Description:TECHNICAL FIELD
[0001] The present disclosure generally relates to the operation of batteries. More particularly, the disclosure relates to a method, device, and system for cell equalization during charging of a battery.
BACKGROUND
[0002] This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present disclosure, which are described below. This disclosure is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not just as admissions of prior art.
[0003] In today’s world, batteries play a pivotal role in powering various devices and systems, from portable electronics to electric vehicles and renewable energy storage. Batteries are electrochemical devices that store energy in chemical form and convert it into electrical energy when needed. They consist of one or more electrochemical cells, each containing a positive electrode (cathode), a negative electrode (anode), and an electrolyte. When a load is connected to the battery, a chemical reaction occurs, resulting in the flow of electrons through an external circuit, thereby generating electrical current.
[0004] As the demand for energy storage solutions grows, so does the need for efficient management and monitoring of battery systems. This is where Battery Management Systems (BMS) come into play. BMS are crucial for ensuring the optimal performance, safety, and longevity of battery systems.
[0005] A BMS is essential for several reasons, including cell balancing, state-of-charge (SoC) monitoring, thermal management, and fault detection & safety. In multi-cell batteries, individual cells may have variations in their characteristics, such as capacity and internal resistance. A BMS monitors and balances the charge/discharge of each cell, preventing imbalances that can lead to reduced performance or even failure. In SoC monitoring, a BMS accurately measures the SoC of the battery, providing crucial information for estimating available energy and preventing overcharging or deep discharging, which can damage the battery. In thermal management, batteries can generate heat during operation, which can degrade performance and compromise safety. A BMS monitors and controls the temperature of the battery, preventing overheating and optimizing its operation. In fault detection and safety, BMS systems incorporate various protective measures, such as overvoltage protection, undervoltage protection, and short circuit detection. These features enhance safety by preventing dangerous situations and reducing the risk of fire or explosion.
[0006] One major issue with BMS is the unreliability of state estimation algorithms. Various model-based condition monitoring algorithms have been proposed to estimate battery states, including the Kalman filter and the dual sliding mode observer. Some commonly used battery models in the BMS are electrical models, electrochemical models, thermal models, and coupled models. However, due to the complex internal principles and uncertain working conditions, it is difficult to establish a battery model that can accurately represent the battery’s dynamic characteristics. Therefore, more complex data-driven algorithms are required to accurately estimate SoC, SoH, and Remaining Useful Life (RUL) throughout the entire lifespan of the battery. However, despite the development of these algorithms, they cannot be integrated into the BMS due to its limited computing capability and data storage.
[0007] Efficient estimation of battery state-of-charge (SoC), state-of-health (SoH), and remaining useful life (RUL) is crucial for optimal battery management throughout its lifespan. However, current BMS face limitations in integrating complex data-driven algorithms due to limited computing capability and data storage capacity.
[0008] Another aspect of the optimal battery management is to employ effective cell-balancing methodologies. Active cell balancing methods remove charge from one or more high cells and deliver the charge to one or more low cells. Dissipative techniques find the high cells in the pack, and remove excess energy through a resistive element until their charges match the low cells.
[0009] Existing methods for cell balancing or equalization often rely on active balancing during discharge or external circuitry for equalization during charging. However, these methods can be complex, expensive, and may not effectively address voltage imbalances or provide sufficient protection against overcharging or deep discharging.
[0010] To overcome these challenges, a comprehensive solution is required. This solution should enable accurate estimation of battery characteristics while also performing vital functions such as cell balancing, state-of-charge (SoC) monitoring, thermal management, and fault detection & safety.
SUMMARY
[0011] This application introduces a comprehensive solution that encompasses a cell equalization method, a device, a chip, and a battery management system to enhance the performance, safety, and longevity of battery system(s). This solution not only accurately estimates battery characteristics but also incorporates essential functions such as cell balancing, state-of-charge (SoC) monitoring, thermal management, and fault detection & safety.
[0012] A method for cell equalization during charging of a battery is disclosed herein. The method comprising the steps of monitoring voltages of each cell within the battery and setting an adjustable boost voltage for the battery based on the monitored cell voltages. The method further comprising the steps of reducing the boost voltage by a predetermined value when the cell voltages are imbalanced, charging the battery up to the reduced boost voltage, and providing a relaxation period for the battery cells after the charging.

[0013] Optionally, the method further comprising the steps of checking equalization of cell voltages after the relaxation period and adjusting the boost voltage to a reduced level in the subsequent charging cycle based on the determined imbalance in the cell voltages during the cell equalization.

[0014] Optionally, the relaxation period for the battery cells is between 30-60 minutes.

[0015] Optionally, the method further comprising the steps of sensing temperature of each cell of the battery and adjusting the boost voltage based on the sensed temperature.

[0016] Optionally, adjusting the boost voltage based on the sensed temperature comprises decreasing the boost voltage when the temperature of the cells increases.

[0017] Optionally, the method further comprising the step of performing inbuilt warranty calculation based on operation of the battery.

