Lithium battery modules able to be serialized safely in unlimited numbers without the need for BMS, or any controlling communication

Abstract

This invention is based on the behavior of VRLA batteries, unlike current lithium batteries. VRLA fully charged batteries store thermal energy while other batteries are charging and gradually release it back into the environment. It involves creating a bypass path on lithium batteries to keep the voltage slightly higher after charging, reducing power loss and allowing safe serialization without the need for a BMS. Components like diodes and voltage limiters manage the charging and discharging processes to optimize battery performance. Thermal energy is stored and exchanged with the external environment to prevent overheating. During discharging, the bypass path ensures continuous discharge for other batteries in the series. Transistors and controllers regulate the flow of energy during charging and discharging to maintain stable performance. Overall, this invention improves the efficiency and safety of lithium batteries by managing heat buildup and optimizing energy storage and discharge processes without needing a BMS.

Description

Lithium Battery Modules Able to be Serialized Safely in Unlimited Numbers Without the Need for BMS, or any Controlling Communication

[0001] The generation and utilization of lithium cells and batteries are expanding quickly, but there are still impediments that cannot be a total substitute for other batteries, such as corrosive or nickel-cadmium batteries. One of these primary deterrents is that it is more often than not fundamental to extend the DC voltage in hardware such as UPS or sun-oriented vitality with powers of several kilowatts. For illustration, the foremost common UPS of six and ten kilowatts accessible within the current showcase needs 20 batteries of 12-volt arrangement proportionate to 240 volts. To reach these voltages, cells or lithium battery modules must be associated. To serialize them securely and in expansive numbers, utilizing the BMS battery management framework was vital sometime recently in the plan of this innovation. Both within the case of the serialization of lithium cells in a battery module and the case of the serialization of battery modules, but the claimed invention does its mission without the need for a battery management system.

[0002] H01M 10 / 0525

[0003] United States Patent 8624560

[0004] Controlling battery charging based on current, voltage and temperature

[0005] Some embodiments of the present invention provide a system that charges a lithium-ion battery. During operation, the system monitors: a current through the battery, a voltage of the battery, and a temperature of the battery. Next, the system uses the monitored current, voltage and temperature to control a charging process for the battery. In some embodiments, controlling the charging process involves: inferring electrode lithium surface concentrations for the battery from the monitored current, voltage and temperature; and applying the charging current and / or the charging voltage in a manner that maintains the inferred electrode lithium surface concentrations for the battery within set limits.

[0006] The mentioned method is a way to control and monitor the progress of battery charging while our claimed battery module works without battery management systems and serializes a group of batteries safely and unlimitedly since it has the features to transfer the heat cells and store the voltage.

[0007] United States Patent Application 20230261500

[0008] LITHIUM BATTERY CHARGE-LIMITING APPARATUS

[0009] A lithium battery charge-limiting apparatus includes a microcontroller, a current detector, and an electronic switch. The current detector detects a consumption current of an electronic apparatus having a lithium battery and informs the microcontroller of the consumption current, so that the microcontroller learns a plurality of the consumption currents. The microcontroller determines a first amount of a plurality of slopes of the consumption currents. If a second amount in the first amount of the slopes of the consumption currents are between a first minus number and zero, and if a next slope of the slopes of the second amount of the consumption currents is greater than a present slope of the slopes of the second amount of the consumption currents, the microcontroller turns off the electronic switch to stop transmitting a charging voltage to the electronic apparatus.

[0010] The mentioned patent’s focus is charge limiting which is only one of our claimed inventions; its main goal is to serialize the batteries unlimitedly.

