Battery cell anti-counterfeiting authentication method based on physical unclonable circuit

Abstract

The invention relates to the technical field of information security and communication, and discloses a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit, a battery management system comprises a module A, a module B and a module C. The module A comprises a Server unit, the module B comprises an MCU micro-control unit, and the module C comprises a battery cell management chip IC unit. A PUF soft model is embedded in the cell management chip IC unit. The method is divided into a registration stage S1, a bidirectional authentication stage S2 and a key updating stage S3. According to the method, a broadcast command and a return mechanism in daisy chain communication are fully utilized, bidirectional authentication of a battery cell management chip IC and an MCU micro-control unit is achieved in combination with a physical unclonable function, and only one physical unclonable function and a lightweight key hash algorithm need to be integrated in the battery cell management chip IC. And bidirectional authentication between the MCU micro-control unit and at most 256 battery cells can be realized by broadcasting a command for three times, and extremely high safety is ensured.

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 charging and discharging 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 safety risks in the battery system also include replacement and tampering attacks, which also bring huge safety hazards 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 technology 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 view of the above challenges, 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 it has gradually shown its limitations in the face of the challenges of cost and scalability of battery systems. In contrast, the daisy chain communication architecture has gradually become 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 safety 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 to ensure 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 view of the shortcomings of the prior art, 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 risks of identity forgery and tampering, and solving the problems mentioned in the above background technology.

[0005] To achieve the above-mentioned purpose, the present invention provides the following technical solutions: a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit; The battery management system includes an A module, a B module and a C module; 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; The method is divided into a registration phase S1, a two-way authentication phase S2 and a key update phase S3.

[0006] Preferably, the specific steps of the registration stage S1 are: S1.1: Each cell management chip IC generates stimulus response pairs (CRPs) during the test phase. The server unit uses the stimulus response pairs (CRPs) to build a PUF soft model in each cell management chip IC through machine learning. S1.2: The MCU microcontroller unit 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.

[0007] Preferably, the specific steps of the two-way authentication stage S2 are: S2.1: The MCU microcontroller 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 the C module generates a random sequence S and sends it back to the MCU microcontroller unit; S2.3: After receiving the random sequence S, the MCU microcontroller unit in module B generates a random sequence C as an incentive and sends the random sequence C to the server unit 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 hash operation to get the corresponding hash value ,Then the Server unit sends the generated hash value M´i to the MCU micro control 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: The battery management chip IC1 receives the 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: The cell management chip IC1 successfully completes the authentication of the MCU microcontroller unit, inputs the random sequence C as the stimulus into the PUF1 of the cell management chip IC1, generates the corresponding response R1, calculates the hash value M1 of the response R1, and sends the hash value M1 to the MCU microcontroller unit; 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´ vAre they equal? ​​If yes, proceed to step S2.9; otherwise, authentication fails and ends; S2.9: Input the random sequence C as 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: MCU microcontroller receives hash value M´ i With hash value M j and hash value M1, determine the hash value , and whether the hash value Mj, j∈[2,N] plus the hash value M1 is equal, if it is, the Server unit completes the authentication of the battery management chip IC, otherwise the authentication fails and ends.

[0008] Preferably, the specific steps of the key update stage 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´, each battery management chip IC performs XOR with its own key K to obtain a new key K new , used for the next authentication.

[0009] 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: 1. The battery cell anti-counterfeiting authentication method based on the physical unclonable circuit makes full use of the broadcast command and feedback mechanism in the daisy chain communication, and combines the physical unclonable function to realize the 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 physical unclonable function and a lightweight key hashing algorithm. Three broadcast commands can realize the two-way authentication between the MCU microcontroller unit and up to 256 battery cells, and ensure extremely high security.

[0010] 2. The battery cell anti-counterfeiting authentication method based on physical unclonable circuits maintains close communication between the Server unit and 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 safe 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 complexity of the authentication process while also improving the security of data transmission between batteries and the reliability of authentication. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] Figure 1 A schematic diagram of a battery management system for a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit proposed by the present invention; Figure 2 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; Figure 3 The present invention provides a two-way authentication flow chart of a battery cell anti-counterfeiting authentication method based on a physical unclonable circuit. DETAILED DESCRIPTION

[0012] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. 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 creative work are within the scope of protection of the present invention.

[0013] See also Figure 1-3 , a battery cell anti-counterfeiting authentication method based on physically unclonable circuits: The battery management system includes an A module, a B module and a C module; 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; The method is divided into a registration phase S1, a two-way authentication phase S2 and a key update phase S3.

[0014] 3. The specific steps of the registration stage S1 are: S1.1: Each cell management chip IC generates stimulus response pairs (CRPs) during the test phase. The server unit uses the stimulus response pairs (CRPs) to build a PUF soft model in each cell management chip IC through machine learning. S1.2: The MCU microcontroller unit 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] The specific steps of the two-way authentication phase S2 are: S2.1: The MCU microcontroller generates an authentication request Rq and sends it to each cell management chip IC in the C module via a daisy chain broadcast command; S2.2: The cell management chip IC1 in the C module generates a random sequence S and transmits it back to the MCU microcontroller unit through a daisy chain confirmation signal; S2.3: After receiving the random sequence S, the MCU microcontroller unit in module B generates a random sequence C as an incentive and sends the random sequence C to the server unit of module A through a secure channel; 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 hash operation to get the corresponding hash value ,Then the Server unit sends the generated hash value M´i to the MCU micro control unit through a secure channel; 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; S2.6: The battery management chip IC1 receives the 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: The cell management chip IC1 successfully completes the authentication of the MCU microcontroller unit, inputs the random sequence C as the stimulus into the PUF1 of the cell management chip IC1, generates the corresponding response R1, calculates the hash value M1 of the response R1, and sends the hash value M1 to the MCU microcontroller unit; 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 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: The MCU microcontroller receives the hash value M´ sent by the Server i and the hash value M1 and M sent from each battery management chip j , judge the hash value M'1 and the hash value M1 to the hash value M' i With hash value M j Are they equal? ​​If yes, the Server unit completes the authentication of the battery management chip IC. Otherwise, the authentication fails and ends.