[0018] A device for cell equalization using relaxation-based charging technique is disclosed herein. The device comprising a control circuit configured to monitor the voltages of each cell within a battery and set an adjustable boost voltage for the battery based on the monitored cell voltages. The control circuit further configured to reduce the boost voltage by a predetermined value when the cell voltages are imbalanced and charge the battery up to the reduced boost voltage. The device further comprising a relaxation period control mechanism configured to provide a relaxation period for the battery cells after the charging.

[0019] Optionally, the device further comprising a comparison mechanism configured to check the equalization of the cell voltages after the relaxation period and the control circuit further configured to adjust the boost voltage to a reduced level in the subsequent charging cycle based on the determined imbalance in the cell voltages during the cell equalization.

[0020] Optionally, the device further comprising a charging control mechanism configured to reduce the boost voltage in the subsequent charging cycle based on the determined imbalance in the cell voltages for cell equalization.

[0021] Optionally, the device further comprising a control module configured to control the boost voltage setting, relaxation period, and subsequent boost voltage reduction based on the individual cell voltages.

[0022] Optionally, the device further comprising temperature sensors installed around the battery cells and a temperature sensing mechanism to adjust the boost voltage based on the sensed cell temperature.

[0023] Optionally, the boost voltage reduction and subsequent boost voltage reduction during charging cycles are controlled by communication between the control circuit (401) and a battery management system (BMS) using Universal Asynchronous Receiver-Transmitter (UART) or other suitable communication technologies.