[0011] United States Patent 9054396

[0012] Method for charging a lithium ion battery by increasing a charge limit voltage to compensate for internal battery voltage drop

[0013] The present invention provides a quick charge method belonging to the field of the battery and particularly relates to a quick charge method for lithium ion battery and polymer lithium ion battery. During a battery is being charged, the battery stops charging when the battery is charged to a charge limit voltage, and the charge limit voltage between two poles of the battery is set to be U=2U0−Us, and Us is a stabilized voltage which the voltage of the battery falls back to after the voltage of the battery is charged to U0 at a constant current, U0 is a standard charge cutoff voltage used by a low rate constant current-constant voltage charging mode which is normally accepted by the industries, and the stabilized voltage Us is selected as follows: timing begins when the battery stops charging at the constant current, and from a certain time segment, when the drop of an open-circuit voltage of the battery is less than a certain value within the certain time segment, which means that the voltage of the battery is stable, and a voltage corresponding to the first time point of this time segment is selected as the stabilized voltage Us of the battery.

[0014] The mentioned patent has similarities with ours but bold differences too, because it is a method and way to charge lithium-ion batteries, while our patent can be in a natural or organic way without a battery management system and it prevents unusual reduction of the cells.

[0015] A lithium battery module that can be serialized in a safe and unlimited number without needing a battery management system. Each module includes cells, switches for charging and discharging currents, voltage limiters, and reverse diodes. The module also features heat exchange components and an energy storage source to manage heat generated during charging and discharging. Additionally, it may include current and temperature sensors to regulate thermal losses.

[0016] As mentioned, the production and consumption of lithium cells and batteries are rapidly increasing and there are still obstacles preventing them from being a complete substitute for other batteries, such as acid or nickel-cadmium batteries. One main obstacle is the need to increase the DC voltage in equipment like UPS or solar energy systems with powers of several kilowatts. The most common UPS available in the current market requires 20 batteries of 12-volt series, equivalent to 240 volts. To reach these voltages, cells and / or lithium battery modules must be connected and serialized safely in large numbers using the BMS (battery management system). There is no problem with the BMS used inside a battery module because their protective power switches (for example, charge and discharge series switches) can be selected according to the total voltage of the cells inside. For example, for a 12.8-volt battery including 4 3.2-volt series cells, you can choose 20-volt batteries, or even for 12.8-volt batteries that are allowed to be connected to a maximum of 5 cells, you can use 80-volt batteries. This is because, since the lithium cells in a series do not fully discharge or fully charge at the same time, one of the internal power switches of the modules is opened earlier than the others, and therefore, almost all the voltage of the total cells of the battery modules is on that power switch. fall It is possible that the methods of creating synchronism between these power switches can make it possible to use lower voltage switches, but creating a new set of connections and controls greatly reduces the reliability factor and increases the price.

[0017] An increase in the nominal voltage of the power switches will cause them to become large and expensive, and if they are defective, it will also cause their impedance to increase in such a way that it makes it impossible to increase the number of cells in the series.Solution of Problem

[0018] The present invention is inspired by the behavior of batteries like VRLA when they are closed in series. Unlike current lithium batteries, when they are fully charged, these batteries do not cut off the current path and allow other batteries of the same series to continue charging until they are fully charged. At the end of charging all series batteries, their set voltage reaches a point where the charging current is almost cut off. VRLA batteries that are fully charged, while the rest of the batteries in the series are being charged, they store the thermal energy resulting from the product of the voltage on the battery and the current passing through it, and they heat a little, and after the charging of all the batteries is complete, it They gradually give back to the environment.

[0019] Usually, in all types of VRLA batteries, it is recommended that batteries of the same model series are from the same manufacturer and with the same manufacturing date. This is so that their tolerance is less than each other so that the heat energy that needs to be stored in the charged battery is minimized and the battery heats up less. For example, in a 240-volt DC UPS device, which contains 20 12-volt batteries in series, the minimum battery capacity is 8.5 amp hours the maximum capacity is 9 amp hours, and the recharge voltage of each cell is 2.45 volts when charging the first battery that Its charge is completed when it reaches the voltage of 2.45*6=14.7 volts, it is the same as the 8.5 ampere-hour battery. The voltage of this battery will remain around 15 volts during the time it takes to dissipate 0.5 ampere-hours of the difference with the most powerful battery. This means that the battery has stored a total of 7.5 watt hours equivalent to 27 kilojoules of thermal energy. If the sum of acid water, lead, and other accessories inside this battery has a heat capacity of 1800 joules per degree centigrade, it will be 15 degrees centigrade higher than the ambient temperature.