[0016] 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.

[0017] System initialization: When the system starts, the server will generate the initial key and random number, and transmit this information securely 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 unique key and identity.

[0018] Bidirectional authentication process: During the authentication process, the MCU will send an authentication request to the cell management chip, including a random number and a key hash value. After receiving the request, the cell management chip will use its internal PUF to generate a response and perform a hash operation to ensure that the generated hash value matches the value sent by the MCU. If the match is successful, the cell management chip will confirm its identity and feedback the authentication result to the MCU.

[0019] Key update mechanism: In order to enhance the security of the system, it is necessary to perform key updates 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.

[0020] Fault handling and recovery mechanism: During the authentication process, if authentication fails, the system should have an automatic fault handling mechanism. The MCU will record the failed authentication attempt and decide whether to retry or enter safe mode based on the preset strategy. In safe mode, the system will limit the function of the battery cell to ensure that no service is provided to the outside world before the fault is resolved.

[0021] System monitoring and logging: To ensure the security and traceability of the system, all authentication processes and key update operations should be recorded in the system log. The server will regularly analyze these logs to identify abnormal activities and potential security risks. This measure not only helps to detect problems in a timely manner, but also provides a basis for subsequent security audits.

[0022] The cell management chip can manage the battery cells and realize two-way authentication with the MCU. Each cell management chip has a PUF embedded inside it, which is a special integrated circuit module inside the chip. It can use the inevitable process deviations of the chip, PCB and the cell itself during the manufacturing process to generate a non-clonable and non-removable "fingerprint" tag for the cell. Generally speaking, the "fingerprint" tag contains a set of chip-specific challenge response pairs (CRP). When a set of binary sequences is input as a challenge, a set of binary sequences can be output as a response, forming a unique mapping relationship.

[0023] 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.

[0024] The main control MCU implements communication and authentication with the server and the cell management chip. The MCU first needs to complete a two-way authentication process with the server to ensure that the transmission channel between the two is secure. Only after the authentication is passed can the MCU interact with other components in a trusted state. In the communication with the server, the MCU receives various instructions and information from the server, such as random sequences sent by the server and parameters related to the authentication of the cell management chip. It is also the key hub connecting the server and the cell management chip. It sends an incentive letter to the cell management chip according to the working status and requirements of the cell management chip to start the subsequent authentication process. The MCU also contains a key hash function HashK().

[0025] The server is mainly used to store the soft model information of each IC in the cell 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 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 cell management chip, such as historical authentication records, so as to comprehensively manage and trace the status and authentication history of the cell. This server can be a cloud server, a local server, or a centralized control system.

[0026] 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 command is sent and broadcasted to the battery management chip ICs at all levels through the daisy chain. After receiving the key K´, each battery management chip IC performs XOR with its own key K to obtain a new key K new , used for the next authentication.

[0027] In summary, the battery cell anti-counterfeiting authentication method based on the physical unclonable circuit makes full use of the broadcast command and feedback mechanism in the daisy chain communication, and combines the physical unclonable function to realize the 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 physical unclonable function and a lightweight key hashing algorithm. Three broadcast commands can realize the two-way authentication between the MCU microcontroller unit and up to 256 battery cells, and ensure extremely high security.

[0028] 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. It should be noted that the terms "include", "comprises" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, an element defined by the sentence "comprises a ..." does not exclude the existence of other identical elements in the process, method, article or device including the element.

[0029] Although 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 the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present 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 in that: The battery management system includes an A module, a B module and a C module; 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; The method is divided into a registration phase S1, a two-way authentication phase S2 and a key update phase S3.

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 stage S1 are: S1.1: Each cell management chip IC generates stimulus response pairs (CRPs) during the test phase. The server unit uses the stimulus response pairs (CRPs) to build a PUF soft model in each cell management chip IC through machine learning. S1.2: The MCU microcontroller unit 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.

3. The method for anti-counterfeiting authentication of a battery cell based on a physical unclonable circuit according to claim 1, characterized in that: The specific steps of the two-way authentication stage S2 are: S2.1: The MCU microcontroller 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 the C module generates a random sequence S and sends it back to the MCU microcontroller unit; S2.3: After receiving the random sequence S, the MCU microcontroller unit in module B generates a random sequence C as an incentive and sends the random sequence C to the server unit 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 hash operation to get the corresponding hash value , then the server unit will generate the hash value M´ i Send to MCU micro control 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: The battery management chip IC1 receives the 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: The cell management chip IC1 successfully completes the authentication of the MCU microcontroller unit, inputs the random sequence C as the stimulus into the PUF1 of the cell management chip IC1, generates the corresponding response R1, calculates the hash value M1 of the response R1, and sends the hash value M1 to the MCU microcontroller unit; 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 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: MCU microcontroller receives hash value M´ i With hash value M j and hash value M1, determine the hash value , and the hash value M j , j∈[2,N] plus the hash value M1 are equal, if yes, the Server unit completes the authentication of the battery management chip IC, otherwise the authentication fails and ends.

4. The method for anti-counterfeiting authentication of a battery cell based on a physical unclonable circuit according to claim 1, characterized in that: The specific steps of the key update stage 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´, each battery management chip IC performs XOR with its own key K to obtain a new key K new , used for the next authentication.

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