[0024] A system comprising a battery management system in operative communication with a battery having a device for cell equalization as claimed above.
[0025] The cell equalization method and device ensures that individual cells within a battery maintain balanced charge and discharge levels. By preventing imbalances among cells, the method may promote consistent performance and extends the overall lifespan of the battery system.
[0026] Further, the method and device enable accurate estimation of battery characteristics such as SoC, state-of-health (SoH), remaining useful life (RUL) and provides valuable information for optimal battery management. In addition to cell equalization and accurate estimation of battery characteristics, the solution encompasses several essential functions. The state-of-charge (SoC) monitoring feature allows for precise measurement of the available energy within the battery, enabling efficient utilization, and preventing overcharging or deep discharging that can cause damage.
[0027] Thermal management is another key aspect of the solution, as it actively monitors and controls the temperature of the battery. By preventing overheating and optimizing operation, this feature improves both performance and safety of the battery.
[0028] The method, device, and system incorporates fault detection and safety measures to ensure the reliable and secure operation of the battery or a battery system. These protective measures include overvoltage protection, undervoltage protection, short circuit detection, reducing the risk of accidents, and enhancing user safety.
[0029] Further, the method, device, and system disclosed herein offer several advantages over existing cell equalization techniques. By utilizing a relaxation-based charging technique, the disclosure achieves effective cell equalization during battery charging without the need for complex active balancing or external circuitry. This simplifies the implementation and reduces costs.
[0030] The disclosure ensures balanced cell voltages, thereby enhancing overall battery performance and extending the battery’s lifespan. The relaxation period allows cells to stabilize, reducing the risk of overcharging or deep discharging.
[0031] Additionally, the device can integrate with a battery management system (BMS) using communication technologies such as Universal Asynchronous Receiver-Transmitter (UART), enabling control and monitoring of the boost voltage reduction and subsequent charging cycles.
[0032] In summary, the method, device, and system described herein provide an efficient and cost-effective solution for cell equalization during battery charging, offering improved performance, extended lifespan, and enhanced safety for battery systems.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] To further clarify advantages and features of the present disclosure, a more particular description of the disclosure will be rendered by reference to specific embodiments thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical embodiments of the disclosure and are therefore not to be considered limiting of its scope. The disclosure will be described and explained with additional specificity and detail with the accompanying drawings in which:
[0034] Figure 1 illustrates schematic diagram of a battery in accordance with an embodiment of the disclosure;
[0035] Figure 2 illustrates a schematic diagram of battery management system (BMS) in operative communication with a battery in accordance with an embodiment of the disclosure;
[0036] Figure 3 illustrates a flowchart outlining the cell equalization method in accordance with an embodiment of the disclosure;
[0037] Figure 4 illustrates a block diagram of a device for cell equalization in batteries in accordance with an embodiment of the disclosure;
[0038] Figure 5 illustrates a block diagram of a system in accordance with an embodiment of the disclosure;
[0039] Figure 6(a)-(b) illustrates a pictorial representation of the average imbalance in each cell’s voltages at a specific time during charging of the battery in accordance with an embodiment of the disclosure; and
[0040] Figure 7 illustrates a graph of voltage vs. time for each cell in the battery in accordance with an embodiment of the disclosure.
DETAILED DESCRIPTION
[0041] For the purpose of promoting an understanding of the principles of the disclosure, reference will now be made to the embodiment illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the disclosure is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the disclosure as illustrated therein being contemplated as would normally occur to one skilled in the art to which the disclosure relates.
[0042] It will be understood by those skilled in the art that the foregoing general description and the following detailed description are exemplary and explanatory of the disclosure and are not intended to be restrictive thereof. Throughout the patent specification, a convention employed is that in the appended drawings, like numerals denote like components.
[0043] Reference throughout this specification to “an embodiment”, “another embodiment”, “an implementation”, “another implementation” or similar language means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of the phrase “in an embodiment”, “in another embodiment”, “in one implementation”, “in another implementation”, and similar language throughout this specification may, but do not necessarily, all refer to the same embodiment.
[0044] The terms “comprises”, “comprising”, or any other variations thereof, are intended to cover a non-exclusive inclusion, such that a process or method that comprises a list of steps does not include only those steps but may include other steps not expressly listed or inherent to such process or method. Similarly, one or more devices or sub-systems or elements or structures proceeded by “comprises... a” does not, without more constraints, preclude the existence of other devices or other sub-systems or other elements or other structures or additional devices or additional sub-systems or additional elements or additional structures.
[0045] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs. The apparatus, system, and examples provided herein are illustrative only and not intended to be limiting.
[0046] The terms “a” and “an” herein do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
[0047] Embodiments of the disclosure will be described below in detail with reference to the accompanying drawings.
[0048] Figure 1 provides a schematic diagram of a Battery in accordance with an embodiment. The essential components of a battery (100) comprise electrodes, electrolyte (105), separator (104), and current collectors (101), as shown in Figure 1. The electrodes include cathode (103) and anode (102), typically made of different materials, such as lithium-ion, lead-acid, or nickel-cadmium, depending on the battery chemistry. They facilitate the transfer of ions during the charging and discharging processes. The electrolyte (105) serves as a medium for the transport of ions between the electrodes. The electrolyte (105) can be liquid, gel, or solid, depending on the battery type. The separator (104) prevents direct contact between the cathode (103) and anode (102) while allowing the passage of ions. The current collectors (101) are conductive materials that collect the flow of electrons from the electrodes to the external circuit.