[0020] Therefore, to simulate the behavior of the VRLA battery in the lithium battery of the present invention, it is enough to create a bypass path on a normal lithium battery that keeps the voltage at both ends of the lithium battery slightly higher than its fully charged voltage after charging. For example, two battery heads containing 4 cells of 9 ampere-hour series of 3.2 volts with a nominal voltage of 12.8 volts and a full charge of 14.6 volts should be kept at 15 volts. In this case, it is enough to store 27,000 joules of thermal energy in this new bypass system. This energy storage can be a heat sink or a container containing PCM materials. (For example, in the example above, 150 grams of paraffin at 55 degrees Celsius). Where there is an expectation of maximum tolerance, the amount of thermal storage can be increased or at the same time, cooling can be done either naturally or by using a fan or other methods. It is also possible to reduce the power loss after full charging by turning off the power switch of the discharge path and reducing the voltage or bypassing both ends of the battery.

[0021] The bypass path on a normal lithium battery can contain a reverse diode in parallel, which, when the batteries are discharged, after the energy of the first battery cell is exhausted and by cutting off the power switch of the series discharge with its cells, on the one hand, it is possible to continue the discharge for other batteries in the series. On the other hand, it does not allow the reverse voltage to fall on a battery whose power switch is disconnected from its cells.

[0022] Serialization in a safe and unlimited number without the need for BMS:

[0023] A schematic of 4 battery modules 101, 102, 103, and 104 and their minimum internal components is shown in. There is no limit on the number of battery modules, and here as an example and to better clarify the explanation of the invention's performance, 4 battery modules are drawn. Inside each of these battery modules, there are one to several series and / or parallel sets of lithium battery cells 11, 12, 13, and 14. Each of these lithium battery cells and / or cells is serialized with one or more series and / or parallel keys 21, 22, 23, and 24. These keys can be electromechanical or electronic. Also, it may consist of two keys, one for the charging path and the other for the discharging path, like most of the current lithium batteries in the market. These keys are opened when the cells of a battery module reach the end of their energy at the time of discharge so that their voltage does not fall below the minimum voltage allowed for the discharge of the cells. Also, it is possible that one or more sets of internal cells of the battery module have reached full charge during charging, but the entire battery module has not yet reached its full charge voltage.

[0024] A diode 31, 32, 33, and 34 is located parallel to the + and - poles of the battery modules, which allows the discharge of the cells of the other battery modules 101, 102, 103, and 104 when the key or keys 21, 22, 23 and 24 are open. accept Also, there is a voltage limiter 41, 42, 43, and 44 parallel to the + and - poles of the battery modules, whose voltage is slightly higher than the full charge voltage of the cell and / or cells 11, 12, 13, 14 of the battery module. As soon as the voltage of the + and - poles reaches this voltage during charging, this voltage limiter will allow the charging current to be fully charged so that the rest of the battery modules can be fully charged. The thermal losses created in this voltage limiter, which may contain a large amount of energy in a short time, are stored in the thermal storage 51, 52, 53, and 54, and gradually during the operation of the voltage limiter and also after the end of their activity. It is exchanged with the external environment of the battery module. The maximum charging voltage of the set of battery modules 101, 102, 103, and 104 is usually set to the sum of the limiting voltages 41, 42, 43, and 44, so when all the battery modules reach these voltages, they are fully charged. The voltage will reach zero and their heat loss will stop.

[0025] The current paths in modules 101, 102, 103, and 104 are shown in their charging state. In this case, all keys 21, 22, 23, and 24 are closed and all cells and / or cells 11, 12, 13, 14 are charging.

