed its limitations when faced with the cost and scalability challenges of battery systems. In contrast, the daisy-chain communication architecture has become increasingly popular in recent years. It connects battery cells in a serialized manner to form a closed-loop network, significantly reducing the number of communication interfaces and cables, simplifying the overall system structure and reducing system costs. It aims to combine the daisy-chain communication architecture and improve the security of the battery system to prevent the risk of identity forgery and tampering. This technical solution fully considers the resource and cost limitations of the battery system, ensuring that it can still provide efficient security without significantly increasing computing and energy consumption. The key security authentication process is completed independently between the main control unit and each battery cell to ensure the confidentiality and reliability of core data verification. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the present invention provides a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit, which has the advantages of simplifying the overall system structure and reducing system costs, preventing the risk of identity forgery and tampering, and solving the problems mentioned in the above background technology.

[0005] To achieve the above-mentioned object, the present invention provides the following technical solutions: a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit;

[0006] The authentication method is applied to a battery management system;

[0007] The battery management system includes module A, module B and module C;

[0008] The A module includes a Server unit;

[0009] The B module includes an MCU micro control unit;

[0010] The C module includes a battery management chip IC unit, and the battery management chip IC unit has a PUF soft model embedded therein;

[0011] This method is divided into a registration phase S1, a two-way authentication phase S2 and a key update phase S3.

[0012] Preferably, the specific steps of the registration stage S1 are:

[0013] S1.1: Each cell management IC generates stimulus-response pairs (CRPs) during the testing phase. The server unit uses these CRPs through machine learning to build a PUF soft model within each cell management IC.

[0014] S1.2: The MCU microcontroller randomly generates a key K and sends it to each cell management chip IC. After receiving the key K, each cell management chip IC calculates the hash function Hash k () and save to complete the registration.

[0015] Preferably, the specific steps of the two-way authentication stage S2 are:

[0016] S2.1: The MCU generates an authentication request Rq and sends it to each cell management chip IC in the C module;

[0017] S2.2: The cell management chip IC1 in module C generates a random sequence S and sends it back to the MCU microcontroller unit;

[0018] S2.3: After receiving the random sequence S, the MCU in module B generates a random sequence C as an incentive and sends it to the server in module A.

[0019] S2.4: After receiving the random sequence C, the server unit in module A uses the random sequence C as a stimulus to deploy the soft model PUF of each PUF in the server unit. i , made of soft model PUF´ i Output the corresponding response R´ i , and finally the response R´ i Perform keyless hashing to obtain the corresponding hash value , then the server unit will generate the hash value M´ i Send to MCU micro control unit;

[0020] S2.5: Each cell management chip IC in module C uses the key K to perform a hash operation on the random sequence S to obtain a hash value M´ v , the hash value M´ v , random sequence C and random sequence S are sent to the cell management chip IC1;

[0021] S2.6: Cell management chip IC1 receives hash value M´ v , random sequence C and random sequence S, and then send the hash value M' to the battery management chip IC2 v , random sequence C and random sequence S, and read the random sequence S and key K to calculate the hash value Hash K (S), compare the hash value Hash K (S) and hash value M´ v Are they equal? ​​If yes, proceed to step S2.7; otherwise, authentication fails and ends.

[0022] S2.7: Cell management chip IC1 successfully authenticates the MCU, inputs random sequence C as a stimulus into PUF1 of cell management chip IC1, generates a corresponding response R1, calculates a hash value M1 of response R1, and sends the hash value M1 to the MCU.

[0023] S2.8: Each subsequent cell management chip IC receives the hash value M´ v , random sequence C and random sequence S, read the key K, and calculate the hash value Hash after receiving the random sequence S K (S), compare the hash value Hash K (S) and hash value M´ v Are they equal? ​​If yes, proceed to step S2.9; otherwise, authentication fails and ends.