[0049] Figure 2 provides a schematic diagram of the Battery Management System (BMS) (200) in operative communication with a cell (201) of the battery. The BMS (200) consists of two main components: a data acquisition database (202) and an embedded processor (203). These components work together to gather and analyze battery information, as well as generate control instructions for the individual cells (201) of the battery. The data acquisition database (202) plays a crucial role in collecting relevant battery data. It retrieves information such as the voltage, current, and temperature of each cell (201) within the battery. This data acquisition database runs a process, via a complier or processor, to ensure that real-time and accurate measurements are obtained and monitored comprehensively, and the battery’s performance is analyzed.
[0050] Once the above battery information is acquired, the same is forwarded to the embedded processor (203). The embedded processor (203) acts as the brain of the BMS (200), responsible for processing and analyzing the collected battery data. By employing advanced algorithms and control strategies, the embedded processor (203) examines the battery information in-depth and generates control instructions tailored to the specific needs of each cell (201).
[0051] These control instruction(s) serve to regulate and optimize the operation of the battery cells. For example, if the analysis reveals a cell with an excessively high voltage, the control instruction may involve reducing the charging current to prevent overcharging. Similarly, if a cell exhibits an abnormal temperature, the control instruction may trigger actions to mitigate overheating and maintain safe operating conditions. The embedded processor (203) ensures that the control instructions are accurately generated based on the analyzed battery information. Its intelligent decision-making capabilities enable it to adapt to various battery conditions and optimize the charging process for enhanced performance and longevity.
[0052] The present disclosure introduces a novel method and device for cell equalization and/or balancing during charging of a battery, utilizing a relaxation-based charging technique. This approach incorporates the concepts of relaxation time and boost voltage to carry out the cell equalization process effectively.
[0053] In this method, the relaxation time refers to the period during which the battery is neither connected for charging nor connected to a load for discharging. This dedicated period allows the cells to stabilize and provides an opportunity for the equalization process to take place. By incorporating this relaxation time, the proposed technique ensures that each cell within the battery pack has the chance to balance its charge level.
[0054] Additionally, the boost voltage is a voltage determined based on the monitored cell voltages. This boost voltage is applied to the cells to assist in equalization. By providing an optimal boost voltage based on the overall needs of the cells, the proposed technique facilitates the balancing of cells without the requirement of complex hardware or software.
[0055] The relaxation-based charging technique offers several advantages over traditional cell equalization methods. Firstly, the same eliminates the need for complex active balancing mechanisms or external circuitry, simplifying the implementation process, and reducing overall costs. This simplification streamlines the cell equalization process, making it more accessible and efficient.
[0056] Secondly, by leveraging the concept of relaxation time, the technique allows cells to stabilize and reduces the risk of overcharging or deep discharging. This reduction in the extremes of charging and discharging helps extend the battery’s lifespan and improves its overall performance.
[0057] In an embodiment, the device for cell equalization can be integrated into a battery charger, further enhancing the monitoring and management capabilities of the overall system.
[0058] In another embodiment, the sensors are installed at each cell of the battery to enable comprehensive monitoring and management. These sensors include a voltage sensor, current sensor, temperature sensor, balancing sensor, pressure sensor, humidity sensor, State of Charge (SOC) estimation sensor, State of Health (SOH) estimation sensor, gas sensor, buzzer sensor, and fan sensor.
[0059] The voltage sensor measures the voltage of individual battery cells or modules, providing crucial information about their state of charge (SOC) and state of health (SOH). This data helps assess the battery’s overall performance and condition. The current sensor monitors the flow of current in and out of the battery, allowing for accurate tracking of the charging and discharging processes. By measuring the current, the sensor can calculate the battery’s state of charge and provide real-time information.
[0060] Temperature sensors monitor the temperature of the battery cells or modules. This ensures that the battery operates within safe temperature limits, preventing overheating and potential damage. Balancing sensors detect voltage imbalances between battery cells or modules and initiate the balancing function. This function equalizes the charge among cells, improving overall battery performance and extending its lifespan.
[0061] In certain battery types, such as lithium-ion batteries, pressure sensors are used to monitor changes in pressure within the battery enclosure. This helps detect safety issues like gas buildup or leakage, allowing for timely preventive measures. Humidity sensors monitor the moisture level within the battery pack and identify any moisture-related issues.
[0062] State of Charge (SOC) estimation sensors utilize advanced algorithms and mathematical models to estimate the battery’s state of charge based on voltage, current, temperature, and other parameters. These sensors provide accurate SOC readings, allowing users to gauge the battery’s available capacity. Similarly, State of Health (SOH) estimation sensors use algorithms and models to estimate the battery’s overall health and degradation level, providing valuable insights into its condition and capacity.
[0063] In specific battery chemistries like lead-acid batteries, gas sensors are employed to detect the release of hydrogen gas during charging or discharging. This feature helps monitor battery operation and prevent potentially dangerous gas buildup. Additionally, buzzer sensors and fan sensors provide audible alerts or cooling mechanisms in response to specific battery conditions or events.
[0064] In another embodiment, the device comprises a data acquisition module or sensor data acquisition module responsible for retrieving the data from the individual sensors and processing it for further analysis or integration. The Data Acquisition Module may include circuitry, analog-to-digital converters (ADCs), and communication interfaces to facilitate the collection, conversion, and transmission of the sensor data or other relevant components.
[0065] Moreover, the proposed method and device can be seamlessly integrated with a battery management system (BMS) using communication technologies such as Universal Asynchronous Receiver-Transmitter (UART). This integration enables efficient control and monitoring of the boost voltage reduction and subsequent charging cycles, enhancing the overall management of the battery system. By integrating with the BMS, the method offers enhanced control and optimization of the cell equalization process, further improving the performance and lifespan of the battery system.
[0066] In one embodiment, the proposed method is performed by the BMS i.e., the BMS incorporates the functionality of the method within its operations. This integration allows for comprehensive battery management and control, ensuring effective cell equalization and optimal performance.