[0026] During charging, the battery modules 101, 103, and 104 are charging, but the charging of module 102 or one of the 12 cells, if it consists of several cells in a series, is complete. In this case, in the interval when the rest of the charging modules are fully charged, the charging current passes through the voltage-limiting path 42. As a result of the current passing through the voltage limiter 42, thermal energy 62 is created. A part of this thermal energy is stored in the thermal storage 52. At the same time, another part of it, which depends on the thermal resistance between the thermal storage and the external environment of the battery module 102, is transferred to the external environment of the battery module 102. After the charging process of other battery modules 101, 103, and 104, the charging current is stopped because the voltage of the battery module set has reached the maximum charging voltage.and

[0027] All the battery modules 101, 102, 103, and 104 are fully charged. The thermal energy previously stored in the thermal accumulators 51, 52, 53, and 54 is gradually discharged in exchange with the environment outside the battery modules.

[0028] Inthe set of battery modules 101, 102, 103, and 104 in discharge mode is shown. As can be seen, all keys 21, 22, 23, and 24 are closed and the flow direction is toward the load.

[0029] We have reached the end of discharging the battery module 102 or one of the 12 cells if it consists of several cells in a series. In this case, when the key 22 is opened, the discharge current path is made through the diode 32. And the total voltage decreases slightly more than the voltage of battery module 102. Depending on the minimum acceptable voltage of the load and the number of battery modules, after the internal cells of one or more battery modules are removed, the entire discharge current is stopped.

[0030] In schematic 8an example of battery module 200 is shown consisting of 4 series cells of 110, 111, 112, and 113.

[0031] In steady state and during discharge and before the energy of these battery cells is exhausted, thermal tanks 119 and 126 are empty. Transistor 119 is turned off and does not provide any heat energy to the heat reservoirs 125 and 126, whose body is connected to the body of this transistor, because the + and - voltage of the battery module 200 is lower than the upper limit of its charging voltage, and therefore no current flows through the zener 122. In this case, transistors 114 and 117 are on. During the discharge process and with the complete discharge of the first cell from the cells 110, 111, 112, and 113, controller 124 turns off the transistor 114, which is the discharge transistor. At this moment, the voltage of the two ends of the 200 battery module is reduced to the voltage of the two ends of the 118 diode, and if there are other battery modules connected in series with this 200 battery module, their discharge current will pass through the 118 diode. The thermal energy caused by the discharge current passing through this diode during the discharge period is directed out of the battery module 200 through the thermal reservoirs 125 and 126.

[0032] When the charger is turned on and the voltage of the + and - ends of the battery module 200 increases again, the controller 124 turns on the transistor 114 until the battery is charged.Advantage Effects of the Invention

[0033] • Improved safety of the lithium batteries

[0034] • Heat buildup management

[0035] • Energy storage optimization

[0036] • Keep charging after cutting off the power current

[0037] • Eco-friendly

[0038] • No need to use BMS

[0039] • Unlimited serialization

[0040] Shows a Shows a schematic of 4 battery modules.

[0041] Declares the current paths in modules 101, 102, 103, and 104 in their charging state.

[0042] andshow the charging of modules 101, 103, and 104 and completion of module 102.

[0043] Presents that all the battery modules are fully charged.

[0044] Displays the discharge mode of the battery modules.

[0045] Shows the end of the discharging of module 102.

[0046] is an example of module 200.

[0047] Shows a schematic of 4 battery modules 101, 102, 103, and 104 and their inner components. Numbers 11, 12, 13, and 14 show the series or parallel lithium batteries, numbers 21, 22, 23, and 24 refer to parallel keys, numbers 31, 32, 33, and 34 are diodes, numbers 41, 42, 43, 44 show the voltage limiters, and 51, 52, 53, and 54 are thermal storages.

[0048] Shows the current paths in modules 101, 102, 103, and 104 in their charging state which means all keys 21, 22, 23, and 24 are closed. All cells or cells 11, 12, 13, and 14 are charging and show the series of lithium batteries in the schematic, numbers 21, 22, 23, and 24 state the parallel keys, numbers 31, 32, 33, and 34 are diodes, numbers 41, 42, 43, 44 refer to the voltage limiters, and 51, 52, 53, and 54 store the thermal energy.