[0024] S2.9: Input the random sequence C as the stimulus to PUF2 to PUF n , and generate the response R of each battery management chip IC j , then the response R j Perform hash operation to obtain the corresponding hash value M j ,j∈[2,N], and finally the hash values ​​M generated by each j , and send it back to the MCU micro control unit;

[0025] S2.10: The MCU receives the hash value M´ i With hash value M j and hash value M1, judge the hash value , and the hash value M j , j∈[2,N] plus the hash value M1 are equal. If so, the Server unit completes the authentication of the battery management chip IC, otherwise the authentication fails and ends.

[0026] Preferably, the specific steps of the key update stage S3 are:

[0027] After the MCU microcontroller unit of module B and the battery management chip IC of each level in module C complete mutual authentication, a new key K' is generated using a random number generator, and then the key K is calculated. new , K new = K´⊕K. After the calculation is completed, the key K update instruction is sent and sent to the battery management chip ICs at all levels through the daisy chain. After receiving the key K´, the battery management chip ICs at all levels perform XOR with their own key K to obtain the new key K new , used for the next authentication.

[0028] Compared with the prior art, the present invention provides a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit, which has the following beneficial effects:

[0029] 1. This battery cell anti-counterfeiting authentication method based on a physically unclonable circuit fully utilizes the broadcast command and feedback mechanism in daisy-chain communication, and combines it with a physically unclonable function to achieve two-way authentication of the battery cell management chip IC and the MCU microcontroller unit. The battery cell management chip IC only needs to integrate a physically unclonable function and a lightweight key hashing algorithm. Three broadcast commands can achieve two-way authentication between the MCU microcontroller unit and up to 256 battery cells, ensuring extremely high security.

[0030] 2. This battery cell anti-counterfeiting authentication method based on a physical unclonable circuit maintains close communication between the server unit, the MCU microcontroller unit, and the battery cell management chip IC. It communicates with the MCU microcontroller unit through a secure channel to ensure the secure transmission of information. At the same time, the server unit also communicates with the battery cell management chip IC through a daisy chain to receive and send various authentication-related information to achieve efficient operation of the entire authentication system. Combined with daisy chain point-to-point communication, it reduces overhead and the complexity of the authentication process while also improving the security of data transmission between battery cells and the reliability of authentication. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 Schematic diagram of a battery management system for a cell anti-counterfeiting authentication method based on a physical unclonable circuit proposed in the present invention;

[0032] Figure 2 This is a two-way authentication flow chart of a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit proposed by the present invention;

[0033] Figure 3 This is a two-way authentication flow chart of a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit proposed by the present invention. DETAILED DESCRIPTION

[0034] The following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0035] See also Figure 1-3 , a battery cell anti-counterfeiting authentication method based on physical unclonable circuits:

[0036] The authentication method is applied to a battery management system;

[0037] The battery management system includes module A, module B and module C;

[0038] The A module includes a Server unit;

[0039] The B module includes an MCU micro control unit;

[0040] The C module includes a battery management chip IC unit, and the battery management chip IC unit has a PUF soft model embedded therein;

[0041] This method is divided into a registration phase S1, a two-way authentication phase S2 and a key update phase S3.

[0042] The specific steps of the registration phase S1 are:

[0043] S1.1: Each cell management IC generates stimulus-response pairs (CRPs) during the testing phase. The server unit uses these CRPs through machine learning to build a PUF soft model within each cell management IC.

[0044] S1.2: The MCU microcontroller randomly generates a key K and sends it to each cell management chip IC. After receiving the key K, each cell management chip IC calculates the hash function Hash k () and save to complete the registration.

[0045] The specific steps of the two-way authentication phase S2 are:

[0046] S2.1: The MCU generates an authentication request Rq and sends it to each cell management chip IC in the C module via a daisy chain broadcast command;

[0047] S2.2: The cell management chip IC1 in module C generates a random sequence S and transmits it back to the MCU via a daisy chain confirmation signal;

[0048] S2.3: After receiving the random sequence S, the MCU in module B generates a random sequence C as an incentive and sends it to the server in module A through a secure channel.