[0067] In another embodiment, the BMS comprises the device i.e., the device, which includes the control circuit, relaxation period control mechanism, and other components discussed earlier, is an integral part of the BMS. The device’s functionalities are incorporated into the BMS architecture, allowing for seamless coordination and control of the cell equalization process.
[0068] Figure 3 illustrates a flowchart outlining the cell equalization/ balancing method in accordance with an embodiment of the disclosure. The cell equalization method begins during the charging of the battery, where a control circuit continuously monitors the voltages of each cell within the battery, as illustrated by step 301.
[0069] The battery is set up for charging, incorporating a control circuit within a battery. As the battery charges, a control circuit actively monitors the voltages of each individual cell within the battery. This continuous monitoring allows for real-time assessment of the cell voltages and enables the control circuit to make necessary adjustments.
[0070] Based on the monitored cell voltages, the control circuit sets an adjustable boost voltage. This boost voltage acts as the reference voltage for the charging process, as illustrated in step 302. It is a voltage level determined by the control circuit to facilitate optimal charging and equalization of the cells. Taking into account the varying voltage levels of the individual cells, the control circuit ensures that each cell receives the appropriate charging level. By setting the boost voltage, the control circuit establishes a standardized reference point that guides the charging process and helps achieve balanced voltages among the cells.
[0071] In one embodiment, the charging setup of the battery can involve a charging controller or charger that incorporates the control circuit responsible for voltage monitoring and boost voltage adjustment. Alternatively, in another embodiment, the control circuit itself is integrated into the battery system.
[0072] The control circuit can be implemented using a microcontroller or specialized electronic components designed for this purpose. It continuously reads the voltage levels of each cell through sensors or direct connections to the cell terminals, ensuring accurate monitoring of the cell voltages.
[0073] The adjustable boost voltage is set by the control circuit through algorithms or programmed logic, taking into account the monitored cell voltages. This dynamic adjustment of the boost voltage allows it to match the specific needs of the cells during the charging process. By adapting the boost voltage, the control circuit ensures that cells with higher or lower voltages receive appropriate charging levels, promoting equalization among the cells.
[0074] The significance of the reference voltage lies in its role as a benchmark for the charging process. By setting a standardized boost voltage based on the monitored cell voltages, the control circuit provides a consistent reference point for all cells. This ensures that each cell receives the necessary charging level to achieve balanced voltages and minimizes any disparities among the cells. The reference voltage acts as a guiding factor in the charging process and facilitates effective cell equalization, ultimately enhancing the overall performance, lifespan, and safety of the battery.
[0075] During the monitoring process, the control circuit keeps a watch on the voltages of each cell within the battery. If imbalances are detected, indicating differences in capacity or resistance among the cells, immediate action is taken. The control circuit responds by reducing the boost voltage by a predetermined value, as illustrated in step 303. This reduction is aimed at mitigating the imbalances and promoting equalization among the cells. By adjusting the boost voltage, the control circuit ensures that each cell receives an appropriate charging level, facilitating balanced voltages within the battery. Imbalances can occur due to various factors, such as variations in cell manufacturing, aging effects, or inconsistent usage patterns.
[0076] With the boost voltage reduced, the battery is charged up to the newly established lower boost voltage under the control of the circuit, as illustrated in step 304. The control circuit takes charge of regulating the charging current throughout the process. This active regulation of the charging current is crucial to ensure safe and efficient charging of the battery. By carefully controlling the charging current, the control circuit prevents the battery from being overcharged or deeply discharged.
[0077] Once the charging process is completed, a dedicated relaxation period is provided for the battery cells, as illustrated in step 305. This period allows the cells to stabilize and settle after undergoing the charging cycle. Typically lasting between 30 to 60 minutes, the relaxation period offers an opportunity for the cell voltages to further equalize. During this time, any remaining imbalances among the cells tend to diminish. To implement the relaxation period effectively, the device incorporates a relaxation period control mechanism that governs the charging circuitry. This control mechanism ensures that the cells have sufficient time to stabilize and allows for the balancing of voltages, minimizing any disparities that may exist. The inclusion of the relaxation period further enhances the effectiveness of the cell equalization method, promoting a harmonious voltage distribution within the battery and improving its overall performance and reliability.
[0078] After the relaxation period, the method checks the equalization of cell voltages to ensure its effectiveness, as illustrated in step 306. If imbalances persist, indicating that certain cells require further equalization, the control circuit makes further adjustments. It reduces the boost voltage to a reduced level in subsequent charging cycles, ensuring ongoing cell equalization. This iterative approach prevents the accumulation of voltage imbalances over time, maintaining balanced cell voltages and improving the overall performance and lifespan of the battery, as illustrated in step 307.
[0079] In various embodiments of the method and device, a microcontroller or dedicated control circuit is utilized for monitoring and adjusting the boost voltage. The device may also feature a communication interface, such as Universal Asynchronous Receiver-Transmitter (UART), facilitating integration with a battery management system (BMS) for comprehensive battery control and management. Safety features like overvoltage protection, undervoltage protection, and short circuit detection can be incorporated to ensure the reliable and secure operation of the battery system. A user interface provides real-time monitoring of the cell voltages, boost voltage, and charging status for easy observation and assessment. Additionally, the method optimizes the charging current based on the battery's state and conditions, ensuring energy-efficient charging while maintaining cell equalization.
[0080] To enhance safety and optimize the charging process, the device includes temperature sensors positioned around the battery cells. These sensors provide real-time temperature measurements of each cell. An integrated temperature sensing mechanism adjusts the boost voltage based on the sensed cell temperature. If the temperature of the cells increases, indicating potential heat generation or thermal imbalance, the boost voltage is decreased to mitigate the risk of overheating and ensure safe charging.