[0049] andshow that the battery modules 101, 103, and 104 are charging while the charging of module 102, or one of the 12 cells if it consists of several cells in a series, is complete. Like other schematics, cells 11, 12, 13, and 14 show the lithium batteries series, 21, 22, 23, and 24 point the parallel keys, numbers 31, 32, 33, and 34 show diodes, numbers 41, 42, 43, 44 are the voltage limiters, and 51, 52, 53, and 54 are thermal storages.

[0050] Presents that the battery modules 101, 102, 103, and 104 are fully charged, and the thermal energy previously stored in the thermal accumulators 51, 52, 53, and 54 is gradually being discharged in exchange with the environment outside the battery modules. In this figure, cells, voltage limiters, diodes, and storage are the same as in previous ones.

[0051] Displays the set of battery modules 101, 102, 103, and 104 in discharge mode, and all keys 21, 22, 23, and 24 are closed and the flow direction is toward the load.

[0052] Shows the end of discharging the battery module cell 102 or one of the 12 cells if it consists of several cells in a series of the battery.

[0053] is an example of a 200-battery module with 4 series cells 110, 111, 112, and 113. In this schematic, numbers 11, 110, 111, 112, and 113 are lithium battery cells, numbers 114, 117, 119, and 120 are transistors, 115, 116, 118, are diodes, and 122 stands the Zener diode, 121 and 123 refer to the resistors, number 124 is the controller and numbers 125, and 126 are the storages for the thermal energy.Examples

[0054] The batteries are connected to various equipment such as chargers and uninterruptible power supplies (UPS) to be charged. This allows them to supply output power in the event of an interruption to the input power. In the case of a UPS, the batteries supply power through the inverter, while with a charger, they supply power directly.

[0055] This invention is used in the industries of electric cars, oil, gas, petrochemicals, steel, and any other industry that works with electricity because whenever the electricity connection is interrupted in the control rooms, it provides electricity.

Claims

A lithium battery module that can be serialized in a safe and unlimited number without needing a battery management system.According to claim 1, in each of the battery modules, in addition to the cell or the series cells and the switch or the switches for disconnecting and connecting the charging and discharging currents of the cells, there is a voltage limiter on both ends of the battery module, which allows increasing the voltage on both ends of the module and it does not charge the module to the maximum allowed at the time of completing the operation.According to claim 2, during the completion of charging a cell from the battery module, the current is transferred from the charging path of the cells to the path of passing through this voltage limiter, and as a result, at the same time, it prevents the creation of overvoltage on the cells or the unauthorized increase of the voltage on The battery module prevents the charging of the cell series due to the disconnection of the key.According to claim 2, in each of the battery modules, in addition to the cell or series cells and the switch or the switches for disconnecting and connecting the charging and discharging currents of the cells and a voltage limiter of the battery module, there is a reverse diode on both ends of the battery module which During the complete discharge of a cell from the battery module and by cutting off the discharge path of the cells by the key or keys of their series in the module, it transfers the current from the discharge path of the cells to the path of passing through this reverse diode.According to claim 4, while making it possible to continue discharging other series modules with this module, if any, it prevents the unauthorized reduction of the cell voltage or the reversal of the voltage on the battery module and as a result its failure.According to claim 4, in addition to the heat exchange of the voltage limiter and reverse diode with the environment around the battery module in a natural or force-cold manner, there can be an energy storage source connected to them in the battery module, if due to high charging or discharging currents If the rapid exchange of heat with the environment of the module is not possible, it stores the generated losses and then gradually transfers it to the external environment of the battery module.According to claim 6, this heat energy storage source can contain PCM, organic heat storage, or other types of heat energy storage.According to claim 6, the battery module can include a current sensor or a temperature sensor, which, if the size of the thermal energy storage source or the heat transfer capacity of the battery module to the outside environment is not sufficient, at the time of full charging and the time of disconnection of the corresponding series key charging, when the voltage limiter on both ends of the battery module causes thermal losses, by reducing the voltage on both ends, it reduces the number of losses.

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