[0049] S2.4: After receiving the random sequence C, the server unit in module A uses the random sequence C as a stimulus to deploy the soft model PUF of each PUF in the server unit. i , made of soft model PUF´ i Output the corresponding response R´ i , and finally the response R´ i Perform keyless hashing to obtain the corresponding hash value , then the server unit will generate the hash value M´i Send to MCU microcontroller unit through secure channel;

[0050] S2.5: Each cell management chip IC in module C uses the key K to perform a hash operation on the random sequence S to obtain a hash value M´ v , the hash value M´ v , random sequence C and random sequence S are sent to the cell management chip IC1 through a broadcast command;

[0051] S2.6: Cell management chip IC1 receives hash value M´ v , random sequence C and random sequence S, and then send the hash value M' to the battery management chip IC2 v , random sequence C and random sequence S, and read the random sequence S and key K to calculate the hash value Hash K (S), compare the hash value Hash K (S) and hash value M´ v Are they equal? ​​If yes, proceed to step S2.7; otherwise, authentication fails and ends.

[0052] S2.7: Cell management chip IC1 successfully authenticates the MCU, inputs random sequence C as a stimulus into PUF1 of cell management chip IC1, generates a corresponding response R1, calculates a hash value M1 of response R1, and sends the hash value M1 to the MCU.

[0053] S2.8: Each subsequent cell management chip IC receives the hash value M´ v , random sequence C and random sequence S, read the key K, and calculate the hash value Hash after receiving the random sequence S K (S), compare the hash value Hash K (S) and hash value M´ v Are they equal? ​​If yes, proceed to step S2.9; otherwise, authentication fails and ends.

[0054] S2.9: Input the random sequence C as the stimulus to PUF2 to PUF n , and generate the response R of each battery management chip IC j , then the response R j Perform hash operation to obtain the corresponding hash value M j ,j∈[2,N], and finally the hash values ​​M generated by each j , and send it back to the MCU micro control unit;

[0055] S2.10: The MCU receives the hash value M' sent by the Server. i With the hash value M1 and M sent from each battery management chipj , judge the hash value M'1 and the hash value M1 to hash value M' i With hash value M j Are the corresponding equal? ​​If yes, the server unit completes the authentication of the battery management chip IC. Otherwise, the authentication fails and ends.

[0056] S2.10 specifically determines whether the hash value M'1 is equal to the hash value M1, and whether the hash value M'2 is equal to the hash value M2, until the hash value M' n Is it consistent with the hash value M n Equal, judge step by step.

[0057] System initialization: When the system starts, the server generates an initial key and random number and securely transmits this information to the MCU and the cell management chip. The MCU is responsible for distributing this information to the connected cell management chips and ensuring that each cell management chip can independently generate its own unique key and identity.

[0058] Bidirectional authentication process: During authentication, the MCU sends an authentication request to the cell management chip, including a random number and a key hash value. Upon receiving the request, the cell management chip generates a response using its internal PUF and performs a hash operation to ensure that the generated hash value matches the value sent by the MCU. If a match is found, the cell management chip confirms its identity and returns the authentication result to the MCU.

[0059] Key update mechanism: In order to enhance the security of the system, it is necessary to update the key regularly. During the key update phase, the MCU will generate a new key K new After receiving the new key, each cell management chip will perform an XOR operation with its own old key to generate a new key K. new This mechanism ensures the dynamic nature of the key and effectively prevents potential security threats.

[0060] Fault handling and recovery mechanisms: If authentication fails during the authentication process, the system should have an automatic fault handling mechanism. The MCU will record the failed authentication attempt and, based on pre-set policies, decide whether to retry or enter safe mode. In safe mode, the system will restrict the cell's functionality, ensuring that no service is provided until the fault is resolved.

[0061] System Monitoring and Logging: To ensure system security and traceability, all authentication processes and key updates are recorded in system logs. The server will regularly analyze these logs to identify unusual activity and potential security risks. This measure not only helps identify issues promptly but also provides a basis for subsequent security audits.