[0081] Furthermore, the device incorporates a module responsible for controlling the boost voltage setting, relaxation period, and subsequent boost voltage reduction based on the individual cell voltages. This module enhances the flexibility and adaptability of the device, allowing for customization based on specific battery characteristics and requirements.
[0082] The present disclosure provides a highly efficient and reliable method for cell equalization during battery charging, along with a sophisticated device that ensures optimal battery performance, safety, and longevity. This embodiment represents a significant advancement in battery management technology, offering an effective solution to address voltage imbalances within battery packs.
[0083] To enhance safety and optimize the charging process, temperature sensors are strategically placed around the battery cells. These sensors continuously monitor the temperature of each cell, providing crucial information to the device’s temperature sensing mechanism. Based on the sensed cell temperature, the mechanism dynamically adjusts the boost voltage. If any cell temperature increases beyond acceptable limits, the boost voltage is decreased, preventing overheating and ensuring safe charging.
[0084] The device employed consists of a control circuit and a relaxation period control mechanism. The control circuit is responsible for monitoring the voltages of each cell, setting the boost voltage, adjusting it in response to imbalances, and controlling the overall charging process. It ensures precise control and coordination throughout the cell equalization process.
[0085] The relaxation period control mechanism is an integral part of the device, providing a dedicated control mechanism for managing the relaxation period. This mechanism allows for a specific duration of relaxation, typically between 30 to 60 minutes, during which the battery cells undergo further equalization and stabilization. It ensures that the cells are given sufficient time to reach an equilibrium state, minimizing any remaining imbalances.
[0086] The embodiment of the present disclosure offers a comprehensive solution for cell equalization during battery charging. By incorporating advanced monitoring, control, and relaxation techniques, this embodiment ensures optimal battery performance, safety, and longevity. The method and device work in perfect synergy, providing a reliable and efficient approach to manage voltage imbalances within battery packs. With its innovative features and intelligent control mechanisms, the embodiment represents a significant breakthrough in battery management systems, enabling the widespread adoption and utilization of batteries across various industries.
[0087] In one embodiment, the battery management system (BMS) incorporates a cloud-based central server, establishing a seamless connection between the BMS and a wireless display device. This wireless display device serves as an interface for users to conveniently access and monitor battery-related information. At regular intervals, the display device transmits all the displayed information to the cloud-based central server, enabling remote monitoring and management of the battery system.
[0088] The integration of the cloud-based central server adds significant value to the battery management system. By leveraging cloud technology, users can access real-time data and analytics regarding the battery's performance, state of charge, and health from any location. The server acts as a centralized repository for all the battery-related information, allowing for comprehensive analysis and monitoring.
[0089] In another embodiment, the battery management system (BMS) incorporates a charger and an IoT (Internet of Things) device. These devices are directly connected to the BMS, forming an integrated system that facilitates efficient charging and monitoring of a lithium-ion battery. The charger, under the control of the BMS, ensures optimal charging parameters are applied to the battery, preventing overcharging or undercharging, and maximizing its lifespan and performance. The IoT device enables seamless communication and data exchange between the BMS and other connected devices or systems, further enhancing the overall functionality and efficiency of the battery management system.
[0090] Furthermore, the cloud-based central server plays a crucial role in warranty validation for the battery bank and loads. By regularly updating and synchronizing the data pertaining to the battery bank and loads on the central server, the user can easily access warranty information. This feature provides users with a convenient and reliable means to validate the warranty status of the batteries and associated loads. The cloud-based storage and retrieval of warranty information ensure accuracy and transparency in warranty management, streamlining the process for both users and service providers.
[0091] Figure 4 provides a detailed block diagram of the device (400) used for cell equalization or balancing, illustrating the key functional modules and their relationships within the system. The device (400) consists of several essential components, including a control circuit (401), a relaxation period control mechanism (402), a comparison mechanism (403), a charging control mechanism (404), and a control module (405).
[0092] The control circuit (401) monitors the voltages of each cell within the battery and sets an adjustable boost voltage based on the monitored cell voltages. If imbalances in cell voltages are detected, the control circuit (401) takes action by reducing the boost voltage by a predetermined value. Additionally, it charges the battery up to the reduced boost voltage, ensuring that each cell receives an appropriate charging level.
[0093] After the charging process, the relaxation period control mechanism (402) comes into play. It is responsible for providing a relaxation period for the battery cells. This period allows the cells to stabilize and settle after the charging cycle, promoting further equalization among the cells.
[0094] To check the equalization of cell voltages after the relaxation period, the comparison mechanism (403) is employed. This mechanism ensures that the cell voltages are balanced and within an acceptable range.
[0095] Further, the control circuit (401) is designed to adjust the boost voltage to a reduced level in the subsequent charging cycle based on the determined imbalance in the cell voltages during the cell equalization process. This iterative approach prevents the accumulation of voltage imbalances over time, promoting balanced cell voltages.
[0096] The charging control mechanism (404) plays a vital role in reducing the boost voltage during subsequent charging cycles. The same adjusts the boost voltage based on the determined imbalance in the cell voltages, ensuring ongoing cell equalization and maintaining balanced voltages within the battery.
[0097] The control module (405) acts as a central controller, coordinating the boost voltage setting, relaxation period, and subsequent boost voltage reduction based on the individual cell voltages. The same enhances the flexibility and adaptability of the device, allowing for customization based on specific battery characteristics and requirements.
[0098] To optimize the charging process and enhance safety, temperature sensors are installed around the battery cells. These sensors continuously monitor the temperature of each cell. A temperature sensing mechanism integrated into the device adjusts the boost voltage based on the sensed cell temperature. This feature prevents overheating and ensures safe charging.
[0099] The communication between the control circuit (401) and the battery management system (BMS) is facilitated by Universal Asynchronous Receiver-Transmitter (UART) or other suitable communication technologies. This communication allows for coordinated control and monitoring of the boost voltage reduction and subsequent charging cycles, enhancing the overall battery management capabilities.
[0100] Overall, these embodiments enhance the functionality and usability of the battery management system. The integration of a cloud-based central server, wireless display device, charger, IoT device, and the direct connection to a lithium-ion battery result in a comprehensive and intelligent system. This system enables remote monitoring, efficient charging, and warranty validation, empowering users with valuable insights and control over their battery systems.
[0101] The method and device disclosed herein present notable advantages compared to existing cell equalization techniques. Through the utilization of a relaxation-based charging technique, the disclosure achieves effective cell equalization during battery charging without the need for complex active balancing or external circuitry. This simplifies implementation and reduces costs associated with additional components.
[0102] One of the significant benefits of this disclosure is its ability to ensure balanced cell voltages, leading to enhanced overall battery performance and an extended lifespan. The incorporation of a relaxation period allows cells to stabilize, mitigating the risk of overcharging or deep discharging and promoting optimal battery health.
[0103] Furthermore, the device can seamlessly integrate with a battery management system (BMS) using communication technologies such as Universal Asynchronous Receiver-Transmitter (UART). This integration enables efficient control and monitoring of the boost voltage reduction and subsequent charging cycles, ensuring precise and reliable cell equalization.
[0104] Figure 5 illustrates a system (500) comprising a battery management system (200) in operative communication with a battery (100) having a device (400) for cell equalization as claimed above. The battery management system (200) may be connected with the battery (100) via an interface (501) over an IP network or data network.
[0105] Figure 6(a)-(b) illustrates a pictorial representation of the average imbalance in each cell’s voltages at a specific time during charging of the battery in accordance with an embodiment of the disclosure. At this specified time, the battery has completed 11 scan cycles and is operating in charging mode. The individual cell voltages are as follows: cell 1 is charged up to 3.658 volts, cell 2 is charged up to 3.669 volts, cell 3 is charged up to 3.666 volts, cell 4 is charged up to 3.667 volts, cell 5 is charged up to 3.668 volts, cell 6 is charged up to 3.665 volts, cell 7 is charged up to 3.662 volts, cell 8 is charged up to 3.668 volts, cell 9 is charged up to 3.665 volts, cell 10 is charged up to 3.67 volts, cell 11 is charged up to 3.668 volts, cell 12 is charged up to 3.67 volts, and cell 13 is charged up to 3.664 volts.
[0106] In Figure 6(b), the minimum voltage, maximum voltage, average voltage, and the cell voltage imbalance in millivolts (mV) are mentioned. Specifically, at the specified time, the battery has a minimum cell voltage of 3.658 volts, a maximum cell voltage of 3.670 volts, an average cell voltage of 3.666 volts, and a cell voltage imbalance of 12mV. Additionally, the battery bank has an overall voltage of 47.838 volts, a current flow of -10.02 A during the charging process, a power of -479.310, an energy of 5 Wh, and a charge of 52 Ah.
[0107] Figure 7 illustrates a graph of voltage vs. time for each cell in the battery in accordance with an embodiment of the disclosure. The relaxation period provided in this exemplary embodiment is from the time frame 9:42 to 10:13, which is approximately 31 minutes. Additionally, Table 1 represents the imbalance of the battery before and after the relaxation time.
Table 1
Battery ID Cycle
No Mode Date Start Time End Time Duratio-n Energy (Wh) Capacity/ Efficiency Imbala-nce before Relexat-ion Time (mV) Imbalan-ce after Relexati-on Time (mV)
bt 110523 1 CHAR-GING 11/05/23 10:00:14 09:29 09:30 00:00:18 0.00 0 67 66
bt 110523 1 DISCHA-RGING 11/05/23 12:30:00 10:00 11:59 01:59:35 1297.00 90.07 403 256
bt 110523 2 CHAR-GING 11/05/23 17:08:11 12:30 16:38 04:08:02 1354.67 94.07 66 65
bt 110523 2 DISCHA-RGING 11/05/23 19:37:36 17:08 19:07 01:59:16 1295.00 89.93 399 295
bt 110523 3 CHAR-GING 12/05/23 00:22:25 19:37 23:52 04:14:36 1362.23 94.6 66 65
bt 110523 3 DISCHA-RGING 12/05/2302:51:53 00:22 02:21 01:59:19 1296.00 90 403 297
bt 110523 4 CHAR-GING 12/05/2307:50:56 02:51 07:20 04:28:53 1363.30 94.67 68 67
bt 110523 4 DISCHA-RGING 12/05/23 10:20:24 07:51 09:50 01:59:15 1295.00 89.93 403 296
bt 110523 5 CHAR-GING 12/05/23 15:00:38 10:20 14:30 04:10:04 1359.14 94.38 67 68
bt 110523 5 DISCHA-RGING 12/05/23 17:29:48 15:00 16:59 01:59:01 1293.00 89.79 412 308
bt 110523 6 CHAR-GING 12/05/23 22:05:54 17:29 21:35 04:05:55 1358.03 94.31 70 69
bt 110523 6 DISCHA-RGING 13/05/23 00:34:54 22:05 00:04 01:58:51 1291.00 89.65 415 314
bt 110523 7 CHAR-GING 13/05/23 05:25:48 00:34 04:55 04:20:40 1360.28 94.46 70 70
bt 110523 7 DISCHA-RGING 13/05/23 07:54:56 05:25 07:24 01:58:54 1292.00 89.72 412 311
bt 110523 8 CHAR-GING 13/05/23 12:58:46 07:54 12:28 04:33:37 1357.90 94.3 70 70
bt 110523 8 DISCHA-RGING 13/05/23 15:27:47 12:58 14:57 01:58:51 1291.00 89.65 403 301
[0108] The described method and device offer an efficient and cost-effective solution for cell equalization during battery charging, delivering improved performance, extended lifespan, and heightened safety for battery systems. This disclosure holds great potential for enhancing the overall efficiency and reliability of various battery applications.
[0109] The foregoing descriptions of exemplary embodiments of the present disclosure have been presented for purposes of illustration and description. They are not intended to be exhaustive or to limit the disclosure to the precise forms disclosed, and obviously many modifications and variations are possible in light of the above teaching. The exemplary embodiment was chosen and described in order to best explain the principles of the disclosure and its practical application, to thereby enable others skilled in the art to best utilize the disclosure and various embodiments with various modifications as are suited to the particular use contemplated. It is understood that various omissions, substitutions of equivalents are contemplated as circumstance may suggest or render expedient, but is intended to cover the application or implementation without departing from the spirit or scope of the claims of the present disclosure.
[0110] Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. However, the benefits, advantages, solutions to problems, and any component(s) that may cause any benefit, advantage, or solution to occur or become more pronounced are not to be construed as a critical, required, or essential feature or component of any or all the claims.
[0111] While specific language has been used to describe the disclosure, any limitations arising on account of the same are not intended. As would be apparent to a person in the art, various working modifications may be made to the apparatus in order to implement the inventive concept as taught herein.