[0062] The cell management chip manages individual battery cells and enables bidirectional authentication with the MCU. Each cell management chip is embedded with a PUF, a specialized integrated circuit module within the chip. This module leverages the inevitable manufacturing variations of the chip, PCB, and cell itself to generate an unclonable and non-removable "fingerprint" tag for the cell. Generally, this "fingerprint" tag consists of a unique set of chip-specific challenge-response pairs (CRPs). When a binary sequence is input as a challenge, a binary sequence is output as a response, forming a unique mapping relationship.

[0063] Each cell management chip also contains a key hash function HashK(), which uses a key to generate a hash value to ensure the integrity and authenticity of the data. This can be achieved by using, but is not limited to, lightweight hash algorithms such as SPONGENT.

[0064] The main control MCU implements communication and authentication with the server and cell management chip. The MCU first needs to complete a two-way authentication process with the server to ensure the security of the transmission channel between the two. Only after authentication is successful can the MCU interact with other components in a trusted state. During communication with the server, the MCU receives various instructions and information from the server, such as the random sequence sent by the server and parameters related to cell management chip authentication. It is also the key hub connecting the server and the cell management chip. Based on the operating status and requirements of the cell management chip, it sends an activation letter to the cell management chip to initiate the subsequent authentication process. The MCU also contains a key hash function HashK().

[0065] The server is mainly used to store the soft model information of each IC in the battery management chip (including the stimulus response pairs of each PUF), send random sequences, and provide data support for MCU authentication. In a secure environment, a large amount of CRP data of the PUF unit inside the battery cell is collected, and a soft model of the PUF is established using a machine learning algorithm. The model parameters are stored on the server side, so that the CRPs of the physical unclonable function can be predicted without using physical hardware, thereby avoiding the storage of a large number of CRPs. In addition to the soft model information, the server also needs to store other important data related to the battery management chip, such as historical authentication records, so as to comprehensively manage and trace the status and authentication history of the battery cell. This server can be a cloud server, a local server, or a centralized control system.

[0066] The specific steps of the key update phase S3 are:

[0067] After the MCU microcontroller unit of module B and the battery management chip IC of each level in module C complete mutual authentication, a new key K' is generated using a random number generator, and then the key K is calculated. new , K new = K´⊕K. After the calculation is completed, the key K update instruction is sent and sent to the battery management chip ICs at all levels through the daisy chain in the form of broadcast. After receiving the key K´, the battery management chip ICs at all levels perform XOR with their own key K to obtain the new key K new , used for the next authentication.

[0068] In summary, this battery cell anti-counterfeiting authentication method based on a physically unclonable circuit makes full use of the broadcast command and feedback mechanism in daisy-chain communication, and combines the physically unclonable function to realize two-way authentication of the battery cell management chip IC and the MCU microcontroller unit. The battery cell management chip IC only needs to integrate a physically unclonable function and a lightweight key hashing algorithm. Three broadcast commands can realize two-way authentication between the MCU microcontroller unit and up to 256 battery cells, and ensure extremely high security.

[0069] In addition, the server unit maintains close communication with the MCU microcontroller unit and the battery management chip IC. It communicates with the MCU microcontroller unit through a secure channel to ensure the safe transmission of information. At the same time, the server unit also communicates with the battery management chip IC through a daisy chain to receive and send various authentication-related information to achieve efficient operation of the entire authentication system. Combined with daisy chain point-to-point communication, it reduces overhead and complexity of the authentication process while also improving the security of data transmission between batteries and the reliability of authentication.

[0070] It should be noted that the terms "comprises," "includes," or any other variations thereof are intended to encompass non-exclusive inclusion, such that a process, method, article, or apparatus that includes a series of elements includes not only those elements but also other elements not explicitly listed, or elements inherent to such process, method, article, or apparatus. In the absence of further limitations, an element defined by the phrase "comprises a ..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0071] While embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions, and variations may be made to these embodiments without departing from the principles and spirit of the invention, and that the scope of the invention is defined by the appended claims and their equivalents.