, Claims:WE CLAIM:
1. A method for cell equalization during charging of a battery, comprising the steps of:
monitoring (301) voltages of each cell within the battery;
setting (302) an adjustable boost voltage for the battery based on the monitored cell voltages;
when the cell voltages are imbalanced, reducing (303) the boost voltage by a predetermined value;
charging (304) the battery up to the reduced boost voltage; and
providing (305) a relaxation period for the battery cells after the charging.

2. The method as claimed in claim 1, further comprising the steps of:
checking (306) equalization of cell voltages after the relaxation period; and
adjusting (307) the boost voltage to a reduced level in the subsequent charging cycle based on the determined imbalance in the cell voltages during the cell equalization.

3. The method as claimed in claim 1, wherein the relaxation period for the battery cells is between 30-60 minutes.

4. The method as claimed in claim 1, further comprising the steps of:
sensing temperature of each cell of the battery; and
adjusting the boost voltage based on the sensed temperature.

5. The method as claimed in claim 4, wherein adjusting the boost voltage based on the sensed temperature comprises:
decreasing the boost voltage when the temperature of the cells increases.

6. The method as claimed in claim 1, further comprising the step of:
performing inbuilt warranty calculation based on operation of the battery.

7. A device (400) for cell equalization using relaxation-based charging technique, comprising:
a control circuit (401) configured to:
monitor the voltages of each cell within a battery;
set an adjustable boost voltage for the battery based on the monitored cell voltages;
when the cell voltages are imbalanced, reduce the boost voltage by a predetermined value; and
charge the battery up to the reduced boost voltage; and
a relaxation period control mechanism (402) configured to provide a relaxation period for the battery cells after the charging.

8. The device (400) as claimed in Claim 7, further comprising a comparison mechanism (403) configured to check the equalization of the cell voltages after the relaxation period; and
the control circuit (401) further configured to adjust the boost voltage to a reduced level in the subsequent charging cycle based on the determined imbalance in the cell voltages during the cell equalization.

9. The device (400) as claimed in Claim 7, further comprising a charging control mechanism (404) configured to reduce the boost voltage in the subsequent charging cycle based on the determined imbalance in the cell voltages for cell equalization.

10. The device (400) as claimed in Claim 7, further comprising a control module (405) configured to control the boost voltage setting, relaxation period, and subsequent boost voltage reduction based on the individual cell voltages.

11. The device (401) as claimed in Claim 1, further comprising temperature sensors installed around the battery cells and a temperature sensing mechanism to adjust the boost voltage based on the sensed cell temperature.

12. The device (400) as claimed in Claim 1, wherein the boost voltage reduction and subsequent boost voltage reduction during charging cycles are controlled by communication between the control circuit (401) and a battery management system (BMS) using Universal Asynchronous Receiver-Transmitter (UART) or other suitable communication technologies.

13. A system (500) comprising:
a battery management system (200) in operative communication with a battery (100) having a device (400) for cell equalization as claimed in claim 7.