Claims

1. A battery cell anti-counterfeiting authentication method based on a physically unclonable circuit, characterized by: The authentication method is applied to a battery management system; The battery management system includes module A, module B and module C; The A module includes a Server unit; The B module includes an MCU micro control unit; The C module includes a battery management chip IC unit, and the battery management chip IC unit has a PUF soft model embedded therein; This method is divided into a registration phase S1, a two-way authentication phase S2 and a key update phase S3; The specific steps of the two-way authentication stage S2 are: S2.1: The MCU generates an authentication request Rq and sends it to each cell management chip IC in the C module; S2.2: The cell management chip IC1 in module C generates a random sequence S and sends it back to the MCU microcontroller unit; S2.3: After receiving the random sequence S, the MCU in module B generates a random sequence C as an incentive and sends it to the server in module A. S2.4: After receiving the random sequence C, the server unit in module A uses the random sequence C as a stimulus to deploy the soft model PUF of each PUF in the server unit. i ， Made of soft model PUF´ i Output the corresponding response R´ i , and finally the response R´ i Perform keyless hashing to obtain the corresponding hash value ,Then the Server unit sends the generated hash value M´i to the MCU microcontroller unit; S2.5: Each cell management chip IC in module C uses the key K to perform a hash operation on the random sequence S to obtain a hash value M´ v , the hash value M´ v , random sequence C and random sequence S are sent to the cell management chip IC1; S2.6: Cell management chip IC1 receives hash value M´ v , random sequence C and random sequence S, and then send the hash value M' to the battery management chip IC2 v , random sequence C and random sequence S, and read the random sequence S and key K to calculate the hash value Hash K (S), compare the hash value Hash K (S) and hash value M´ v Are they equal? ​​If yes, proceed to step S2.7; otherwise, authentication fails and ends. S2.7: Cell management chip IC1 successfully authenticates the MCU, inputs random sequence C as a stimulus into PUF1 of cell management chip IC1, generates a corresponding response R1, calculates a hash value M1 of response R1, and sends the hash value M1 to the MCU. S2.8: Each subsequent cell management chip IC receives the hash value M´ v , random sequence C and random sequence S, read the key K, and calculate the hash value Hash after receiving the random sequence S K (S), compare the hash value Hash K (S) and hash value M´ v Are they equal? ​​If yes, proceed to step S2.9; otherwise, authentication fails and ends. S2.9: Input the random sequence C as the stimulus to PUF2 to PUF n , and generate the response R of each battery management chip IC j , then the response R j Perform hash operation to obtain the corresponding hash value M j ,j∈[2,N], and finally the hash values ​​M generated by each j , and send it back to the MCU micro control unit; S2.10: Determine whether the hash value M'1 is equal to the hash value M1, and whether the hash value M'2 is equal to the hash value M2, until the hash value M' is determined. n Is it consistent with the hash value M n If they are equal, the server unit completes the authentication of the battery management chip IC. Otherwise, the authentication fails and ends.

2. A battery cell anti-counterfeiting authentication method based on a physical unclonable circuit according to claim 1, characterized in that The specific steps of the registration phase S1 are: S1.1: Each cell management IC generates stimulus-response pairs (CRPs) during the testing phase. The server unit uses these CRPs through machine learning to build a PUF soft model within each cell management IC. S1.2: The MCU microcontroller unit randomly generates a key K and sends it to each cell management chip IC. Each cell management chip IC also contains a key hash function HashK() and stores it. By using a key to generate a hash value, registration is completed.

3. The battery cell anti-counterfeiting authentication method based on a physical unclonable circuit according to claim 1, characterized in that: The specific steps of the key update phase S3 are: After the MCU microcontroller unit of module B and the battery management chip IC of each level in module C complete mutual authentication, a new key K' is generated using a random number generator, and then the key K is calculated. new , K new = K´⊕K. After the calculation is completed, the key K update instruction is sent and sent to the battery management chip ICs at all levels through the daisy chain. After receiving the key K´, the battery management chip ICs at all levels perform XOR with their own key K to obtain the new key K new , used for the next authentication.

Images